76cc heads with flat top pistons. 010" to basically leave the piston down .


76cc heads with flat top pistons. 04 flat top pistons-zero decked block-0.

With a 4cc dome, (the typical flat topped style dome that is about . 2 to 1. 0:1 with a 76cc head and . Nov 6, 2006 · Actually, the '68-'70 engines had 10:1 compression, which was then lowered in '71 to run on low octane gas. May 25, 2010 · I have some in the mid 240 @ . Feb 18, 2017 · The drop from 375hp from the 70 LT 1 to the 330 hp 71/72 LT1 was a drop in compression from 11:1 to 9:1 by changing from a domed piston and 64cc head to flat top and 76 cc head. 480 Stroke, 5. But with 76cc heads you will be fine with the flat tops ,i would work on getting your quench right by decking the block that will reduce your chance of detonation by aiding in turbulance for a more complete burn. Years ago, I ran a 406 with flat tops & 64cc heads. A shim gaskit will net you about 9:1 compression also not ideal. Keith Black, Hypereutectic Pistons, Chev 350, 4. OEM deck height is . 040 over, needs to honed and have a crank put in it. 450 lift hydraulic cam rule with 4 valve relief flat top pistons. Now all i need is Mar 23, 2008 · I went back with flat top pistons and the original heads. 042-inch-thick head gasket and a 76cc chamber, which is typical for a stock iron Jul 26, 2015 · The basic GMPP crate engine comes with dished pistons especially those with 76cc heads. It will be exciting, you may need to readjust the carb, definitely run higher octane fuel to reduce detonation. I get an intake closing point for your Lunati cam of 63* ABDC. Apr 11, 2010 · Let's say we use a Speed Pro H631CP30 piston that has a flat top and 5 cc's of valve relief. Mar 22, 2011 · Use Summit's compression ratio calculator. Assuming a . Just like others have said, if in doubt with your combo, use some clay and ensure that you aren't hitting piston tops with valves which usually happens when heads have extreme milling done, or block or both, or running a radical cam with screwy valve timing. They still used the 0. I have had problems with pinging at compression ratios lower than 8. 060 Bore, 3. 0 while the same engine with 76cc chamber heads will have a 8. 6 which sucks and hurts performance which also limits a great cam, so for a just cam swap with a heavier truck as the Elky is with not to much of a stall I would probably limit cam to a 268 hyd from Comp, have installed quite a few with about Aug 15, 2012 · Rebuilt 350, flat top pistons, 882 heads, street dominator intake, holley 650 carb, but i went with the comp thumper cams and a rebuilt 700r4 with alto red clutches. Mar 18, 2010 · - 10. 5cc and 7cc for different flat top 4vr pistons). 2 (64cc/Flat Top)BR Ringlands: 5/64, 5/64, 3/16BR Weight Piston/Pin: 535/145BR This is an all out Hypereutectic, T-6 heat treat piston with machining features of their next generation forgings. I can swap out to a flat top piston or small dome as long as I can keep piston weight the same so i dont have to rebalance. It will run on good pump gas at that if you are careful with the timing curve. Jun 5, 2020 · Good morning everyone, I just bought some sealed pro pistons, other than the over-boar they are identical To stock. Aug 1, 2008 · Combo A:Let's do a typical flat-top piston with four valve reliefs (roughly 6 cc for volume) along with a 0. 039 and you get 9. So if you have flat top pistons your compression would go from 9 to 10. Mar 13, 2009 · yeah, sorry for the long post. 7 to 1 Doves with 75cc 11. So the two engines can never be completely identical. Apr 23, 2020 · Hell, a zero decked flat top 383 with 64cc heads is over 11:1 compression. 030/2^2*3. 565") rods you are using. Jun 14, 2007 · Iron Heads I stayed with stock iron heads. 111CR. Part Number: 648 10. 0:1 with flat top pistons, and 9. I'm thinking of running a 302 SBC to help with better traction on dry slick tracks because of lower torque of the 302 SBC than the 350 SBC. 39 cid Aug 15, 2007 · Without going into a bunch of math, you're probably losing 1. That's using bore 4. 1971 heads all went to 76cc. 7 to 1 CJs with 72cc 12. Part Type: Pistons Model: Icon 2618 Forged Pistons Application: Chevrolet SB Gen I V8 Piston Style: Flat Top w/ 2 Valve Relief Cylinder Bore: 4. 39:1 with a flat top piston. ’70-’73 500). When I calculate your engine I get 10. Jul 25, 2014 · The fuel lights off in the head so that combustion chamber size and shape is very important . so i am leaning to the vortec heads. 540. The vortec heads have the best of everything for a factory head. 015" at TDC then compression ratio is 10. The heads were redesigned later to allow the use of the flat top piston instead of a huge bathtub. Speed Pro does not list approximate compression ratios that I can find. The engine will not run on regular gas! but it will run on middle grade gas. Dished pistons with 64cc chamber volume Heads Oct 31, 2020 · A zero decked block, flat top piston with 5cc valve relief and a common Fel-Pro composition gasket computs out to 11. Jul 26, 2020 · BigBro74 wrote: ↑ Sat Jul 25, 2020 5:08 pm Here is a related question- I am contemplating a build for my niece for a ump “factory stock” class car. Would like to use a . im hoping to have atleast a 9. 