1994 TA with a Powerdyne needs help.

[Mighty Thor]

I got an e-mail from this gentle about Powerdyne. I thought I go ahead and post it here since there's quite a few of us running with the Powerdyne and we could better help him. Here's his e-mail to me:

I am slightly puzzled, however, by the way I always hear people saying how P/D blowers make boost real! low in the powerband, basically right off idle.

This is not at all the case w/my setup. I normally do not see any boost under 5000 rpms, unless I am in a taller gear on the highway and mash the throttle.

My car is a 6-speed and I am running the 6psi pulley. I see around 5 psi max. boost w/this pulley, which I am told is right around normal.

I won’t see that however, until right before hitting my preset 6000 rpm rev limiter in the MSD 6AL. I have 7 degrees of timing pulled out of the PCM at WOT along w/larger fuel injectors, and a boost-referencing adjustable fuel pressure regulator in lieu of the P/D FMU.

The only reason I can see for the boost coming on only in the upper rpm ranges, is due to belt-slippage. As you probably already know, slippage is very common w/centrifugal S/C’ers. But I have gotten the belt as tight as I feel it should be to prevent bearing damage in the head unit, combined w/using “Insta-Boost” belt treatment on the drive belt to further comba! t the slippage issue.

Is their any other reason you can think! of that would cause my blower to not make low-end boost? Additionaly, is your Firebird a V-6 car?

What kind of power do you think you might be putting to the rear wheels? What method/tools did you use to tighten your blower drive belt? Thanks for your help, and if you do actually read this and have a chance to answer these questions, please email me back at billp@artesyncp.com. Thanks again, and take care.

Bill P.

[Mighty Thor]

Chances are your car is indeed experiencing major slippage. It was a common thing for us as well, but we've remedy that with the use of a different belt route and the use of a grooved pulley (we run ours at the flat side of the belt).

Yes, belt slippage is a common problem for centrifugal. But once that's fix, it makes good power. I've seen an PD LT1 set up before but I don't remember how the belt tensioner works on it.

We did found out that Dayco or Gator belts works better than Gates belt. You might want to try that and see how it works out.

As far as tightening it. Tighten it till there is only an inch of play to it.

I've also seen a Vortech Saleen owner put a 6 lateral "V" groove to his 9 psi pulley. This might also help. But have an extra pulley with you just in case it doesn't.

Boost coming on at idle is true for positive displacement blowers like roots and twin screw. They make great power at the bottom end but fall short at the top end. Centrifugal is more for high range top end. So you are under vacuum most of the time. But when you nail it boost will come on and depending on the size of pulley you have, it can come on at 2200 rpm or 3500 rpm and all the way up.

This is where I'm getting my Water/Alcohol injection www.coolingmist.com I ordered the stage one kit. There's also a better one but pricey www.smcenterprises.com

[ July 25, 2005, 01:17 PM: Message edited by: Mighty Thor ]

[jessica2112]

My boost comes on at 3,500. I pretty much remedied my belt slippage issue. I am hoping that the 2.8 pully helps my boost come on a little lower in the RPM range, but I have no idea if it will. If not, at least I will be running a little more boost. Thor, is your kit installed yet? Just curious how it is working out. Intrested in getting one.

[Mighty Thor]

Jessica, I probably get to it till sometime next month or Sept. Right now I just I'm getting leather seats and will be installing it. I'm putting my '98 cloth seats to the '89. Plus I still have work on my truck. I will definately let you know how it works out.