Hello.
Does someone here know how much boost you will get with the different pulleys (3.33, 3.12 and 2.87) on the V2 Si on a stock engine?

 

stock exhaust? stock cats?

boost is just a measure of air not getting into the engine, so anything can totally change boost pressures.


ive seen people get 9 to 22psi on the 2,87

 

Well, my engine is not stock. I was just wondering how much boost a bone stock engine would be at.
My engine has:
-Cosworth intake with a 75mm Throttle body.
-HR headers with race cats, dual 2.5" exhaust into a single 3" system.
-Stock cams and light ported heads.
-Fully buildt bottom end with Eagle rods and Wiseco 11.0:1 pistons.

I know its kind of stupid to ask about boost because every engine is different but I was just trying to get idea on where I will land

 

Also different crank pulley makes a big different. I have 3.33 on my si and with the 6.78 crank it makes 20psi at 8k

 

I have stock size crank pulley

 

ya so, 8-22psi are all numbers i have seen on stock block VQ's with a 2.87 pulley.

 

If you have seen 8-22 psi difference in boost the engine mods must be different. Thats why im asking about the pressure on a unmodified engine.