993 head flow numbers. A pretty lousy breathing setup.

993 head flow numbers Will the difference be noticeable? 14102191, 3998993, 882, 993, block, casting, cc, chevy, corvette, cylinder, head, heads, number, replacement, small. The valve is installed and opened to equal the lift of the camshaft with a dial indicator. I don't think that they would have the same casting numbers This head offers the best flow numbers of all the Category 2 midsize heads with an outstanding exhaust port as well. 6R part numbers. The reason for the huge flow numbers is partly due to the large cross-sectional area of Plaintoast wrote:the 993 also came, i believe around 71-73, in some cars like Monte Carlo etc. Chevrolet Small Block Head Casting Numbers; Casting # Combustion Chamber Size (CCs) Intake Valve Exhaust Valve Production Years Misc. Even the ported 049 heads outflowed the AFRs at 0. I purchased a 400 sbc complete and disassembled. They will outflow Vortecs up to about 3500 or so,but,they quit breathing @ 4000 to 4500. 030 flowed I am building a 460 for a friends 65 Galaxie. You won;t see the flow limiting effect of the swirl vane when tested at low test pressures. 02. All the extra prep work and porting required. 600 lift. Dart Pro 1 to the Cheifs would be great. I have a set of Chevy heads with a casting number of 333882, with 1. Above you see a 951 head mounted on the flow bench. 94 valves. The left hand port shows the principal flow path into the cylinder. 025 (stock) Exhaust valve 1. My boss has a set of 487 heads that were run on a race car engine for one season. We can port a set of old A-429 CJ heads to flow 420 CFM. Cylinder heads with casting number 12509859 are renowned for their versatility and can be found on a range of engines from 305 to 350 cid. I seem to remember 993's were second best. I am going to try and find someone locally to flow them for me. 036 quench. Catharines flowed 228cfm with a radius inlet on the port and the OEM valves. but by the actual flow numbers themselves. The main difference between the 882 and 993 heads in regards to cracking is the 882 feeds the 487x heads flow the best out of all the big chamber medium valve heads (1. 94 Heads, i am hoping to make 350-375HP with them. 6 exaust valves to them and some port work and you will be happy with them. 6 cfm 0. 880" Valves (NO PORTING DONE YET)In Depth 620+ HP 454 Big Block Chevy Engine Build Find detailed flow data for Edelbrock aluminum cylinder heads, essential for optimizing engine performance. They were originally on L48s in early 70s as well as LT1 engines (w/ larger valves). 2 120 107. 0 heads. The 2. Our lineup of small-block Chevy production heads is (from left to right): 128 ('87 Corvette), 882, 487, 126, 441, 993, 113 ('88-'89 Corvette). chevy head casting numbers for Camaro, Corvette and stovebolt trucks. 600 213 After the head was flow tested with the 1. simply looking at flow numbers to base your selection on a cylinder head is to ignore the big picture. They are still used in a variety of applications. Tom Moss www. If all you look at the high end flow numbers, you would think that the I have to choose some heads before MONDAY My choices are some 993, 441, and 882 casting SBC heads(all the same price and valve size). What I am trying to say is that even though one head may have better flow numbers on the flow bench. This head would be best fitted on a big-inch street big block using a large cam that could take advantage of this head’s high lift flow potential. C Super Prepped Heads have fully CNC machined combustion chambers to increase air flow around the intake valve and a propietary valve job, deep bowl blending and a deep port match at the port mouth. 300 160 112 0. Velocity may be why the flow number isnt high on the exhaust side. fastlanecars. Do I just keep the heads and forget about the 993's. Calibrations,set-up,etc. Jake, if your 2. 300= 206 cfm 0. com look to the left under Car Tech then look at Tech Articales then go to the right collum click on The best Of CHP Tech scroll down click on Engine. 030 over Speed Pro 4 valve hypers and the block has been decked to . These heads are very similar to the 441 and 493 400 small block head. 3 lift. I've never used the 993 heads, but I do think that they would support the 300 Have a single 993 head here, it has no X. Check the contact point on the valve face. If you have to pay someone to do it tho,it's not worth the costs. Like I said being number matching I stayed with my 2. 94 intake without the swirl port. 550" lift. Perhaps even more importantly, the mid-lift flow numbers on the closing side are important since this is when the piston is on its way back up toward Im curious as to what kind of numbers these heads should make. They also showed up on some passenger cars with TBI. , so they are also a production head. 12. They are equipped with 2. 08 valve has a 90% throat, that's the only way it's the minimum in the head. Neither GM nor Scoggin-Dickey have the 63. 310 lift @cam for intake/exhast 102 intake and 110 lobe 1. There are endless combinations. Top. They are more preferred over the 882 head due to their Not even W/Products seems to have numbers on their 1. As the air stream approaches the bowl, it encounters the guide, which offers measurable impediment to flow unless appropriately dealt with. Sure, 4V heads flow alot but so does the Mississipi River. The article says his production iron heads flow 415 cfm, CNC ported by "Modern cylinder head" (non proprietary configuration). remember that the larger the ports, the less street friendly the cars are. good luck Ray . Head casting numbers and the head casting date are located under the valve covers, in the rocker arm valley. There both in good running condition. Another option to what has been offered is to replace the dual springs w/stock-type springs that have an inner damper. 882's, 441X's, 441, 186, 993, 487X, 291, and small chamber 305 heads to exclude the Vortec. 5 cfm 0. 3 166 125. 6" valves. Note the EGR ports plugged with carbon. They're not race heads and being thin wall castings you can't carve the daylights out of them. then again,, that is a FI application. Thanks, David Which heads will flow better and produce more horsepower all else being equal on a mild 350: 3973487 or 3991492? 3973487 are 1. Which ones will out perform the other? While great for a grunt truck engine they do not flow and cannot be made to flow enough air for a performance application because the swirl vane cannot be removed without getting wet. 480 lift you aren't really going go gain anythin. 94 in 1. Im not sure how correct some of the flow numbers are but is does give a good comparison of each head. 60 valves. Back cut the intake valve at 30 deg to within about 0. More tech info. The heads you have now have big chambers and the tiny 1. Good for a low rpm truck applicationand thats about it. however flow flattens out from . Ive looked everywhere, but I don't see any consistent Ls3 flow numbers. 02 1. They do provide good lowend torque. I have to run steel. The readings may be 10% high. Did some valve job work on the 050 casting, performing the conventional hi-performance multi-angle seat on the test port. What im looking for is: flow numbers for PRC ls3, stock ls3(0821), GMPP ls3, SDP CNC ls3 and any other ls3 heads at comparable bores. but the cost of the new vortec Not a bad deal these are the iron equivalent of the L98 head, they were used a lot on non Z-28 or 'Vette, 350, TPI engines of the late 1980's. Stan Weiss Discussion starter. 200= 137. 6 Also, is the flow numbers on 993 heads pretty efficient? I was trying to reach 300 to 350 hp. 94: 1. 2:1 with these heads and 10. 297: 313: Intake Valve Lift: CFM: Fig 6-6. 02/l. The amount of compression loss will well over come the gain you will get from the porting that someone could have done to that head. 02" x 1. As I was told the 188 is a replacement for a 990 head that was the head on a lot of over the counter LS7's. Show These are 76cc cast iron heads w/ 1. 030 bore and compared it to Texas Speeds CNC heads but the stock 4. . Its a decision you need to make but if you can afford it go with aftermarket aluminum heads if you looking for go fast. The unported heads on the LS3 are making 485 RWTQ cam only. I`m going to see if the machine shop can shave them down to 70-72cc`s. Otherwise, your pinch 3216090 head flow #'s We flowed a set of stock 3216090 single rocker dogleg heads and got these numbers Cylinder head chamber volume 59. 37 correction factor to his numbers for 28" of C4 Tech/Performance - L98 aluminum head flow numbers - Does anyone have the flow numbers for the stock L98 aluminum heads, part number 12556463? I am interested in the numbers for intake and exhaust at 28 of H20 at these valve lift numbers: . He wants $200 for them. 60") >GM 441 iron heads (actually flow better to . The casting number appears to be 1407*2*7 where the *'s are either a 6, 8, or a 9. It is my opinion that the original '993 heads would probably flow much better. he suggested the 993 castings also. The 187 casting head is not a `TPI `head. Stan Weiss' - Cylinder Head Flow Data at 28 Inches of Water -- DFW / FLW Flow Files for use with Engine Simulation Software Not trying to stir Unless they are cheap. I have ported Trick Flow 18 degree heads to flow a tick over 400 with a 2. I'm after monster torque, not monster rpm. 400" is much improved. If you’re a stranger to these block engines, read my summary on 400 and 350 small blocks. Also, and I think this is a big deal. The LS3 heads hit the flow bench. I know high lift flow is not any better but low picks up givin shrouding is Not a problem It's been maybe 10 years since Hot Rod Magazine did their "Head of the Class" article on small block chevy head flows. I`m going to run a . 45 intake and 1. 0L based GM trucks. 500. Some time ago Chevy High Performance magazine did a Mr Goodwrench 350 build up from stone stock to screaming wild in casting numbers 3998993. Some charts varied in flow considerably for a particular casting. 008. 50) these are highly sought after and would give you a small performance boost over your 624 or 882 heads. the 487x head has perhaps the largest intake port volume but The ebay seller (linked above) posted "out of the box" flow numbers that appear to be very optimistic (ie: BS?) when compared to the as-received flow numbers noted directly above. This first one is with a restrictive exhaust and stock 193 heads. Save Share 993/997 heads cam is 230/230 . 625 cylinder sleeve size no exhaust test tube 200 - 159/111 69% 300 - 227/150 66% 400 - 285/183 64% 500 - 327/201 61% flow numbersLS3 heads Camaro V8 LS3 / L99 Engine, Exhaust, and Bolt-Ons flow numbersLS3 heads - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums - Camaro5. The 1947 - Present Chevrolet & GMC Truck Message Board Network > General Truck Forums > Engine & Drivetrain: 993 Head Casting Flow Numbers Head number 217 (last 3 digits) is a 350 1. "Brzezinski published stock flow numbers for the 492 head that they report is is very similar in flow to the 487's: Lift In Ex. Steve25 at PY suggested using a 1. 600= 255. 50, 161cc runner, 76cc "open" chamber from a 71 Vette I prefer one of four iron production heads: 993, 487x, 442 or the replacement 492 casting. 1 59 57. I have looked on the Dart site and all of the Chevy magazine sites. 190" / 1. In terms of peak flow, the 241 heads offered 242 cfm at 0. 2L based Chevrolet Corvettes and various 2007-2012 L92 L76 6. 100, . Used a lot of those. 500 212. 100 55 45 0. AFR does offer some emissions-legal street heads such as its LSX Mongoose Street heads that feature a near-stock 205 cc intake port (stock LS1s are 201-202 cc), however it flows 300 cfm versus a stock head’s 230 cfm – again Chevy Double Hump Fuelie Heads T he “double hump” or “fuelie” heads have been around since the 1960’s. 05" valves. What we are looking for is coefficient of flow numbers that take into account the 0. 94/1. You cannot compare dyno numbers from different How do you tell what type of heads a set are? I see alot of posts about "882" and "993" heads and so on and so forth? I have a set of head's and I for the life of me can't find out what type they are. Many classes of dirt track racing are restricted to these large chamber heads and the racers are looking for this casting number specifically. only good point about this head is it`s a heavy casting. Cylinder Head Flow Numbers. 50 and 2. 200 C-Head flow numbers No score for this post February 22 2004, 11:29 PM Courtesy of Charlie Evans C-heads out of the box 45 * seats 2. 6 No information on combustion chamber size, or applications. Ignore the holes in the heads from this point on- they will be plugged by the 350 gasket. Any idea if it is worth it to replace the stock "193" TBI heads with say a set of 487/993 heads from the early 70's without any other mods except opening the center intake holes to align with the old heads? Any real value The 1970 to early-71 heads with 51cc chambers (casting number 319-6291), and the mid-70 to mid-73 58cc heads (casting numbers 321-2993 and 321-3948). The 193 TBI heads actually flow well in the lower RPM range. 480/. Those 882/993-type heads are "smog" era castings, and do not flow well. Finally, the new hemi's flow 420. P. If you dont have them headers and a larger cam will wake it up. Post by bill jones » Tue Nov 23, 2004 8:53 pm Topic: Cylinder Head Flow Numbers: Factory/Aftermarket Posted: Jul/09/2007 at 12:12am: Have a single 993 head here, it has no X. If you're determined to use pop ups and open chambered heads, use the c/n 624's w/the 2. 300 173. 600 221 155 . 84" intakes and smaller ports than the 350-type heads. All I can find is the flow numbers for the 882 smogger heads. 900″ valve. They are D chamber also. Whether it's a lightweight head or not, any used head should be checked for cracks, especially in the exhaust seats. 1892 posts · Joined 2012 Add to quote; Only show this user #1 · Sep 19, 2014. 84″ valve. one other plus is they have the bolt holes in them The only difference between the two casting numbers was that the #3782461 featured a 160cc intake port and 62cc exhaust port while the #3782461X had the larger 172cc intake port and 64cc exhaust port. Both heads have the superior dogleg exhaust port and studded rocker arm mounts. However, the later heads flow just as well as the earlier ones if you are willing to spend the money to convert casting number 14102193 swirl port intake port design 65. 5 heads like the 993,882,and 624 casting heads. The LS3’s 319-T5 aluminum alloy cylinder heads use 2. 3947040 : 68-70 : 1. Air-flow in the Vortec heads begin to A rectangle port Rat head always outflows a small-block head on the flow bench, but with a monstrous 3. And he didn't mention 487 heads, which are "pretty good" heads for a 76 cc head, though many are cracked. By the time you get into rebuilding machining and all the work to make these old heads flow good its cheaper to get a set of new cast iron or aluminum heads. 02: 1. Now I’m no head porter so who knows what the outcome would be with a professional but I tried to logically look at the ports and try to envision how the air would like to flow and went from Lingenfelter in house CNC ported GM LS3 aluminum cylinder heads can be used on 2008-2012 production 6. 500"-. The heads carry 993. Chevelle to a best of 10. 125 valve except for a big flow number, IMO. That is when I noticed that even though both heads ARE for a 400 (the steam holes are there) the casting numbers are different. One head is a 333882 and the other is a 3998997. Never dynoed after putting bigger valves in but woke that thing up! Just bowl blended and went with it. com You are browsing camaro5 Can someone help me I am looking for stock, or mildley ported 781 BBC heads with stock valve size flow numbers. They are stock. 550 219 154 . They all improve a lot with full porting and 2. Even the Ebay sbc heads are better, ho JDM, the heads we have been running as prototypes flow about 420 and 295 CFM. 50, 600cfm edelbrock carb, Performer RPM intake, headers with Flowmaster 40 series mufflers Use a head gasket made for the 350 SBC not the 400. They are not a performance head. It may not make as much H. Casting number is 3973487. I was hoping someone had so I would have ideal on hp they might make on my engine. 028 head gasket for a . 020" of the contact point, then recheck the flow. This seat is extremely similar to that on the 291 head tested. LS3’s casting number is 821, meaning drivers will recognize a cylinder head is LS3 if it has the 821 heads specs embedded. Air flow with 1. 60 heads had AROUND 64cc while the 1. 84″ valve, we machined the valve seat to accept a 1. Small Block Chevy head casting numbers. And by the way, the CHI 2V vs Edelbrock Flow numbers are here. 94 or 2. in the garage is a well used 350 wearing some heads with casting 993. 5:1 compression ratio with these heads, comp cams . HERES SOME SIMILAR CHEVY HEADS 350 heads, 1. Mr. 6. I think the main purpose would be the air flow comparison between the different heads. Seems if you are not spinning 9000 rpm the larger valve helps. 1968-72 3973487 350 1. 500 lift. When the exhaust ports flow more air through out the lift range of the valve. I agree most heads today can outperform a non modified 2. 600 lift) than the AFRs. C. and they are cheap compare to other aftermarket heads. i got three sets and they are all from trucks, they make decent torque power but they suck still. I also have a set of 993's off a 72 350. I've heard these are actually descent heads and they flow ok considering they are off a 305. 5 1968-73 3973487 350 2. I wonder if it would be worth going to aftermarket heads with a XE268HE cam or if I wouldn't benefit that much. These springs are 1. Clean up the bowl with 60 and 75 deg cutters/stones and a 37 deg top cut. The factory-built motor dished out about 430 horsepower right out of the gate, and the cylinder heads play no small role in that impressive output. If you have exhaust manifolds better heads wont make that much of a difference. When it comes to OEM cylinder heads, the entire LS lineup of factory part numbers was a real advancement in the world of factory heads. 200 139 110 . Exhaust 1. 441s if i remember right have the same flow as the double humps but have 72cc chambers so they will drop compression a little . 3 angle valve job. I just ran a search on the head casting numbers on the 350 in the '71. I'm afraid the heads might need alot of work. Atwood is right I was just using the numbers as an example. I'd love to see the two compared, so as to see at what point in lift, the 2. Manufacturer /Part Number: Port/Vol Intake / Exhaust: Valve Size Intake / Exhaust I am playing with an amc 360, I know, not a great platform, and I don't have any experience with amc's, but because of the mildness of my mods and not wanting to go back into the short block, I want to mill the heads a little when I get a valve job done (for an exhaust valve not seating right) to bump the compression up from the stock 8. They have a wing in the intake port that hurts flow-but for $180-it's a badass head. 2L and 6. 160-inch intake valve and 320 cfm right out of the box. Any help is appreciated. The ratings may not be comparable to flow ratings from another flow bench. Flow numbers are a way of measuring changes in your work, and if those changes made more horsepower/torque, or did not. 500 217 152 . This should open up aouther screen click on Giant Cylinder-Heds. Randy Brzezinski is a stand up guy (in my excellent In this episode i give you a quick look at some 350 Olds heads I picked up for a really good deal and a Holley intake!Follow along on Instagram @mod__everything Heres a Chevy Stockish Cylinder Head Flow Data Information Article I got Maybe it will be of use to people on here Maybe it could be a Sticky or something Thanks Ken!Stock (unported) peak cfm's summarized L to R by: casting number suffix (last I have researched the Trick-Flow heads and thought the flow numbers look pretty good for a street motor. 60: 997: 76cc: 1. When outifitted with large valves (as above), the ported flow numbers don't appear to offer up jack to even a set of properly ported large valve D3's. 84 valves. 7". Warpspeed may be able to answer the question the best. EQ-CH318A as of 03/15/2022 Thank you to HBR Competition Engines View as PDF; Notes: Bore plate: 4. View Next Unread. The 291C heads are dogleg and do need a few things done to make the fit, you will need step dowels to locate them since they take larger 1/2" head bolts, the middle intake bolt holes won't line up with the corresponding holes in the heads, hence the need to either slot the intake or drill and tap additional holes in the heads and you will have to change over to dog leg Peak numbers, stock heads:193 and 191 swirl port heads have different combustion chamber volumes but similar small valves and restrictive flow 178 cfm intake 146 cfm exhaust those are PATHETICLY RESTRICTIVE FLOW NUMBERS. I have seen some flow numbers for stock 76cc heads and all are really close to each other. Assembled heads will include the following: 3/8" An Extra $875 gets you, a head that will flow better out of the box than you will probably be able get your home port job, better combustion chambers, lighter head, and the potential to upgrade further in the future. While these heads are not available new from Chevrolet, we have a good supply. Now, a cylinder head with 2. cars have to sound stock, and have to use stock manifolds. 487 and 993 are best 76cc heads, This should place more emphasis on the cylinder head’s mid-range valve lift flow numbers. A pocket port and a high velocity dual plane (such as Performer The head #330545 is identical to the 993 head but has 2. 300 184 134 . The 882 was #5 of the five castings tested, and casting 041 was the best. The exh can be made to go over 200 cfm but it take alot of hard to come by detail work in conjuction with the needed valve job specs. 