Humm... Thanks everyone for your input.

I think I should clarify a couple of things...

1- The Vac/Boost Gauge line is tapped into the post intercooler port on my DFIC. I'm going to try putting it on the pre intercooler side to see if that changes anything. I heard the DFIC can cause a drop of -1 to -1.5 psi?

2- The whooshing sound is intermittent, not continuous, and only under WOT at upper RPMs.

Also, the car definetly felt stronger when I first installed the 19%, call it adaptation if you will, but I dont think so, it was revving ULTRA fast through the RPM's before, and now, it seems not to climb as fast through the RPM's, like there is some sort of restriction. Oh ya, and I had an issue with my initial pulley install. I didn't put the hub all the way on to the shaft, but i installed the pulley anyways. Took about 10 miles before the belt started to walk off the pulley and lost one rib before I made it home crawling, scratching my head about the noises coming from under the hood. But those 10 miles were incredible, boost was instant and the zing sound was MUCH quicker. That was the NAPA belt that came with my ALTA 19%. I then uninstalled the pulley, realized my mistake, flushed up the hub with the end of the shaft, reinstalled the pulley, and this time put on a Gatorback belt. The idle and low rpm noise of the gatorback are awesome, like there's a real blower under there now, but it doesn't sound so zingy anymore??? Could all this be a slipping belt? There were 2 sizes suggested on here for the 19% and the Gatorback, and I got the larger one so I could install easier. What does a slipping belt on our cars sound like?

Car only has 18k miles, still under warranty, but I dont see myself taking it in for this sort of thing. I'd expect to get laughed at when they popped my hood and saw everything.

 

If you do a search on this forum there are some suggested sizes, pully - belt.
Cant say what a slipping belt would sound like on an SC but it should squeel..

 

Please share the part numbers for both the NAPA and Gatorback belts used.

The Gatorback 537 will work without slipping as long as there is no belt contamination. The NAPA 535 (by Gates not the cheap version) works without slipping also and provides a little more tension (although reduced belt wrap) than the Gatorback 537. I have 25,000 miles on my 19% with both belts and no problems. The NAPA appears to run hotter as evident by glazing sooner but it doesn’t seem to affect performance.

For loss of zing, look for leaks.

 

only cos i perfectly agreed with every other part. Just to clarify, to what part of k-huevo's post were you saying "not really"?

I agree that 15psi is way too low for a 19% pulley. WOT in 2nd gear at 7000 rpm (or even 6000rpm for that matter), he should be pulling at least 17psi above atm pressure

--edit: just read jymontoya's last post. Your belt may be slipping, get a shorter Gatorback and retest

 

Not to disagree with k-huevo since I think he is 1 of the most knowledgeable contributers on this forum but at 8k on this car & another at 12k ( we went to Mini the same day to order the new 03 "S" ) the cats failed. The wrap dislodged from the can on both cars. The symptoms were some loss of power & some inability to reach rpms above 5200. There was loss of boost because there was enough vacuum present to prevent the BVP from closing fully. At the time it was common to do a VGS mod on some SC vehicles, 1 of these was a friends Lightning. Tried it, just got stranger. Bad gas, vacuum lines, SC boots & everything else we could look for was looked at or replaced. The header was replaced, 2k later, by the dealer & the car came back to life. Since I'v seen this, I assumed this was a known issue. Guess not.

 

Thanks again everyone!

The first belt I used was the one that came with my Alta pulley... a Napa 060536

After i messed up that one with my stupidity of not putting the hub all the way on the shaft, I installed a 4060537 Gatorback.

I really dont think it's slipping, and it also has no problem what so ever with accellerating to redline. My only problems were the noise coming from behind me, which I'm thinking more and more is the fuel pump...

And the reason for the lower boost seen. i'm going to experiment with a couple of things this weekend/week. I'll first try changing to the pre intercooler bung and make sure all my teflon tape has things sealed properly, which I didn't do the first time.

Then, I'm going to experiment with a HAI since i have a couple of filters that will work. Supposedly that can raise boost pressure?

I just want to set off the damn SES light for overboost! hehe!

 

etalj, evidently Steve did not read through my post or there would have been no disagreement “all things being equal before the intake port and at the same rpm”, the BPV is located before the intake port.

 

I read the post. "all things being equal before the intake port at the same rpm" was well taken, no argument at all. If anything that statment says it all.
The only part of your post that I had issue with was "Eric Rowland got it right".The Post: "Wouldn't exhaust restriction be seen as MORE boost? Less power, but more boost, as the engine has relatively less throughput" This reads as a question with a sugestion as the answer. How you could conclude that "all things being equal before the intake port" had any intent in the post & state, "got it right".... Not realy, is a good answer.

 

jymontoya, please post if you get more boost.

No, I don't think your belt is slipping either.

Have you tried the boost gauge on the inlet side of the IC yet? There may be some useful info, at least a possible place to look.
Have a great New Year,
Steve

 

With all my mods the best I've seen is 13.6psi but at WOT it pulls like crazy.

 

Sorry to hijack but why dose a strong boost set off the DSC light? I've learned to start off a bit slower in 1st just to keep the wheels from spinning but it seems to happen alot in 2nd and sometimes in 3rd and I don't heel the wheels slipping then.

 

235 wide tires help a lot.

Also, I think that most of us turn off the DSC before we really get into it.