I'm currently running a ported LSA Blower with ported 5.3l Heads and custom BTR cam. I currently have a 2.45 upper Pulley and the truck is making 10 PSI with the stock lower. I want to raise the boost to 15psi. Does anyone know what size lower Pulley I would to achieve these.

Thanks

 

This site has a good pulley combo list:
https://weaponxmotorsports.myshopify...s/news/6826132

To technically reach about 15 psi, you'd need something like a 8.60 or 8.70 lower.

You probably wont be seeing 15 psi on your gauge since you have ported blower / heads, but you probably knew that heh, boost is tricky that way

Hopefully that helps! Cheers

 

Thanks. Looks like I'll be going to a 8.6 crank Pulley

 

Are you running a single belt setup?

 

Factory drive, OWK makes a kit allowing you to use the factory drive

 

What does the cam look like?

You can't fit that large of a lower ring on a factory drive set up... itll hit your water pump. The LSA guys get away with is because they are direct drive.

 

You are correct. Do you have a solution to this problem without changing the whole drive system.

 

Changing the drive setup is the solution if you use that blower. It’s just not the solution you wanna hear.

 

A 10% OD balancer. You will get another couple PSI out of it.

ATI sells them if you want to spend decent coin on a nice one.

Any word on what that cam looks like?

 

ATI makes the best hands down IMO. 10% OD like Rob mentioned should give you another 2-2.5psi, they are 8.25”