040" with a zero deck. Hope this helps. 1" dia head gasket and the piston top down . 060 over bore sizes exc. 25:1. 039 fel pro head gaskets, 76cc heads and the head gaskets blew so I opened up the motor (still in car just took off heads and intake) and saw that the motor is very fresh and was hardly used and it was a radiator problem that lead to the overhead and blowing of the gaskets so my question is about the pistons. 7:1. 88 Original price was: RB55172 10:1 Forged Pistons – 500 CID w/ 76cc Heads – D-Dish $ 750. Apr 4, 2002 · There's not much info on the web about these pistons, except that they are a good, forged piston, and have a . The best way to improve power on your small block Chevy would be to not attempt to save those existing heads. 039" gasket your CR will be approximately: 10. 0 rating. The head,s came off a 1972 Z28 which had flat top pistons added some 11. 68-73 76cc heads give about 11. 1 with 57cc heads it goes up to 9. 4 to 1 for compression. what i'm reading is that a 400 with the stock 24cc dish volume pistons with the 64cc heads would have a compression ratio of 9. 75:1 since it gives 74-75 a 10:1 rating. Dec 1, 2007 · I would lean towards 72-76cc chambers with flat tops and that cam. 6 or so. And finally, let's say that we use a Fel-Pro Z1142 head gasket that's 4. Apr 1, 2021 · -4. 64cc chambers, 1. 605'' Rods, . the intake ports on the heads are MASSIVELY gargantuan. A 12 cc dished piston with 76cc heads would be about 9. Dec 29, 2003 · Assuming a 350 SBC I played with a few more numbers. 018 thickness shim gaskets. Jan 23, 2007 · need the ball park figure of the conmpression rato with flat topsa nd 76cc heads Jun 24, 2020 · It is fairly late piston given the "newer" part number! Most likely to be a dished piston with 4 eyebrows, not 100% sure? Thanks, Gary in N. My heads are 64cc chambers. 7 thats saying that the motor is stock. 5 or even 10:1 with aluminum heads with heart-shaped chambers and flat top pistons. 6-10:1 and I did the math (the 9. With flat tops, 76cc iron heads, or 72/70 cc alluminum. 025 deck clearance and figuring 13cc for a dished piston, I come up with 8. . 039 head gasket, . I am also using 1. 1 to 1 One thing to keep in mind, all the heads can vary +/- 5cc from the above due to valve design, the depth the valves are installed, and factory variables. 5:1 compression ratio and would like to know if a larger Combustion Chamber with a flat top piston would be better than a smaller combustion chamber with a larger piston dish (d dish -18cc). Completed engine RB53111 Keith Black Flat Top Pistons 1974-1976 $ 738. 032 thick head gasket, a . There is a science in building an engine with flat top pistons, it's quench. . as noted 472: 71-73 / 76cc heads 8. 25-11. 025" deck height. 100" to create the larger chamber. The flow may not be what you want because of port sizing, but the valves may be close. I had a chart that would tell you what the estimated compression ration would be with various combinations, but I cantt find it now Apr 25, 2008 · 429 flat top pistons, 74cc heads? Pump gas OK? Save Share. With flat tops and figuring 5cc for the valve reliefs, I come up with 8. To convert from CC to cubic inches multiply CCs by . 6:1 actual Oct 2, 2015 · A flat top piston as I've described with the nominal . 028 thick and your stated 67cc head it puts you about 9. Goal is to have it pull to 6000 rpm run low 13's. 0:1 w/76cc Heads; Specifications: Part Type. A head with 190 to 210cc ports would work well with that cam, stall, and gear. 041" thick head gasket, a 0 deck height, and -6cc flat top piston Swept volume = 4. Get your pistons up at o deck there usually down . Aug 17, 2011 · Lastly there are more factors in determaining your compression ration than just combustion chamber size. -Mark Feb 19, 2000 · yep thats what i built, a low compression 347 shortblock making 8. WARNING: Motor vehicles contain fuel, oils and fluids, battery posts, terminals and related accessories which contain lead and lead compounds and other chemicals known to the State of California to cause cancer, birth defects and other reproductive harm. 025" Dome Volume: +4. With the stock flat top 4 eyebrow pistons your compression ratio was advertised at 10:1, and is probably actually a little less. Like. 71/72 LT1s flat top for there 9. Click this link, scroll down, click on the Compression Calculator link. Jul 20, 2005 · i am putting new heads on my 400 sbc and i was wondering what compression i would have if i went from the current 76cc head to a 64cc head. the rebuild kit comes with flat top pistons and the heads that i currently have (came off of the motor) are 76cc chamber heads with 1. 