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2ndMDRebel
03-13-2006, 01:26 PM
We talked about it at the track and I wanted to expand on it here. What I was wondering was if it is feasible to increase the boost on my supercharger to say 14psi so that it would effectively build more boost lower in the rpm range and have a mechanical valve to bleed off the pressure over 9psi which is considered "safe" for a stock block. I know the MAF would have to be moved from in front of the s/c to after the s/c and bleeder valve and a new SCT tune installed. Other than those things is something like this doable?

Disclaimer: Not trying to start a "s/c war" thread, just looking for some more mid-upper rpm oomph.
MarauderMark
03-13-2006, 01:33 PM
I would talk to Dennis.:up:
Zack
03-13-2006, 01:34 PM
Upgrade to a JT-Trim or the new YSI from Vortech.
The YSI will act like a ROOTS.
rayjay
03-13-2006, 07:07 PM
Out of curiosity, how much boost is safe with compression ratios not designed for forced induction?
MikesMerc
03-13-2006, 07:32 PM
That depends on the fuel used, and the tune. It also depends on the presence of inter cooling and its effectiveness.

That said, I see many "street" application non inter cooled in the 6psi to 8psi range, and "street" kits in the 6psi to 12psi range for the quality inter cooled kits. I've seen solid 10:1 compression 4.6 mod motors running 14psi all day long. But, they do this with a safe tune and higher octane gas..
thePunisher
03-14-2006, 03:21 PM
the ysi is a standard rotation blower.. so it will not work on the modulars. the jt is the reverse rotation version of the ys-trim....very similar. and those blowers are not responsive down low like the s-trim and smaller blowers are. youve got to spin them a bit more to get the low end boost response out of them...very similar to a large turbo. they are really oriented for race applications where rpms reach the sky a bit more. not even close to the responsivness of a roots blower....you probably wouldnt be happy with those blowers in a street application.
MarauderMark
03-14-2006, 05:28 PM
Upgrade to a JT-Trim or the new YSI from Vortech.
The YSI will act like a ROOTS.
Maybe its time again for an upgrade.:up:
Warpath
03-14-2006, 05:55 PM
We talked about it at the track and I wanted to expand on it here. What I was wondering was if it is feasible to increase the boost on my supercharger to say 14psi so that it would effectively build more boost lower in the rpm range and have a mechanical valve to bleed off the pressure over 9psi which is considered "safe" for a stock block. I know the MAF would have to be moved from in front of the s/c to after the s/c and bleeder valve and a new SCT tune installed. Other than those things is something like this doable?

Disclaimer: Not trying to start a "s/c war" thread, just looking for some more mid-upper rpm oomph.

You'd be wasting a lot of power pumping 14psi and only using 9 psi.
thePunisher
03-14-2006, 06:12 PM
upgrading to a bigger blower will not accomplish what he wants...it would do just the opposite. if you want the low end boost response then stay with the s-trim and pully it up......or get the trilogy...
Joe Walsh
03-14-2006, 10:10 PM
You'd be wasting a lot of power pumping 14psi and only using 9 psi.

Ah-HAH.....That's one thing I hadn't considered.
Tom (2ndMDRebel) and I were talking about this at the track and I thought that this could be done.
If you used a blow-through system, you could just dump excess boost via a blow-off valve.
You would only be wasting power above the rpm point were you are making 9+ psi boost.
I've been thinking about a centrifugal S/C pullied for 14 psi to build boost earlier, BUT limited to 10-11 psi at the top end.
I don't know, am I missing something here?
Oh Hell! I'll just run 14 psi and be done with it!:burn: