Aftermarket heads cc size for boost? - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

_Onyx_Wolf_ · 09-23-2019, 10:12 PM

Looking at doing a agp twin turbo setup next summer and wanted to get a set of Texas speed prc 260 aftermarket heads before then. I’m stuck on what CC to choose for boost, does this affect compression? I want to run high boost on 93 with meth no e85 because they don’t carry any in my area. And Later down the line doing a forged 416 with dart sleeves. Current setup is bolt ons,gpi rod mod,bo white stage 3 throttle body, and a stage 3 tick polluter cam.

G8One2 · 09-24-2019, 04:44 AM

Yes, cc effects static compression. You have to do all the math on your particular setup to know if a specific cc aftermarket head will work with what you've got. Stock heads are 70cc

1fast · 09-24-2019, 10:27 AM

http://www.libertyperformance.com/pr...on-chamber.php

Ran these on high boost ls3 24 lbs long runners made great power got them at . outcasttuner.com

hillshooter · 09-24-2019, 10:30 AM

stock is 68 and some people call it 68.5 . If you are changing heads only then its very hard to affect compression ratio, 72 is about the biggest you will see, that 4CC is nothing. Pistons are the easy way to lower compression, they make all kinds -2 -4 -10 -15 -20 and so on. if you are forging later then just do stock now so the math stays easy when you select a piston later.

BTW my 418 is 68CC chambers with a -15 dish piston and I am 10:1 CR

_Onyx_Wolf_ · 09-24-2019, 10:59 AM

Quote:

Originally Posted by hillshooter

stock is 68 and some people call it 68.5 . If you are changing heads only then its very hard to affect compression ratio, 72 is about the biggest you will see, that 4CC is nothing. Pistons are the easy way to lower compression, they make all kinds -2 -4 -10 -15 -20 and so on. if you are forging later then just do stock now so the math stays easy when you select a piston later.

BTW my 418 is 68CC chambers with a -15 dish piston and I am 10:1 CR

Sweet thanks and which compression would you recommend for 93 octane only with meth running maybe 20-25 lbs

jeff657756 · 09-24-2019, 11:39 AM

Quote:

Originally Posted by _Onyx_Wolf_

Sweet thanks and which compression would you recommend for 93 octane only with meth running maybe 20-25 lbs

Hope this isn't on a stock block? I know you mentioned a 416 but doesnt sound like you are going that way immediately. You aren't going to want to go more than MAYBE 12-14 lbs with meth. I dont turn mine up more than 10 on just 93 and am usually around 13-14 lbs on E85.. Honestly new heads is the last thing i would be looking to buy if rear end/fuel system isn't done yet.

justinj · 09-24-2019, 01:39 PM

If you are getting Dart sleeves just go 427 and send it. That’s what I’m doing. Price difference is very little if any. I going with a dart block and skipping the sleeves. It Will be a bit heavier but I think it will hold boost better and be a solid setup. Check out TMS new set of heads. Looks killer and price is on point.

ttshovel · 09-24-2019, 02:00 PM

Never understood why people think that a boost number is relevant to a motor living. A lot more goes into it than that. People have no issues on stock ls3 sleeves until around 1000whp. The tune has more to do with it living than anything.

To the OP, get the heads as large of a chamber as possible, especially being limited to pump gas. The ls3/l99 have plenty of static compression

G8One2 · 09-24-2019, 02:26 PM

Quote:

Originally Posted by hillshooter

stock is 68 and some people call it 68.5 . If you are changing heads only then its very hard to affect compression ratio, 72 is about the biggest you will see, that 4CC is nothing. Pistons are the easy way to lower compression, they make all kinds -2 -4 -10 -15 -20 and so on. if you are forging later then just do stock now so the math stays easy when you select a piston later.

BTW my 418 is 68CC chambers with a -15 dish piston and I am 10:1 CR

Yep your right, 68cc is correct. I was thinking the L92 which are 70cc, I stand corrected.

bct10985 · 09-24-2019, 02:39 PM

https://ls1tech.com/forums/forced-in...t-heads-3.html

_Onyx_Wolf_ · 09-24-2019, 05:04 PM

Quote:

Originally Posted by jeff657756

Hope this isn't on a stock block? I know you mentioned a 416 but doesnt sound like you are going that way immediately. You aren't going to want to go more than MAYBE 12-14 lbs with meth. I dont turn mine up more than 10 on just 93 and am usually around 13-14 lbs on E85.. Honestly new heads is the last thing i would be looking to buy if rear end/fuel system isn't done yet.

No that’s when I have the resleeve 416 lol

hillshooter · 09-24-2019, 05:46 PM

Quote:

Originally Posted by _Onyx_Wolf_

Sweet thanks and which compression would you recommend for 93 octane only with meth running maybe 20-25 lbs

I dont think you can run that kind of boost at all. stock ringland gap is an issue, 93 is garbage, compression is the least of your worries.

AGP Turbo · 09-26-2019, 03:24 PM

Don't waste your money on heads. Bone stock LS3 heads will easily get you to the limit of an aluminum block (weak point is not the sleeves). And don't bother sleeving a stock block, that's a waste of money too. 416 built about 9:1 with your current heads and ARP head studs will get you to the limit of 93oct north of 900whp/900wtq and be nice and lite weight doing it.

ttshovel · 09-26-2019, 04:10 PM

Quote:

Originally Posted by AGP Turbo

Don't waste your money on heads. Bone stock LS3 heads will easily get you to the limit of an aluminum block (weak point is not the sleeves). And don't bother sleeving a stock block, that's a waste of money too. 416 built about 9:1 with your current heads and ARP head studs will get you to the limit of 93oct north of 900whp/900wtq and be nice and lite weight doing it.