030'' Flat Top w/2 relief valves; Press or Floating Pin; Comp Ratio: 10. Apr 8, 2011 · sbc 76cc vs 64cc? This is a old thread but years ago I used 487x which are 76cc. Mar 24, 2017 · Since we don’t know much about your 350 small block, we’ll assume it employs the typical flat top, four eyebrow production pistons. Jul 10, 2006 · I'm running sportmans 2 on my 388 with flat top forged pistons but my block is zero decked. Sep 30, 2003 · The only things I did different was to use flat top pistons and the heads were smog 76cc chamber heads. May 29, 2006 · Compression is the volume of the cyl (including the heads) at the bottom of the stroke / volume of the cly (inclu heads) at the top of the stroke. has dish pistons right now and 882 heads. remember though there is a limit that pump gas can take and too much compression will cause denotation, although aluminum heads help Sep 25, 2023 · C3 Tech/Performance - Piston to Achieve 10:1 Compression - Need help finding the right piston to achieve 10:1 compression. 3 to 1. Hence the positive number in the calculator. Jul 7, 2006 · If 76cc is accurate, I only picked up an additional . This configuration is for 472 engines only, and gives you 10:1 compression with ’68-’73 76cc heads (i. I have a 350CI which currently has 8. 60 Camel Hump Heads 64cc (3782461), Blueracer Camshaft: Duration 230/230 @. 100" dome. Looking at hitting about 9. 6:1 with . 000" Connecting Rod (357ci) Deck Height: 9. 040, and . With a composition head gasket, the piston 0. An 305 engine with 5cc flat top pistons and 58cc chamber heads will have a compression ratio of 10. Made in USA Feb 20, 2014 · Trying to get parts around to build a 383 for my 85 Chris Craft. 18 compressed steel shim gaskets. May 21, 2009 · -3 cc on the pistons Fel-pro 1018 head gasket. 1416*3. Jul 17, 2023 · We have a . May 23, 2013 · I am trying to decide whether I should build the engine similar to an L79 with domed pistons and 10. I found a web site that said the 85 was 9. R. 94 heads with upgraded springs for a better than stock cam. Keith Black Hypereutectic pistons are favored for their improved power and reduced scuffing. S. If the piston deck height on your motor is, for instance, 0. To do so I am using a 1972 307 crank . Jul 24, 2000 · The 4 valve relief pistons are right at -6cc volume. 3 to 8. In 1975, Chevy started cutting corners on their heads to save a little weight. 5 with 64cc heads I would cc the domes to figure an Feb 18, 2009 · alright so the motor is going to be bored . 49:1 w/76cc Head Aug 31, 2014 · I'm planning on changing my 76cc truck heads to some aluminum 65cc AFR Eliminator Heads, i have flat top pistons with valve reliefs part# H860cp60 i believe the current compression ratio is 9. With zero deck height it calculates to 11. Looking to increase compression to 10:1 either will small chamber heads and factory dished pistons or to change to a flat top piston and 64cc heads. RB53116 Keith Black Pistons 9. 5:1 compression with 76CC heads. 74:1 If you are in that range (10. 2 compression ratio and with 76cc heads will have 7. 5 valves, decent ports, ok heads. 150” dome which is typically around -4cc volume, this would create right around 10:1 compression. 20:1 w/58cc Head,8. 030 over 350, . 2 to 1 , pistons with a 13 cc dish will be 9. 5 to 12:1 on the 74-75 engine, so that should be somewhere between 11 to 11. 2 to 1 , 50 cc heads give 12. 585") springs. Sep 26, 2016 · Here's what my spreadsheet says for a 355 with 64cc chambers: 9. 6 comp. 6 which with a cast iron head like the Swirl Port will want mid grade to premium fuel depending on geography, temperature and altitude. Choose a flat top piston and play with the Piston Down Bore number to get 9. Its 447 lift and 222 at 050 . With the 64cc heads you have now, you will not be able to find a piston with enough dish to bring the SCR down into pump gas territory because nobody makes a piston that will work with the short (5. 5/64'', 5/64'', 3/16'' ring grooves. 1 compression. Aug 22, 2010 · All of these engines had . Jun 4, 2011 · Get a Crane 274H06 or Isky Mega 270. Compression ratios are 10. Pistons were down in the hole. I plan on adding boost later about 10-12psi hence the lc setup, otherwise on n/a you want more compression because of the fact it makes more hp. 48", 72cc heads, . The cam that I am thinking of using is the GM 151. I used the Dyno2000 compression ratio calculator. Sep 6, 2021 · Upgraded Cylinder Heads for a Small Block Chevy. 5:1 compression. So much for the "high" compression motor I thought I was running. 021 head gasket. 0:1 with a . 480" Stroke w/58cc Heads: 11. 025 in the hole and using a GM 10105117 head gasket that is . 560 compression height, these have 1. Even if you have flat top pistons with valve reliefs, you need to add cc's. 028" gasket stock compression height pistons piston dish/valve relief----compression Sep 3, 2022 · The last SB400 (. 275" from top of piston; Valve relief depths, dual symmetric, . i bought the 76cc heads to put on a 383 i was gona build, butt got a 400 SBC for a fair price, and plans changed, and with all the car build stuff i need, (you know drive train & body work ect. 5:1 compression using inverted dome probe pistons. 50 exhaust Pistons: The standard stock dished with double valve reliefs. you'd be way better off with a 64cc head and a flat top or 1/8" dome piston JimM's firstgens. Mar 14, 2008 · Have not purchased anything yet, really wanted to stay with the Eagle competition 400 assembly, B12501 -5cc pistons ( 11. 015, 4. I think with the ported heads this engine will have around 370 HP . I will probably have them milled . 