I am in the process of building an engine. I am curious of what compression ratio people are having good results running. Yes I know it maters on a lot of factors. I am looking for some input from people who have build an engine with aftermarket pistons. Engine is going to be FI from a 72/75 turbo. It is going to be a 3.800” bore, stock 243 heads. I am down to two options for the forged rotating assembly.

1) 10.1 compression on a 4” stroke

2) 9.6 compression on a 3.622 stroke

I am woundering if anybody else thinks the 10.1 is going to be to high for a turbo. It is going in a pre runner style truck. That is daily driven. With pump gas. Let me know your thoughts. I know that the 3.622 would be a good set up but definitely like the idea of a stroker.

 

I am 9.98-1, just run good fuel and or meth injection if you run decent boost.

 

I am 10.5 on 10 psi with 4” stroke

 

I have a 10.2 motor I built to take ~16psi, 4" stroke. 0 miles on it however

You will probably appreciate the 4" stroke torque, but you might have to pull the motor out for a refresh more often than if you stayed 3.622

 

What block are you starting off with?
if a 6l block i would go with the 3.622 in a daily. The stroke wrecks havoc on the piston skirts and bore.

 

Well I ended up going with a 4” stroke crank from scat with a set of H beam 6.125” rods and a set of CP pistons with -13cc dish, 3.799 bore. I should be sitting around a 9.3 compression ratio. It started as a 4.8L block. But with the stroke and over bore it will be at 362.7 cubic inches. Truck really isn’t a daily any more it’s more of just a weekend and odd day threw the week driver.

I had talked to the guys at scat about the position skirt thing and they claim to have not had any problems with wear issues so I will be curious to see what the outcome is.

How much meh are you guys running?

 

I always heard strokers consume lots of oil but my buddies 408 in his daily Denali has close to 20 or 25k on it and loses less than half a quart between 5k oil changes. My LQ4 with 3.622 stroke uses considerably more. I think my next engine build will be a forged 4.8 stroker like you just made.

 

My stroker is on full when I change the oil. My stock 5.3 burned considerably more oil between changes.

 

My 408 burns 0 oil as well!

Also 0 gas. But hey, who's counting right?!

 

just wait for the new 6.6 gas engine’s crank