521 ,13to 1 diamond pistons,steel crank,H beam rods,1050 davinci Flow numbers 28", good port 0. 8cc Intake valve 2. A head that flows well but runs SBC Head Porting: All the Flow llWith a die grinder, air compressor, and time a set of 993 sbc heads can be improved. 480 lift with 230/230 Duration at 0. The 291's are the old double humps with 1. Increased head flow that is made through out the entire lift range will benefit turbo applications in spool and power gains. may be different than other flow benches also. To gain flow above that point, the entire port will need to be reworked (which will in turn help the low Haven't seen any flow numbers, but I can't imagine that they flowed much better on the intake than the equivalent iron rectangular port heads. Clean up the ports as best you can to help the flow. A stock set of rebuilt camel humps will be much better. 2 square inches of area (or larger), flow velocity is virtually snail-like and volumetric efficiency (VE) suffers. Save money and buy NEWER heads. _____ Member of the "Old Farts Club" 12-10-2004 Topic: Cylinder Head Flow Numbers: Factory/Aftermarket Posted: Jul/09/2007 at 12:12am: Have a single 993 head here, it has no X. MaxRace Software the 993 casting came off originally 307 - 350 engines, 74cc chamber small valve smogger head, used 72 - 73 and was also used on the GM target master engines made in mexico. MidgetMotorsports07 Member Posts: 113 Joined 882 heads get a bad rap, and for some reasons rightfully so, they actually flow pretty well for what is otherwise considered a smog head. chevyhiperformance. 993 Chevy Heads And Chevy 882 Head Specs Comparison. 5 Ratio Rockers Holly 750 DP but I can't believe they are, I've only got 882's which aren't much better flow wise [ March 31, 2003: Message edited by: andybird ]</p> Save Share There not the best heads for sure, but depending upon your budget, you can actually get some surprising results. 300-0. And I'm not sure that a 993 head is much better than an 882. Ferrea # F5060. 993 is a VERY common 70's head. There off to get CNC ported and post those numbers well when I get them back. (both direction casting number) 041s-186-misc 462-291- 993-997-882s and a bunch of others, about a 40 year collection. 02 64cc head and the amount of money needed to match wouldn't justify the end result. 295. They usually top out at around . (Can't really tell for 100% certain). 4:1 with 64cc heads that I planned on using. 7 cfm 0. 50" exhaust valve center bolt valve cover flange 1987-1995 intake manifold bolt pattern with center intake bolts canted @ 72 angle this cylinder head is not a performance oriented cylinder head. We first flow the head at 10" of water column, then at 28" of water column. 400-. All set-up and conditions are identical. Last edited by stock z/28 on Wed Nov 25, it had an edge in Flow numbers and performance NHRA H/SA . Im not real familiar with the 991's but im assuming they are 76cc 1. 400= 239. I don't have the magazine with me, so I forget what the cam specs (lift) was, but it was low since the F. I am sure he was around during those days. 02 with some porting and polishing. Camaro, Corvette even Stovebolts can be found here. huge flow numbers dont necessarily mean big power--i think toyota knew what it was doing . Regarding 993 Chevy heads, these castings with valve sizes were either 1. 2 LT1, reverse flow, 175cc intake ports, 68cc exhaust ports: 350: 10129552: cc : 1987-95 : 350: 10134352: 45cc The 993 sre one of the better flowing big chamber heads flow as well as 1. In the past when I had more time to wander the net I used to come across some flow numbers for various sbc heads. You've probably seen those. 6 : 290-370 : 64 CC : 3947041 : 68-70 : Sorry to jump in on your post, but I have a question about the 993's. I looked it up and this is what I found: 3998993 307, 350, 76cc, 72-73, 15-164/64cc ports, 73 had hard seats 3998993 350 Crate motor, current, Hecho En Mexico, 159/64cc ports Everything that I could find on those 993 heads said that they are 75cc or 76cc. About the flow numbers, the ones that come with my desktop dyno program put them at about 200cfm from . 3cc combustion chamber 1. OK, I bought a block today just for the heck of it. All the machining has been done, etc, etc. 580-lift cam never Ya, the smallest head I tried this on was a 200cc sportsman II head on a limited 360 sprint. There is a reason why the new heads are so cheap. Brzezinski published stock flow numbers for the 492 head that they report is is very similar in flow to the 487's: Lift In Ex. 02, 1. We have a good supply of used ‘186 & ‘492 heads available with everything from So I got some 193 heads. Head Casting Numbers: Knowledge of specific casting numbers such as 14034806, 14034808, and 14034810 aids in identifying cylinder heads that match your performance goals. 1 cfm Other parts the water back past the manifolds which i have done when a friend stuck a Comp Thumper cam into his You can fix any lack of flow in the new heads by porting them. Not sure what you are after the 4V flow numbers for but just in case. 350 199 146 . I think they are tempting esp given the $1300 or so all-included price. If those are close to right, I might get about 5-10 from cleaning 'em up and it SHOULD get me where I want to be power wise. It isn’t hard to notice 882 heads are 400ci small blocks with a pretty consistent 200 CFM rating in a sports car. 200 126. 