5 compression, if I can just use flat top pistons, that will be great. With the 280 cam the DCR was too high. I’m thinking 350-400hp, 224 to 230@. Ratio: 10. 000 Bore, 3. If the motor was rebuilt before than you will need to check to see if the pistons were replaced. 016") to bring the Dec 7, 2002 · 84 Z28 Camaro, 2 Seater Convertible, w/283 bored 80 over,flat top pistons, 2. ccso640. THe motor has dished pistons. Sep 26, 2018 · Keep the pistons you have and opt for a set of aluminum heads with 76cc chambers, for a 10. And you what to drop octane requirements a little bit. I plan to change to 64cc heads and a cam with . If you can use a little more cam (like 280* advertised, 230* @ . 700 RodBR Comp. If they were replaced with flat top pistons then the comp ratio would have increased to 9 or 9. 018 compressed steel shim gaskets. 225" deep Aug 5, 2001 · If you ran a flat top piston with 70 cc heads in a 383, you would get about 10. 74:1) it will be a bit too much compression for pump gas and iron heads (IMO). 5:1, your good deal will leave you unable to run any advance at all, richer than stink, and maybe with shattered rings and holes in your pistons, or paying $4/gl for race gas. 045" squish (measurement from the piston crown to the underside of the cylinder head with the piston at top dead center, including the gasket thickness). 5 vavles. These aluminum X-style 350 Chevy pistons are designed for shorter wrist pins, adding strength and weight 350ci Performance Pistons, . 33 Jul 13, 2020 · To the best of my knowledge, ALL GM 400 head castings had 76cc chambers, which makes and excellent combination when used with flat top pistons (with valve notches), which works very well with pump gas and produces about 10:1 compression (compression numbers may vary depending on conditions and modifications). When 94 SUNOCO was still available in Nj had not problems at all. No strokers allowed. 39 with 64 cc heads and 11 to 1 with 50 cc heads. 5 with 72cc heads 11. 040", having a volume of 9 cc's and putting the squish at 0. Honestly, even those are a bit big for that low CR, but much better than the ones you picked above. 030, . We used flat top, with valve notches, hypereutectic pistons and massaged factory SB400 heads that were opened up with stainless 2. Jun 25, 2009 · 425 heads should give it about 9. I had a hard time with detonation/pre-ignition. 025 in the hole you're static compression is 9. The listed CR is 8. 058 (0. Get your engine's optimal compression ratio and total displacement in no time flat! Just complete your engine setup, click calculate, and you’re on your way to maximum performance. 040" is ideal for flame travel during the combustion process. The cams remained the same. the other method above will work if you are positive the block Aug 9, 2003 · It could be as low as 8. Dec 8, 2004 · At 12. IMO AL Jul 11, 2014 · Talking to the guy that re balanced my crank and he suggested 76cc S&S Performance heads and superE carb to go with the 600 cam I'm thinking about. 9 / 1. If you figure that the dome is worth 7-10cc (negative when you figure the CR), with a . 6:1 A 350 bored 0. 6:1 compression depending on head gasket thickness and piston to deck distance at TDC. I figure with flat top pistons, compression should be 10:1 easy. Sort by Oldest first Oldest first Newest first Most reactions. 023 deck and 5cc valve notches, heres what your going to see in STATIC COMPRESSION,as a result of combustion chamber changes Jul 25, 2020 · BigBro74 wrote: ↑ Sat Jul 25, 2020 5:08 pm Here is a related question- I am contemplating a build for my niece for a ump “factory stock” class car. 039 rebuilder head gaskets and almost 9. Lots of static compresion. 32:1 advantage over the stock pistons according to the rough estimates provided by TRW on the web (8. Uses 1/16″ ring pack for reduced friction. 040 Bore, 3. A flat top piston with a 76 cc head would get you about 9. DO NOT USE ANY STOCK 75-LATER CHEVY HEADS ON A 400. L/48s used a dished piston. The best combination for 76cc heads will be flat top pistons. 030'' Overbore. th350 w/stage 2 shift kit 22-2500 stall. 025". but the question is. 060 over with flat-top trw cast pistons and 64cc heads. Using 64cc head chamber volume and . 61 with a dynamic CR of Speed Pro, Hypereutectic Pistons, Chev SB 350BR Chev 350, 4. Price includes pins. 8:1 for 472 W/76cc Heads 1968-1973 August 23, 2018. 04"-thick head gasket. 03:1. 025 or so if the deck hasnt ever been cut bring em up to 0 deck and use a . United Engine Machine Chevy 350ci Hypereutectic Pistons Flat Top. Dec 5, 2006 · Flat top pistons or flat tops with valve reliefs should run fine. 021 gasket. 030'' Overbore; Piston Dia. 7 (350) rods and flat top pistons, will produce about 9. then get a calculator and divide the pin hole measurement by 2 then add the other measurement to this. According to the way I remember those posts, the recommendation was to use flat top pistons and mill the D3's to the desired compression ratio. Motor Vehicles . 9:1 w/76cc Heads; Rings: 5/64'', 5/64'', 3/16'' Priced as Each, Sold as Set; Sep 21, 2009 · I'm thinking these numbers are based off stock motors. 030 over bore I can get 9. 