6 bolt heads?
Team Owner
Joined: Nov 2007
Posts: 24,035
Likes: 2,342
From: Gilbert AZ
More HP level as boost depends on motor/etc. 30psi on a 346 could be 20psi on a 440ci.
Honestly this is getting tougher to answer. I've seen 1300+rwhp out of 4 bolts. The key is good studs, good gaskets, and thick deck aftermarket heads. Plenty of cars making 1200+hp on 4 bolts running fast times.
Honestly this is getting tougher to answer. I've seen 1300+rwhp out of 4 bolts. The key is good studs, good gaskets, and thick deck aftermarket heads. Plenty of cars making 1200+hp on 4 bolts running fast times.
Safety Car
Joined: Dec 2009
Posts: 4,754
Likes: 303
If you're running a good 4 bolt head like the LSA casting, it could probably do 1,000+whp / 20psi+
Around 1,200+whp / 20-25psi you might want to put a 6 bolt head on a 4 bolt motor for the extra deck and strength
Above 1,300+whp / 25psi+ it would probably be best to run a full 6 bolt combo
All I can say from experience though is that the LSA/4bolt setup works fine for me at 915+whp/20psi
Around 1,200+whp / 20-25psi you might want to put a 6 bolt head on a 4 bolt motor for the extra deck and strength
Above 1,300+whp / 25psi+ it would probably be best to run a full 6 bolt combo
All I can say from experience though is that the LSA/4bolt setup works fine for me at 915+whp/20psi
Thread Starter
Burning Brakes
Joined: Sep 2006
Posts: 1,099
Likes: 33
From: Knoxville TN
Thanks Unreal! How did your build end up? I am wanting to do similar build to yours. I am just in the thought process right now. I currently have A&A V3 t-trim on stock bottom end 08 ZO6. Its got WCCH ls7 4 bolt heads, and I really want to just run what I have in heads, but with 1/2 studs with ERL bottom end. My current setup is making 740 RWHP with a very safe tune, on 8 psi.
Team Owner
Joined: Nov 2007
Posts: 24,035
Likes: 2,342
From: Gilbert AZ
Thanks Unreal! How did your build end up? I am wanting to do similar build to yours. I am just in the thought process right now. I currently have A&A V3 t-trim on stock bottom end 08 ZO6. Its got WCCH ls7 4 bolt heads, and I really want to just run what I have in heads, but with 1/2 studs with ERL bottom end. My current setup is making 740 RWHP with a very safe tune, on 8 psi.
I would sell the heads and go with a 6 bolt head, the thick deck is what keep them from flexing. Then again, if all you want is 900 or less they are fine. If you want 1000+ then I would get a thicker deck head.
Just get a nice build bottom end and enjoy it. Heck, just pistons/rods and 800rwhp is perfect for a z06 IMO.
Drifting
Joined: Nov 2011
Posts: 1,267
Likes: 1
blue by u- nice setup.. thought this might help ya.. i was thinking of getting a erl shortblock as well for my setup.. ive got a 613rwhp hci c6 z06 that i thought of doing a sb and t or ysi trim on.. ive got the wcch heads too..
Talked to ERL and bc i kinda wanted to stay under 1k rwhp and use my wcch heads, they suggested me getting the 6 bolt block and that way i could always sell the wcch heads down the road if i wanted ot up the power or somethin.. they said the 4bolt heads will boltup to the 6 bolt block..
good luck with whatever you decide!
Talked to ERL and bc i kinda wanted to stay under 1k rwhp and use my wcch heads, they suggested me getting the 6 bolt block and that way i could always sell the wcch heads down the road if i wanted ot up the power or somethin.. they said the 4bolt heads will boltup to the 6 bolt block..
good luck with whatever you decide!
Burning Brakes
Joined: Aug 2009
Posts: 841
Likes: 0
From: DFW Texas
These are all good suggestions but none of them mean anything if you don't have a good tuner. I've seen ls3 cars push water making 640 rwhp with a incompetent tuner. We have a Cts-v with twins at the shop now making 1160rwhp with a stock LSA head. While good head studs and ls9 gaskets are a given, you better find yourself a good tuner to go along with it.
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Thread Starter
Burning Brakes
Joined: Sep 2006
Posts: 1,099
Likes: 33
From: Knoxville TN
blue by u- nice setup.. thought this might help ya.. i was thinking of getting a erl shortblock as well for my setup.. ive got a 613rwhp hci c6 z06 that i thought of doing a sb and t or ysi trim on.. ive got the wcch heads too..
Talked to ERL and bc i kinda wanted to stay under 1k rwhp and use my wcch heads, they suggested me getting the 6 bolt block and that way i could always sell the wcch heads down the road if i wanted ot up the power or somethin.. they said the 4bolt heads will boltup to the 6 bolt block..
good luck with whatever you decide!
Talked to ERL and bc i kinda wanted to stay under 1k rwhp and use my wcch heads, they suggested me getting the 6 bolt block and that way i could always sell the wcch heads down the road if i wanted ot up the power or somethin.. they said the 4bolt heads will boltup to the 6 bolt block..
good luck with whatever you decide!
Thread Starter
Burning Brakes
Joined: Sep 2006
Posts: 1,099
Likes: 33
From: Knoxville TN
These are all good suggestions but none of them mean anything if you don't have a good tuner. I've seen ls3 cars push water making 640 rwhp with a incompetent tuner. We have a Cts-v with twins at the shop now making 1160rwhp with a stock LSA head. While good head studs and ls9 gaskets are a given, you better find yourself a good tuner to go along with it.