9:1 pistons and boost ?
Thread Starter
Launching!
Joined: Nov 2004
Posts: 243
Likes: 0
9:1 pistons and boost ? I recently got a 95 Z28 bored to a 355 with forged 9:1 pistons. It is a single turbo car with a Blitz intercooler. The fuel system consitst of a Racetronix in tank, in line Bosch 420 and 55 lb injectors. I read all over the place that 8 lbs of boost is the most you should run on these cars on a stock bottom end and with a REALLY good tune perhaps 10 lbs. My car is currently making about 500 RWHP at 9lbs of boost. How much more can the forged pistons allow? I have heard the stock rods and crank are quite strong and it is my understanding that its the pistons that are the weak point. If this is true it seems like I could perhaps add another few lbs of boost to the car. Any thoughts?
By the way, if I choose to upgrade from a 9 to 11 lbs spring, I will have the entire car re-tuned, dyno'd, etc.
Thanks.
By the way, if I choose to upgrade from a 9 to 11 lbs spring, I will have the entire car re-tuned, dyno'd, etc.
Thanks.
Depends on what pistons.. I would say a forged 9 to 1 piston would be fine in upwards of 14 pounds as long as you have fuel and the right plugs/ignition... I would be worried about the rods and bolts though.
Thread Starter
Launching!
Joined: Nov 2004
Posts: 243
Likes: 0
Originally Posted by My84Z
Depends on what pistons.. I would say a forged 9 to 1 piston would be fine in upwards of 14 pounds as long as you have fuel and the right plugs/ignition... I would be worried about the rods and bolts though.
-As long as your pistons are spec'd to take the power level you seek, you are okay there.
-I have friends who have done 600rwhp with stock rods and crank, and 9:1 slugs in LT1 engines.
-I think at 12psi (also depending on other factors) you might find the limits of pump gas. with your combo. If you have to scale the timing back bigtime to make pump gas work, you might be better off reducing the boost level and adding the timing back in. Inlet air temps of 100F would be fantastic, and inlet air temps over 150F become problematic.
-I have friends who have done 600rwhp with stock rods and crank, and 9:1 slugs in LT1 engines.
-I think at 12psi (also depending on other factors) you might find the limits of pump gas. with your combo. If you have to scale the timing back bigtime to make pump gas work, you might be better off reducing the boost level and adding the timing back in. Inlet air temps of 100F would be fantastic, and inlet air temps over 150F become problematic.
Thread Starter
Launching!
Joined: Nov 2004
Posts: 243
Likes: 0
Originally Posted by Pro Stock John
-As long as your pistons are spec'd to take the power level you seek, you are okay there.
-I have friends who have done 600rwhp with stock rods and crank, and 9:1 slugs in LT1 engines.
-I think at 12psi (also depending on other factors) you might find the limits of pump gas. with your combo. If you have to scale the timing back bigtime to make pump gas work, you might be better off reducing the boost level and adding the timing back in. Inlet air temps of 100F would be fantastic, and inlet air temps over 150F become problematic.
-I have friends who have done 600rwhp with stock rods and crank, and 9:1 slugs in LT1 engines.
-I think at 12psi (also depending on other factors) you might find the limits of pump gas. with your combo. If you have to scale the timing back bigtime to make pump gas work, you might be better off reducing the boost level and adding the timing back in. Inlet air temps of 100F would be fantastic, and inlet air temps over 150F become problematic.
Thanks for everyone for the reply's......any other thoughts?