030, stroke 3. I was advised to go with the 72cc heads rather than risk the 64cc head would detonation. 6 valves, guides and screw in studs and a Comp Cam hyd roller kit. 020 only Cad Company forged pistons – Flat Top – 9:1 compression for 500 CID Cadillac engines with 120cc heads (or 13:1 w/ 76cc heads). shorter version: ill be getting a 400sbc that is . 5 to 1. Anybody running these heads (the flat top piston version), although I'm not gonna get hung up on chasing numbers I'm hoping for about 100/100. 039 gasket-64cc head Thanks for all your help fellas, I ordered roller cam, heads and pistons today. This really isn’t bad. 050 Lift 480/480 109 degrees, Edelbrock RPM Maniford, Holley 670 Avenger Carb, Hooker Ceramic Coated 1 5/8 Headers, Pro-Built 700R4 Street/Strip Trans. 350" crate engines with dished pistons and 76cc heads giving about 7. This a street/strip car, 4. 714 Apr 18, 2012 · Based on a flat top piston with 6cc valve reliefs that is a typical . However, 76cc heads milled to 70cc equating to approximately 10. Option #2 Pro Comp Aluminum Heads, 190 cc runners, 64cc chambers, dished pistons. ----- Jul 23, 2012 · I currently have a 350 sbc 60 over with forged flat top pistons and stock crank and rods. Mar 27, 2011 · Lets talk flat top 350 pistons for my DD Jump to Latest 2K views 3 replies 3 participants last post by Wolfplace Mar 27, 2011 Nov 9, 2014 · Most pistons have enough flat material above the top ring lands to effectively make a decent squish. Even with a 268 cam it will be under 8:1 dcr. With a 0 deck and a . 7:1 with 76cc combustion chambers. 125" tall that mimics the old factory LT-1 piston for the 350), when used with a typical . DIAMOND FLAT TOP FE FORD 390 PISTONS Forged Stock Stroke and Stroker Ford 390 Piston Sets. 100-. 6-10 range is for any minor miscalculation). These pistons are intended for use with modern 1/16″ ‘skinny’ ring packages for reduced friction The cc for the piston is entered as a positive number on a -cc Dish or Flat top piston and a negative number on a dome piston. 025" with the new pistons, you might use a steel shim head gasket (0. Head gaskets: Standard thickness Felpro I can't think of what else you would need to know. This seems very confusing but it is because even though it is a -cc on the piston, those same cc's are gained in cylinder volume. 025" in the hole will net around 10. They will not perform as well at equivalent compression ratios. 6 compression with 76cc heads, correct? Is that with flat top or dished pistons? I'd like to go to about 9. 0 dome pistons in it and this one the best engine I built with stock heads. 020 down in the hole. a 64cc head and flat top piston in a 350 gets you about 10. 6 roller rockers, KB flat pistons, scat forged rods and cast crank. If I remember right, the last small block I built had 76cc heads and flat top pistons, and I think the compression ration was 9. with 76cc heads and 13 cc dished Apr 27, 2005 · Here`s where the fun part begins. Another 305 engine with D cup 12cc pistons with 58cc heads will have a 9. Jun 19, 2020 · for example, a common one right now. Mar 13, 2004 · Head gasket volume is published by the manufacturer. Jun 5, 2020 · I see that a very popular rotating assembly is the Eagle B13055E030 which includes KB flat top hypereutectic pistons with 7cc valve reliefs, decent rods and a cast steel crankshaft. Dec 8, 2005 · Those would likely be the original heads for a 1967 327-275 4 bbl motor. 9: Mar 13, 2012 · The factory 76 cc heads have a poor chamber design. 020-inch below deck, and a 76cc combustion chamber, and with a composition head gasket this puts the static compression at 8. You have to take into account piston volume (whether it has a dish which will lower compression, flat top with valve reliefs, or a dome which will increase compression), bore size, stroke length, and the camshaft. Are these heads upto that sort of output on a 97" motor? Aug 26, 2011 · Ideally, you want between 0. i have two options: run a set of vortec heads on the 408 with the stock dished pistons Oct 21, 2007 · I am building a 327 out of a 1971 350 block . e, rated 9. 6:1 with 58cc combustion chambers, 9. You need to know the piston compression height, volume of the valve reliefs, deck height and head gasket thickness, in order to make a better estimate. 8. What are the pros and cons of 64cc chambers with dished pistons versus 72cc chambers and flat tops? Nov 19, 2010 · Flat top. 4:1 if your block is undecked and you're using a standard 0. Flat Top Pistons; United Engine Machine Chevy 327ci Hypereutectic Pistons Flat Top. 5:1 with domed pistons, but would be OK with 9. Oh and full length headman headers. 041" thick gasket and a uncut block a 383 is still 11. Online CR calculator show this combo to produce about 10. Feb 11, 2012 · heads and cam Well for starters the 882 heads have a large chamber size of 76cc and they flow alright but hurt the compression of down to about 8. 5:1 CR 500: 71-73 / 76cc heads 8. It will give a lopey idle without totally killing performance, assuming you only have stock 76cc heads and dished or flat-top pistons (8:1-9:1 CR). 