So I bought this Roush Performance Focus (yeah, yeah...they made one for the SEMA show a couple years ago, and now it's mine) which came with a Jackson Racing supercharger kit as part of the package.
My problem is, I'm only seeing 2-3 lbs of boost (they advertise 5 #'s). Could it be the belt, or do I need to recal the blow-off? I know some guys cut grooves across their pulleys to reduce slip. Might this work (with a new belt of course).
I plan on throwing a smaller pulley on it, so if that belt is slipping now, it may slip more then.

Thanks!

most jrsc see about 4-4.5psi near 7 grand. rarely do they see the full 5lbs as advertised. also, the gauge is sometimes off.

ps: if your adding a 2.3" or 2.6" pulley...why would it slip?...you would have to change the belt anyway.

Congrats on the car and welcome to Focus Fanatics

you may need to adjust your bypass valve. ive heard people w/ the JRSC that had to adjust the bypass to get it up to the 4.5 to 5 psi.

When you add parts like free flowing intakes and exhausts you will lose pressure. Why, because boost is only a measurement of back pressure. If you use an intake, race header and cat back you will likely see a decrease in boost.

Originally posted by Kicknzx3
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ps: if your adding a 2.3" or 2.6" pulley...why would it slip?...you would have to change the belt anyway.

I'm just concerned that the smaller diameter gives you less belt wrap both angularly and surface contact wise.

Some guys here at work said they think the vacuum routings may be incorrect. I'll look into that. I'm also looking into the bypass. I may have to play with that too.

I don't have any other engine mods like exhaust or anything, so it's not that.

Thanks for all your help!!!! I love this car! It's alot more fun to drive than I thought it would be![:)~]