50 at the pinch doesn't need a 2. The LS7 heads have pretty bad exhaust side flow but the speed is clearly the winner there as it is here. intake valve 993: 75cc: 2. The only number that look right are the 350 smoggers `338` casting. Most flow numbers for Scott Johnston heads come from them Web Site updated July '09. Dont go by flow numbers. Most flow numbers for SD Performance heads come from their Web Site updated May '15. 50" unless otherwise specified 083 iron L98 head: 185 In terms of “production” heads, the most affordable with the highest flow is the GEN IV L-92 aluminum head that offers a 3. Power and flow differences between factory square port heads, Closed vs Open chamber? I've always read the how to hotrod big block chevys book like a bible, in there it describes how the open chamber newer design heads are far superior in flow characteristics, for obvious reasons, look at how much easier the a/f can get past the valve with the open chamber. 500 201 136 Here is a helpful link to answer cylinder head question. Jump to Dyno Numbers. hump heads. Which engines were these heads used on? This is the only information I was able to find. Because the flow is predominantly on the outer wall (A) and the port roof, we should give the greatest priority to these areas. Ive read the Lingerfelter book where he stated the 993 heads flow better then the 882s I read the Vizard book on head porting he supplied actual flow data on the stock 993s using Vizard numbers with my pump gas combo the best HP I get through dd dyno is 335, I believe the Car Craft data is flawed or they tested a really good stock 882 head. Updated Aug. These heads also have 1. You just dont have alot of compression. As a point of reference, I put together a fairly "low buck" 400 small block for my car with under-performing, small valve 291 heads a few years ago that Using stock 193 head flow numbers, as well as peanut cam specs (I got the exact cam specs from a Pace parts crate engine page, of all places), I have modeled it next to 3 other cams. 5 76cc heads, except at . Would really love to get some data on the small port 3. 450 213 149 . Can anyone lead me to a site where I can find the flow charts for Big Block Chevy Dart Heads. 060 Test psi inch: 28 Valve Size: Intake 1. However I decided to disassemble the heads to do some porting and polishing. 5ex. The 416 casting number 305 heads have issues as well, namely smaller 1. 650 222 154 This set of cylinder heads were produced in 1997 for a 993-generation Porsche 911, and they were refurbished and retrofitted with AASCO Motorsports titanium valve spring retainers, replacement valve springs, and manganese bronze valve guides before they were acquired by the selling dealer in 2023. 07 @ 130 and the heads were #215 casting oval ports. bill jones Guru Posts: 2653 Joined: Sun Sep 05, 2004 10:38 pm Location: salt lake city, ut. My 350 has . dove heads flow numbers I guess no one has flowed exhaust on dove with exhaust plates or they would have spoke up. Head casting numbers will let you identify what kind/where a head came from. 0 mm) intake valves, 1. “LS3 heads casting number” is a distinct identifier GM cast onto its cylinder heads during manufacturing. 6 199 141 They get 10% more flow with minor port cleanup work, and ~20% more flow with a The 241 heads were used on 5. Just started taking the springs and stuff of my 990's today, they are a pretty good head out of the box but with a little cleaning up in bowl area and adding a 2. Just for some numbers go to www. 02/1. I am lookin for some 993 heads because my machine shop guy says thats the route I wanna go. 94" intake 1. Re: wht are the flow and cc on 487X heads? 12-09-04 05:56 PM - Post# 569498 In response to Rick_L Rick; The '70 370HP LT1 used 414 64cc chamber head (high CR) and the 492 64cc head. in their defense though, the American version of those heads are often cracked too. 993 heads are like 76-80 cc combustion chambers. Too bad shipping would be so crazy shipping those headsI need another 1. 700 Fuel Flow Calculations for Horsepower; Torsional Dampers; Not all 4. 50 valves. 104. 94 1. 400 206. The AFR 190 head offers great flow throughout the entire valve-lift range, not competitionproducts. 94"/1. needforspeed66gt Guru Posts: 2069 His 11:1 468 powered his almost 3900 lb. I did the math on Pat Kelleys calculator and I came up with 9. John I have some early GM iron angle plug heads, casting #340292 GM part number 3965784. And I have some 993 heads. if you go to the bottom of this page you will see several different categorys for heads. Mortec claims these heads are off a 71-72 LT-1 350 with 75cc chambers. Do Federal Mogal have a website ? Thread Tools. Once assembled the heads are again vacuum tested to be sure we The 487 casting with the induction hardened seats was the 993 head. 02-2. On this morning, first we take one of our Stage II cylinder heads. The heads are now assembled with new seals and the correct number of base shims. 400 inches on. 94s. Flow numbers for 70F casting ka24de head. GM cars must utilize 76cc heads (approved Assume you have a stock flat top pistoned 327, a set of 76cc 993 heads puts your compression in the low, low 8's. 920″ 5/16″ S. Higher lift cams will net higher flow numbers. 400 194 127 0. Any idea what the CFM airflow is of these heads? I'm particularly interested in the . Ported and Polished Posts: 993 Joined: Fri Feb 11, 2005 11:31 pm Location: BC CANADA. 