030",a stroke of 3. The included valve reliefs allow for much larger cams than stock, flat-top, or KB D-Dish pistons. 25 domed pistons . Aug 18, 2006 · But the heads are 75cc not 76cc heads ,and the pistons i have are advertised in jegs as speed pro cast pistons 345np40 ,not the hypers and it says in the desription 10. CR with head chamber of: Bore Size Piston Set Piston and Ring Kit; 58cc 64cc 76cc; 1. But, the '68-'70 heads had the same combustion chamber as the early low-comp engines they just used a different piston. 010" to basically leave the piston down . com Camaro Board Speed Pro, Hypereutectic Pistons, Chev SB 350BR Chev 350, 4. Chevy 327 Flat Top Pistons for use with 6. Jun 14, 2013 · For a example a 350 std bore with flat top pistons with 5. They assumed that the pistons were flat top. 020 deck height). Then change the head to 64cc and the gasket to . 040" Compression Distance: 1. 050 range one on a 110 and the other on a 105 or 106 I believe. The included valve reliefs allow for much larger cams than stock, flat-top Dec 26, 2001 · The STOCK 70-74 heads, which are 76cc heads, used with 5. These T-5 heat treated pistons also offer reduced thermal expansion, which allows you to run tighter clearances and allows the piston rings to seal better and minimize Aug 29, 2001 · Does anyone know if the pistons are Flat Top or Dished Pistons? Anyone want to guess what the new compression ratio is ? I know after reading"How to rebuild your Small Block Chevy" by Dave Vizard that a guide would be: F/T pistons with 64cc chamber volume Heads (Trickflow 23) would be @ 10. Jul 25, 2020 · I’ve got a few sets of useable iron 76cc factory sbc heads left that I would eventually like to use on something. I plan on using the the stock 1. Nov 19, 2008 · lets look at your question, given identical 350 displacement engines with flat top pistons and a common . 2 Jul 19, 2012 · I figured it out with a typical flat top piston with 4 valve reliefs, undecked block and stock head gaskets and came up with about 9. Cylinder Head, Iron Eagle SS, Cast Iron, Bare, 76cc Chamber, 170cc Intake Runner, Chevy, 1987-95 305/350, Each. 061 Here's an example: a 355 cid engine has a bore of 4. 5:1. 000 Rod. e. Dec 1, 2007 · OEM constructed flat top pistons have 4-valve reliefs, and the piston skirts are diamond machined to assure that clearances are half that of industry standards. If you ran a flat top piston with a 64 cc head your compression ratio would be about 11. 6 However if you have domed pistons the compression gain would be much higher. Keith Black Hypereutectic Piston (flat top) for Cadillac 500 Engines, with pins. 2 to 1 or somewhere in that area. gota try to use whats paid 4) i want/need to use Dec 15, 2000 · Without going into a long post on engine building, don't do dome pistons with a 76cc head. 020 destroked" meaning, it has . 1182 posts . 25-10. SO, the compression is up there for pump fuel, which is what I use. 28:1 SCR. 038 gasket plus estimated 0. These pistons are not compatible with any off-the-shelf aluminum heads. The "LARGEST" Benefit the flat top piston will have is "flame travel" And if in the future you use a upgraded head with a better combustion chamber you will benefit even more. 490, 1. 060 over and with flat top pistons, i believe a 76cc head will leave me with lower compression than i want, but i think putting vortec heads on the thing which are 64cc heads will make Jun 24, 2012 · what i have is a 72 chev 350 4 bolt,278 cam, flat top pistons. 6 to 1 on 64cc ). 038 compressed gasket. That's good enough for me. May 21, 2008 · I assume your current heads are 76cc (before shaving). 72cc heads makes it work. Jan 16, 2012 · the motor was running with . Y. 75, head chamber 64, piston dome -4 (for valve reliefs), gasket thickness 0. 8:1 compression with ’68-’73 76cc heads (i. Keep us posted. 030 over) I built was about 2yrs ago for my son's 73 Corvette. 25:1 w/64ccBR Ideal for street performance, brackets, and oval track claimers. 028 gasket having a compression ratio of 9. ’74-’76 500), or 14:1 compression with ’68-’73 76cc heads (i. Bores: Standard size Block has not been milled or decked. 48 or 44. 79:1. Nov 13, 2004 · I know I'll find out when I get the heads off, but I like to start the build planning now. 1 Compression (i. 265" Crankshaft Stroke/Rod Length: 3. I am sure this topic can go both ways but my preference for street performance would lay with a flat top. Oct 15, 2003 · or if you have a piston out of the block you can measure the wrist pin hole with a dial caliper, write this number down. not all 76cc heads are junk. 2 compression ratio. Speed Pro, Hypereutectic Pistons, Chev SB 350BR Chev 350, 4. The cam is a 214/224 cam. With the composition head gasket I get a static CR of 9. flattop 350 with 76cc Aug 13, 2006 · I have 200cc dart iron eagle heads (72cc) with flat top pistons and only have pinging if used with below 93 octane or old gas sitting in the tanks too long. 030 to raise compression to 9. Aug 18, 2008 · Back in the day of domed pistons, that was no big deal with high octane gas. 035" and 0. If deck was just cut . Thanks Steve. 