Setting up Compression ratio !!
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Setting up Compression ratio !!
My motor is 02 LS1 with 40k on it, and we are installing twin turbos on it. The motor is not going to see anything over 8 PSI since I know the stock bottom end can't handle it. I'm going to build a new motor next year but for now I like to play with what I have and get the car running again. I’m installing MTI G1 cam and their valve train parts, ARP Head studs, and ARP rod bolts to keep the motor last longer a bit.
So now I want to drop the compression and I'm stock. I have been reading and a lot of people’s posts and they say for street car and Auto-x car (no drag) keep it at 9.1 ~ 9.5 CR. I like that since I don't want to loose the bottom torque when the car is not on the boost and pump gas is the only option for now.
But what is the best way to achieve that number? I want people’s opinion on this I know I can get thicker head gasket, and get very close but again some people say that is not the best option.
So any help here is more than appreciated?
So now I want to drop the compression and I'm stock. I have been reading and a lot of people’s posts and they say for street car and Auto-x car (no drag) keep it at 9.1 ~ 9.5 CR. I like that since I don't want to loose the bottom torque when the car is not on the boost and pump gas is the only option for now.
But what is the best way to achieve that number? I want people’s opinion on this I know I can get thicker head gasket, and get very close but again some people say that is not the best option.
So any help here is more than appreciated?
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You can buy some large chamber heads like 72cc patriot or afr. Then you have good heads to use on the built new motor. I would not waste my time going into current engine with cam or rod bolts. Just stick to 7 to maybe 8 tops and you should be fine. 5 psi if you really want to be safe. Why waste any time at all on current engine.
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I guess, that's what I'm going to do!! Sine I already have a spare block so might as well put together a new engine,
What do you guys think about this combo,
LS1 Block,
Stock Crank,
Diamond Forged -8.6 Dished pistons
Callies Compstar connecting rods
MTI G1 Cam 228/232 .588 .575 115
Patriot LQ9 Stage 2 or ET heads !!
So you guys think that cam would work with twin turbo setup or I should change it??
What do you guys think about this combo,
LS1 Block,
Stock Crank,
Diamond Forged -8.6 Dished pistons
Callies Compstar connecting rods
MTI G1 Cam 228/232 .588 .575 115
Patriot LQ9 Stage 2 or ET heads !!
So you guys think that cam would work with twin turbo setup or I should change it??
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I think the cam choice is not as critical as some think. That said I have gravitated to the lingenfelter cams which I am pretty sure are just custom comp cams made for lingenfelter. I figure lingenfelter guys know a thing or two about turbo cars. I currently have a gt7 not installed to use if want to but since going to a 408 most likely think might go up to a gt11. I am not sure about valve spring life with this cam though. Its near .650 lift and don't want to change out springs every 10,000 miles or something so might still go with milder gt7. Heads are also not as critical its going to push thru them anyway but the better flowing heads should give same power at smaller boost levels.
Sure you combo will work great. The key is forged parts. Remember though as said before more displacement should give more torque ,which is nice off boost and should spool up turbos at lower rpm than smaller engines. This might cause more traction problems though but you can get variable boost controllers to help that.
Sure you combo will work great. The key is forged parts. Remember though as said before more displacement should give more torque ,which is nice off boost and should spool up turbos at lower rpm than smaller engines. This might cause more traction problems though but you can get variable boost controllers to help that.
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Thanks, Maybe I should have said the car is not going to see any drag strips, it’s a Drift, Auto-x car. The only reason I asked we got this cam for another combo and showed up a tad late so I can either send it back or use it for my setup.
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I was checking out some of the sponsors’ sale and there is only $1200 price difference between 347 and 402 (Alum) for someone like me who has to buy new heads either way, so would it be good idea to save up and go with 402? Also you guys think I could use the cam I have or it's too small for 402?