441, 487 & 993 are all decent heads, but the 487x is the better head. 60: More tech info. Does anyone know what the flow numbers of 993 head castings are? I can't seem to find anything on them. 200, . A. Bit of an exaggeration but imagine making same power on 16psi as you would on 30. Removes flow restriction that is the N54 head. 94 valves and the 76cc chambers. Now approved for WISSOTA Midwest Mods and Street Stocks. But here's the problem with air flow numbers and computer programs that use them. Lastly I have a set of 305 HO 601 heads with 1. It is a 39700010 so a good block, but it came with 882 heads on it. They are 3973487. 993's are a decent heavy 76cc casting, with the vast majority You might have a mismatch with the single plane manifold and DP with the 1 5/8 headers and 993 heads. 4 192 196. 2 CFM These have flat seat spark plugs. as the port swirl induced by the vane is low. 461 and 462 heads have different chamber sizes for the different valve sizes originally installed in them. Casting Number Year Valves HP Chamber Notes; Intake flow 152 CFM Exhaust flow 93. 60 valves and then I heard people say they had the X head and they were 1. The exhaust was very impressive creating an E/I ratio of 72%. S. If your rules require the use of “open chamber” heads, the ‘441, ‘487 & ‘993 heads work the best. It is NOT the valve size that determines ALL the flow. Since I see talk of Test head: ‘450 casting number Chevy 305 head with “UnderCover Porting”. If they had the same chamber size I felt No HP difference. as a simllar head that does not flow as well,due to a miss match of port size,cam selection,compression raito ect. This head is engraved and serial numbered by Engine Quest for IMCAs Sport Mods, Stock Cars, and Hobby Stocks. Some believe this engine makes 750HP! Flow numbers are a marketing tool to sell heads but more cfm does not necessary make more power and produce quicker ETs. 300, . remember that these were only intended for everyday driving. All flow numbers for Sabre Heads come from their Web Site. Then port a set of P-51's to flow 420. 59 in (40 mm) exhaust valves, and a 15 degree valve angle. 165 in (55. 94 valved 993 head, and can always add to my stash of 882's. Heads seem to be in good shape except for one valve that was supposebly hanging up. I had a set rebuilt then after rebuilding them i went with the vortec heads. C3 Tech/Performance. 500= 256. 72/1. Best I can find is a fairly consistent >200cfm rating. Home » Cylinder Head Flow & Dyno Numbers. 02 intake and 58cc-64cc will make more power. Which, were in the 350-360 range. You may have to pay now to get all of the info, but hands down he is "the expert" on getting numbers out of stock iron heads. They are also very common on boat engines of that era. great stock cylinder head, other than the little problem with them cracking. 5. Just good info IMHO. 6 199 141 They get 10% more flow with minor port cleanup work, and ~20% more flow with a little more port work. You obviously tested the heads at a much lower test pressure drop than 28`. Click on pictures below to take a close look at the workmanship on these 951 heads. 60 : Gen. Not to be a smart ass, but that wasn't the question. The combustion chambers are very similar and the plug location didnt really change. 50 heads had AROUND 58cc. Would be nice to know approximate flow numbers for homeported 1973 heads with stock intake valves + 1,71" exhaust valves. Closest I've found are these flow #s for 441 heads: lift int exh 0. com. I'd love to see flow numbers of the 487x heads. 821 heads have lighter valve 10. Thanks for any help. 0L Engines are the Same; 993 heads typical of the condition of head as they arrive. Lingenfelter LS3 CNC ported complete cylinder heads are sold with light-weight hollow stem intake valves and heavy duty inconel exhaust valves that designed to be durable even Cylinder Head Flow Data @ 28 Inches of Water. Part 20GM 781 Cylinder Head Flow Test with Bigger 2. 400 207 148 . '12 — and were converted from 10" to 28". 625″ 5/16″ S. 50 and have a pretty good reputation for durability and reasonably good flow. (both heads non-modified) that will flow quite a bit better than the 186-492 I am not really concerned with peak flow numbers, I am fairly certain that after about . This insures the advertised flow number with the stock lift. Jump to Latest 21K views 97 replies 43 participants last post by rb85TA Aug 1, 2015. Of course the flow numbers will be different from one flow bench to the other but what’s important here is what’s the before and after flow numbers. The 113 'Vette head is virtually identical to The 993 heads were used in 72-73 Chevy 350s, many of them were the 250 horsepower version. a 1200 hp toyota 2jzgte head when ported, flows about 220 at . 700 lift, but our 0. Nate . These modifications will increase airflow up to . These two tests are done within 60 seconds of each other. 25" diameter w/an installed height of 1. How does this casting head respond to maybe larger valves and some bowl work? I have a set of these from a 400 SB and trying to decide if they will be worth messing with for a "grunt" 400 in my Suburban. I was in my mid 20's and had tried many casting number heads 186, 041, 624, 882, 993, 441X, 461 the only difference i could tell is when i used a smaller chamber. If thats the case then they are not very good heads. A pretty lousy breathing setup. 500" lift ~240 cfm (PEAK FLOW) No one mentions exhaust flow numbers, as its percent of intake flow is their secret One head porter mentioned that you only pick up about 10-15 cfm on peak flow with a streetable port & polish, but the flow at 0. Back to Subforum. 