5:1 CR . As far as flame travel or the mixture burn , A flat top would provide a better more evenly applied burn across the top of the piston in my opinion. In the summer I have to run 92 octane with about 5 gallons of racing fuel just to help on pinging. Stall is between 1700 and 2000. 060 with a zero deck height, flat top pistons and 76cc heads would have: Aug 6, 2024 · 460ci Performance Pistons, w/6. 050) or a dished piston the Vortecs would be fine. 30 over i was going to use the stock gm heads (supposed to have been reworked with triple ground valves and z28 springs)but i doubt it. By changing to 64cc, what would be a rough estimate of my compression ratio? Aug 4, 2005 · Hippie, your killing me here, with all this anti 76cc head stuff :sweat: i need a 76 cc 400cid motor combo thats gona move my 63 Nova, 350 375 HP range. Domed pistons were all gone even on the 71 LT1. My heads are 10 ccs bigger than yours so, U probably would be better off using dished pistons. I'm looking for a streetable "pump gas" engine with compression around 9. Apr 6, 2003 · I have seen D3 heads recommended on this board because they have (I'm going by memory) the same shape closed chamber as the D0 heads with the roof raised . Nov 13, 2013 · With a 64cc head this engine will only be 9:1 comp. You'll want to be atleast 9. With coated skirts. On today's gas I'd be worrried about anything over 8. 7 compression ratio. The correct quench of about . This piston is the one found in the #19355658/290 HP crate motor sold by G. Great news: S&S heads are now available to be used with stock-style flat-top pistons! The kits are fully assembled and come with stainless steel valves and high-lift (. Good luck Apr 2, 2015 · This is where I start as well 2-eyebrow flat top piston if possible stock 'compression height' pistons (usually KB's) with proper 'engine quench' distance adjust from there if needed to make the combo work although the stock open chamber 76cc heads did tend to allow better valve flow than the stock closed chamber 64cc heads but were usually used in an ultra low compression Jan 1, 2014 · With 76cc head on a 350 with flat top pistons you going to see 8. 55:1 compression. then measure the distance from the top of the wrist pin hole to the top of the piston and write this down. 4:1 or 10. Not sure, but I think AFR is the only manufacturer that make s 76cc chamber aluminum head with 190 to 210cc ports. Not ideal unless you running a very mild cam shaft. 5cc (from the KB website for their flat-top 4 valve relief pistons, they show cc's of 6. 385: 463 / 132-4. 040 gasket and keep This configuration is for 472 engines only, and gives you 9. so even with a zero deck height, it would still be . The included valve reliefs allow for larger cams than stock or flat-top pistons. Just some info. Thing was a bear. No valve reliefs. This is the factory 327 350 HP cam . The benefit to the flat top piston with only 2 valve re-leafs is a little compression. 5:1 on the 76 IF the block and/or heads have not been shaved. Thea are a 3200 lb car and the engine is is limited to 358” and open chamber heads / no porting/ flat top pistons/ iron 2bbl intake/ pen 2bbl like rochester/ Hydraulic Flat Tappet cam. Part Number: DRT-10024364 Not Yet Reviewed Mar 31, 2005 · Dart Iron Eagles, 200cc runners, 72cc chambers, flat-top pistons. A dome piston will just Silvolite Cast Replacement Pistons With pins available in . 02/1. 79. 5 compression flat top pistons with 1973 stock 76cc Iron Heads. with a 76cc head, this MAY make it a dished deal! Mar 3, 2005 · Such a piston would shrould the valves badly, reduce flow and VE, and probably be prone to pinging. It has stock 76cc heads. Dyno tests by David Vizard and others have shown conclusively that the tighter the squish, the more power the motor makes and the less choosy it is about fuel quality, up to the point of piston/head interference anyway. 3 to 10. 2:1 with 64 cc heads thats why i bought these instead of the hypers because the were advertised with slightly more compression. 75:1. This configuration is for 500 engines only, and gives you 10:1 compression with ’68-’73 76cc heads (i. 1 motor because i want to upgrade to a bigger cam it has a lunati S&S Cycle - 76cc High Compression Performance Cylinder Heads fits '84-'99 Evolution Big Twin Models - Natural. Find CP Pistons 350 Chevy Flat-Top X-Style Pistons and get Free Shipping on Orders Over $109 at Summit Racing! Super-lightweight forgings with exclusive machining techniques and processes make CP Pistons 350 Chevy small block flat-top X-style pistons lighter without compromising strength. 76cc combustion chamber. : 4. Edelbrock RPM performer intake and hei distributor and MSD box. P. My 72 351c 2v should be @ 8. 480" with 6. 060 over. 10 gear,fiberglass front end. The Lingefelter book on small block chevy says they are the best flowing 76cc head available. 5:1 static compression ratio with 64cc heads. 9:1 with 64cc combustion chambers and 8. Oct 11, 2002 · I have a 327 bored . In 75 the heads had a second exhaust crossover port added which produced more head heat. 9cc Compression Ratio: 3. L82s showed up in 73 same forged flat top piston. 39:1 to 10. Dec 30, 2009 · Heads: 14101081 305 58cc 1. 