Just for a reference for you guys, I pushed the head gasket once at 15 psi and 24* of timing with half pump/half race fuel. I'm also running 706 casting heads and ARP bolts, not studs.


You should be able to get 18 psi to work, just be very safe on the tune up. I don't have to rely on my truck to work everyday so thats why I don't feel bad about experimenting with the tuneup on the edge.

Give us some details about your motor (size, cam, intake, heads, exhaust, rpm range, compression, Stock crank pulley diameter?) and we can give you a better guess on what pulley will best suit you.

 

Finally came to me: Joe at leftcoast32 for the HD tensioner.

Blown06 : specs are in my sig. exhaust is pacesetters 3'' true duals w/X pipe large case Magnaflows. cr est.9.0 ,stock crank pulley, redline 6800 shift 6500

 

I got my tensioner from Joe too. Its a very stout piece, and a very simple bolt on upgrade.

If your making 18 psi with a 3.5 and you wanna get down to around 12 psi, I would say a 4" pulley is about what you need. My motor is a little smaller than yours and I was hitting 14 psi with a 4" at 7000 rpm. That 4" will be nicer to your belts as well. Should be a solid combo.

 

What is this tensioner? I don't see it on the web site.

 

call or email. he's going to want pictures of your belt setup too.