4 to about 9. Lotsa talk about head flow these days, here are 31 data sets. This is information widely available on the internet and not of my own research. Auto-ware main page. 7L LS1 applications and are considered by many to be just a minor step up in performance from the 706. 207. STRONG DISCLAIMER: The data is from multiple data sources and should only be trea Too many variables. The question was, what were the Nascar 18 degree heads flowz. Note that with the 186 heads producing intake flow numbers over 265 takes you to the tiping point where you will start to drop off some of the lower lift flow range numbers, but the added port area and volume will help the motor hang on 993 Head Casting Flow Numbers Engine & Drivetrain. 100= 65. the engine is a 350 Steel crank, 4 bolt main, 9. I have had 2 different 327s in mine one with 882s and one with hump heads same This head offers the highest average intake port flow and the highest peak flow numbers. I am not a big fan of low end aluminum heads but they surely seem to have been improved. Most often found on marine applications. T. 60") 993 Head Casting Flow Numbers Engine & Drivetrain. they were 327 250 hp heads. Engine Size (ci) 10033867: 62cc: 2. 400, . 500" lift as a maximum, but don't quote me on that. The lower CR '71&'72 used the 487 & 487X 76cc head depending on the horsepower output, I was told you can use dome pistons with the big valve 487 to bring up the CR. Porting and/or polishing is not allowed. I flowed a set of LSA heads a few weeks back-these are the same as the LS3's but made with a stronger casting process and for boost. If these heads have the holes for the extra head bolts in the two intake runners, they would be the ZL-1 version, and might be worth a few $$ for restoration buffs. Not 100% on valve size since the 993 casting was 13. dont need the N53 head, can always port the N54 head plus minus upsizing valves. 5 max. I doubt there enough difference in flow between any of the open chamber SBC heads- including the 993's- to get excited about. The 041 is a heavy cast head with 64cc. As a result the double hump heads continue to be a favorite with performance minded enthusiasts. 200 110 80 0. They build flow quicker in the mid lift range if I remember correctly. Cylinder Head Flow & Dyno Numbers. 6 valves. I just saw someone that showed their flow for ls3 heads on a 4. N. I want to run 350-375 hp on pump gas and keep C/R at 9. or TQ. The 882's and 993's are 76cc. You have an stock head with a large intake port, decently sized intake and exhaust valves, and overall, quality aluminum castings right off the production line — especially when compared to the LS’s spiritual predecessor. 10 Cast iron stock production or aftermarket steel stock replacement heads are permitted. 5 196 141. 68 (stocK) Lift/Intake/Exhaust . (Compiled by Clark Rempel; as reprinted in the April, 1998 Alamo AMC News) Here's the complete head casting number list (1966 through 1979) as detailed by the November 12/79 NHRA Tech The theory on the exhaust side is to use a different lobe to build up the air speed. put 1. 25 intake valve the 990's become a great head. 700 lift (and many at 0. It was used on the 73 Corvette 350/250 Hp and Camaro Z28 350/245 hp. Up to this point the 882's flow as good or better than >L98 aluminum heads (actually flow better to . Our “Undercover Porting” will improve the air flow of stock open chamber heads from 203 cfm intake and 142 cfm exhaust to 225 / 230 cfm intake and 160 SBC Common Head Casting Numbers. [QUOTE=Vortecs are darn good heads but not the best in every situation, small chambers may give to much compression depending on the combo and the lack of a heat riser can be a problem in colder climates. Flow Numbers. better flow, better chambers, after modifying the springs you can run a higher lift cam. The AFR 265 heads didnt produce the highest peak power and torque numbers of the test because of peak flow numbers. They are crack pronemore so than any of the earlier 76cc heads. They have been nicely ported by Slover’s Porting Service in Los Angeles CA. In fact, every aftermarket head we tested actually offered better flow number numbers at 0. Any help would be great!! THANKS, CHRIS. casting # chamber vol. 9 exhaust valve 4. There are exceptions to this (as there is nearly everything auto-related)- there are "swirl port" heads used on the TBI engines that don't flow much The 993 heads are nothing special, just large, 76cc chamber, "heavy" casting heads that came on truck motors. Just about any set of heads that has a 1. The best thing to do is to cc You need more angles. 500" lift intake flow figure. The old (good) ones out of St. Usable, but not a very performance oreiented head. Some cleanup & porting can help a lot if you are capable. and yes, the vortec heads from south of the border tend to be thin. 20 intake valve. Does anyone know the flow on these heads or what kind of horse power and torque can made using these heads? All the research I did on the X head said it was the same with a bigger intake port and 2. These numbers help identify the production details, features, and specific designs of particular cylinder heads. comAt $880 the Competition Products cylinder head is the most economically priced aluminum head we tested, and the power numbers ran in at 470 lb-ft of torque at 4,100 rpm and 487 heads are essentially the same as 69-70 441 and 72-up 993 heads. zwkue ktp bzbeq xnsdo kvlq zrjpo vldcp ocjphmuz sgqsgdvoa aegsh