65:1. Dec 1, 2004 · I still have the heads (never used them) as I installed AFR heads immediately after I received the engine. May 18, 2011 · With 76cc heads, . 050 intake duration stuff for some budget street builds. Ratio is about 9. The most efficient at power and reducing detonation is a flat top piston with minimum deck clearance. Will work with OEM 390 - 428 FE heads or Edelbrock aluminum FE heads; Can be used with small nitrous kits, pistons made of 4032 alloy; Top ring is down . 4:1 w/62cc Heads; 10. Jan 1, 2018 · Go with new flat top pistons. 94\1. Bore: (diameter) Feb 2, 2012 · Holley 670 SA, Edlbrk Airgap intake, Comp XE Cam Advertised Duration 274/286, Lift . 56 gear, 4k converter, vic jr intake etc etc. 0:1. so going . Assuming your 350 small block Chevy is using flat top pistons with valve reliefs, a cylinder head with a smaller 64cc chamber will immediately help by adding compression. 490/. Changing from 76cc heads to 64cc head was an increase from 9. M. i know i will have to change the intake manifold. 030 over-bore D3 with 95cc 9. New rings as well and get them pressed on. 5 points of compression between 64cc and 76cc heads on a 350, without other changes. 04 flat top pistons-zero decked block-0. but that same flat top piston and 64cc heads in a 383 stroker just pushed you up over 11:1 compression. Here are some pictures for reference. 52:1 w/76cc heads). Nov 7, 2012 · Here is some examples. 5. Does anyone have any idea about what the compression ratio would be with flat top pistons? To be honest I do not remember if the standard pistons were flat tops or dished pistons when I tore it down 4 years ago. 2:1 w/64cc; 9. Im not sure of the stock compression ratio but i think its 9:1 (each piston has a 9 stamped in it). It would be helpful to know which GMPP crate engine? Assuming this is an unmolested block with . 100" x 0. 5 cc reliefs and 64 cc with a steel shim . I was disapointed that the engine had dished pistons as that caused the 68cc chambers in the AFR heads to result in a lower compression than AFR told me I would have. ’68-’73 472). 025 inch between the piston and deck with the former at TDC and 12 cc factory pistons the compression ratio with 64 cc Vortecs looks like this: Feb 9, 2011 · In rough terms, you would need a domed piston with the 76cc head to equal a flat piston with the 64cc head, or a flat piston with the 76cc head to equal a dish piston with the 64cc head - depending on what the target compression ratio is. ) - Holley 600 cfm carb, - Edelbrock EPS Performer intake I can not find them. 020 off the top of the piston, where a normal 350 piston would have a 1. 025 deck and a . Good chambers, ports, and valve job, and they are a tall port head. 420 lift on both intake and exhaust. 5-11/1 compression and use an l79 style "151" grind camshaft or should I just use 9-1 flat top pistons and use a slightly more modern cam like High Energy 268 or Elgin E-1065-P. Sep 13, 2002 · Stock engines also had dished pistons along with the 76cc heads which made for the 8. And a set of full ported 882 76cc heads . The combustion chamber is the combination of the head and the piston. 1:1 with the standard . -----70 nova w/350,th350 2800 stall,76cc heads 487x,very mild cam,edelbrock 750,weiand stealth,1 5/8 headers,4. The unique design & manufacturing processes combine to produce a rigid piston, which will rock less in the bore improving ring seal. 700 Rod, Flat Top, 4 Valve Relief, 9. Aug 9, 2012 · A reverse dome would be best imho . 94/1. 00. can i use the existing pistons? or is the This configuration is for 500 engines only, and gives you 10:1 compression with ’74-’76 120cc heads (i. These pistons are compatible with standard ring packages, but require a unique top ring gap. So, you need a 76cc aluminum head. Aug 2, 2014 · The most accurate way to know for sure is to 'CC' the piston in the block @ TDC, then 'CC' the combustion chamber in the head with the valves you are going to use in that head pocket. Jul 5, 2005 · MI2600, that seems really low for a 383 with flattops and 64 cc heads. 84 intake / 1. It is listed as having an 8:1 C. 125”-. These pistons are intended for use with modern 1/16″ ‘skinny’ ring packages for reduced friction Keith Black Hypereutectic pistons are favored for their improved power and reduced scuffing. 5 comp ratio. ----will change your CC number. Standard milling can further change the cc up to -6cc. These T-5 heat treated pistons also offer reduced thermal expansion, which allows you to run tighter clearances and allows the piston rings to seal better and minimize Dec 11, 2011 · You didn't say what the dish cc's are in your pistons so I used 6. If you are going to run a high lift cam, flat top pistons with eyebrows may need to be flycut. Jun 8, 2005 · A 350 with a zero deck height block (block deck cut so the piston is flush with block), flat top pistons and 76cc heads would have: (727 + 76 + 8 + 1) / (76 + 8 + 1) = 812/85 = 9. This is a premium gas motor. 76cc, 1. Mar 19, 2004 · I think I can answer my own question. 040 BoreBR Chev 350, 4. The 345NP piston, is ". 5:1 on a hot street engine with a performance cam. ocyzbf nmh rgouj aafr gciffp zztmogn ydrusli ehbwej lwhd dxxqa