4 inch stroke in a stock block isn't a great idea

Yes, sleeves are an issue... along with cap walk, 4 bolt heads, and a weaker aluminum casting altogether

09-23-2019, 10:12 PM	#1
_Onyx_Wolf_ Onyx_Z7 <— Instagram Drives: 2013 2ss 1le Join Date: Aug 2014 Location: Delaware Posts: 634	Aftermarket heads cc size for boost? Looking at doing a agp twin turbo setup next summer and wanted to get a set of Texas speed prc 260 aftermarket heads before then. I’m stuck on what CC to choose for boost, does this affect compression? I want to run high boost on 93 with meth no e85 because they don’t carry any in my area. And Later down the line doing a forged 416 with dart sleeves. Current setup is bolt ons,gpi rod mod,bo white stage 3 throttle body, and a stage 3 tick polluter cam.

09-24-2019, 10:27 AM	#3
1fast 8.60 @ 157 @ 4200lbs Drives: 2010 Gen 5 Join Date: Nov 2013 Location: Warrenton, va Posts: 299 View My Garage	Heads http://www.libertyperformance.com/pr...on-chamber.php Ran these on high boost ls3 24 lbs long runners made great power got them at . outcasttuner.com __________________ 2010 camaro twin turbo 8.60 @ 157 full weight 4200

09-24-2019, 10:30 AM	#4
hillshooter Drives: 2015 Camaro SS commemorative Join Date: May 2015 Location: Utah Posts: 425	stock is 68 and some people call it 68.5 . If you are changing heads only then its very hard to affect compression ratio, 72 is about the biggest you will see, that 4CC is nothing. Pistons are the easy way to lower compression, they make all kinds -2 -4 -10 -15 -20 and so on. if you are forging later then just do stock now so the math stays easy when you select a piston later. BTW my 418 is 68CC chambers with a -15 dish piston and I am 10:1 CR __________________ 2015 Camaro SS, LS3 Stroker, PRC heads,CUSTOM CAM. AGP 68/68 with custom Hot and Cold side. Fore triple pumps, Holley terminator X. BMR drag suspension with carlyle brake kit. 15" ET drags and 17" skinnies. ZL1 3.73 gears , aluminum driveshaft. TH400 with circle D converter.

09-24-2019, 01:39 PM	#7
justinj Drives: 2011 CAMARO 2SS RS Join Date: Sep 2013 Location: Moreno Valley Posts: 129	If you are getting Dart sleeves just go 427 and send it. That’s what I’m doing. Price difference is very little if any. I going with a dart block and skipping the sleeves. It Will be a bit heavier but I think it will hold boost better and be a solid setup. Check out TMS new set of heads. Looks killer and price is on point. __________________ 2007 GMC stock 2011 CAMARO 2SS RS-kooks long tube/flow-master American Thunder full exhaust, duel electric cutouts, Mcleod RXT, ZL1 3.73 kit, PFADT sway bars, Toe rods, Lowering springs, Trailing arms, solid rear cradle bushings, BMR motor mounts, Stage 7 RPM TR6060, Whipple Supercharger, LPE twin fuel pumps, ID850 injectors, Elite Catch Can, VEI Gauges, Blower Cam LS1 277LCB HR-14, Barton Short Throw Shifter. Widen Stock rims with 315s, Lots more. 615rwhp 530 rwtq on mustang dyno

09-24-2019, 02:00 PM	#8
ttshovel Drives: 12 camaro ss, 72 chevelle, 91camaro Join Date: Dec 2013 Location: findlay,oh Posts: 2,069	Never understood why people think that a boost number is relevant to a motor living. A lot more goes into it than that. People have no issues on stock ls3 sleeves until around 1000whp. The tune has more to do with it living than anything. To the OP, get the heads as large of a chamber as possible, especially being limited to pump gas. The ls3/l99 have plenty of static compression __________________ 12 camaro ss 427lsx, th400, f310 heads, crower shaft mounts, gpi specd solid roller, shearerfab 2k hp a/w, twin bullseye 88mm turbos, hughes pro ssx bolt together converter, holley dominator, 8.50 cert, backhalf, Ford 9", 33x17x16 tires, c16 fuel

09-24-2019, 04:44 AM	#2
G8One2 Drives: 2014 Camaro 2SS Join Date: Feb 2015 Location: Metro Detroit Posts: 492	Yes, cc effects static compression. You have to do all the math on your particular setup to know if a specific cc aftermarket head will work with what you've got. Stock heads are 70cc

09-24-2019, 02:39 PM	#10
bct10985 Drives: 2010 2SS LS3, 2013 duramax Join Date: Nov 2012 Location: Dover, De Posts: 1,451	https://ls1tech.com/forums/forced-in...t-heads-3.html __________________ ECS Ysi-B, cam, Tsp 2" longtubes, Squash dual pumps, Id1300s, meth, 4L80e, FTI 3600, ZL1 3.73 diff, BMR suspension, 15" conversion, weld rts mt 275 et street R. 9.6@147mph

09-26-2019, 03:24 PM	#13
AGP Turbo Drives: All things Turbocharged Join Date: Dec 2010 Location: AZ Posts: 1,199	Don't waste your money on heads. Bone stock LS3 heads will easily get you to the limit of an aluminum block (weak point is not the sleeves). And don't bother sleeving a stock block, that's a waste of money too. 416 built about 9:1 with your current heads and ARP head studs will get you to the limit of 93oct north of 900whp/900wtq and be nice and lite weight doing it.