Squealing pulley (?) after Paxton S/C install

[Billy Coons]

Just got my car back from the shop after a Paxton S/C install. Car ran ultra quiet (albight the normal supercharger whistle) for about 15 minutes...then like turning on a switch, a high-pitched squeal from what appears to be a pulley or a belt (haven't used a hose yet to isolate exact location) occured.

Noise re-occurs at about 15 minutes after a cold start-up and gets progressively louder as time passes. No noticable degradation in performance (like from belt slippage). I also notice that whenever a load is placed on the car (acceleration) the noise decreases/disappears. When idling or compression decelerating, the noise gets louder.

I'm leaning toward the idler pulley until I check the noise location with a hose. Anyone else experience this? I see alot of past threads on aftermarket pulley's and I'll go this route if it turns out to be a failing pulley. DLM seems to be the name used for the pulley's a lot. Any others?

 

[MikeR]

After about 3k miles my tensioner pulley on supercharger came loose. I had same type of noise. Same occurances as you have. I looked and noticed the supercharger belt around tensioner pulley and the pulley looked like it was twisting out sideways. I compared with buddies and mine wasnt right.

I tightened the bolt for it from under car with a open end wrench. It was pretty loose. After doing that the noise is gone.

 

[VIPER R]

Check your alternator pulley nut. May not be tight.

 

[MacManInfi]

Mine came from Paxton loose. :O It was pre-installed on the arm, but loose.

 

[ILLSMOQ]

Mine came from Paxton loose. :O It was pre-installed on the arm, but loose.

It comes pre-installed...but evidently they are prone to coming loose....mine has not come loose but I now know to check it.

 

[mjorgensen Woodhouse]

They are not tight from Paxton and need to be checked each time they are installed. The same goes for things like the fittings on the auxiliary fuel pumps. Things this important should all be nut and bolted before running them.

 

[MacManInfi]

Thanks for the additional input. Great to hear from someone who knows their stuff.

 

[Billy Coons]

So after all was said and done, turned out all pulleys were tight, but the stock serpentine belt needed replacement....with only 10k original miles on it!

New one is in now (not a perpendcular groove cut type) for $45 and no more noise! Go figure. Didn't think Id have to replace it with such low milage...especially when it didn't squeal before the install.

 

[Fast Too]

Billy - Why are your dyno numbers low? You should be up around 650rwhp

 

[Billy Coons]

Not sure, have to send my puter back to DC Performance for another tune. Running a bit rich down below 3500 rpms. Maybe because when we dynod her she was warmed up and the temp was 98 degrees? Also, I'm using the FMU setup and not a dedicated system.

 

[Fast Too]

With the basic out of the box Paxton kit, you should be at or very near 650rwhp. Does the tuner your dynoing at know how to tune your split second box?

 

[Billy Coons]

Actually, the shop here just dynos the car, I'm sending the dyno sheet numbers and the computer back to DC Performance for another tune.

 

[Fast Too]

Could be wrong but I don't think you need another reflash. You need to tune the SS Box at this point.

 

[Billy Coons]

Well she's running rich low, and DC told me to ship it back. The shop here doesn't tune Vipers so do you know someone near me that can do it?

 

[Fast Too]

The reason it is running rich, and this is speculation on my part, is that the second fuel pump kicks on at 3,000 rpm and your fuel and timing maps need adjusted through the SS Box. If you have the SS Box software there is a shop in Winchester VA (AR Fabrication) that can tune it. They tuned mine and did a good job, albeit I have a VEC 3 and not an SS Box. They should be able to tune the SS box though but you would need to provide them the software.

 

[Billy Coons]

OK, gotcha. Don't have the software, nor does the dyno shop here. They all recommended I upgrade the fuel system like you did for that extra power, the added cost just isn't in my budget for the time being. Think I'll fine tune what I have the best that I can for now...

 

[Fast Too]

OK, gotcha. Don't have the software, nor does the dyno shop here. They all recommended I upgrade the fuel system like you did for that extra power, the added cost just isn't in my budget for the time being. Think I'll fine tune what I have the best that I can for now...

Gotcha, good luck, a bit rich A/F is safe so you should be fine

 

[doug fresh]

i would call Doug Levin, you might be able to send him your split second box for him to put his tune in it. I ended up sendind him my car because eveybody near me had problems tuning it. Local shops by me said they could do it "no problem". Doug worked out all the bugs and now car runs like a ***** ape. Atleast call him, He is a great guy and will always talk to you even if he didn't install it for you.
Doug Levin 954-434-9356

 

[Bobpantax]

Hi Billy. What kind of dynamometer did the local shop use? If they used a Mustang dynamometer, your numbers are perfect. If this is the case, multiplying your numbers by 1.1 gives the equivalent rear wheel Dynojet dynamometer numbers. In your case, 660 rwhp/ 583 rwtq which would be right on the money.

 

[Billy Coons]

Doug, you feel my numbers are way off also?

 

[Billy Coons]

Hi, it's a Dyno Dynamics Dynamometer, made in Australia. DC said it was a good system.

Hi Billy. What kind of dynometer did the local shop use? If they used a Mustang dynometer, your numbers are perfect. If this is the case, multiplying your numbers by 1.1 gives the equivalent rear wheel Dynojet dynometer numbers. In your case, 660 rwhp/ 583 rwtq which would be right on the money.

 

[Bobpantax]

Hi Billy. I am sure it is a good system but does it operate like a Mustang dynamometer or a Dynojet system? If it operates like a Mustang system, your numbers are fine.

 

[Billy Coons]

Not sure actually... Here's their link:

Dyno Dynamics - Home

Any idea?

Hi Billy. I am sure it is a good system but does it operate like a Mustang dynamometer or a Dynojet system? If it operates like a Mustang system, your numbers are fine.

 

[Bobpantax]

I did some research in the past few minutes. What I found indicates that the Dyno Dynamics Dynamometer produces a true load based dyno plot, unlike a Dynojet and similar to a Mustang Dynamometer. Your numbers are fine. Breathe a sigh of relief and enjoy your car.

Best,

Bob

 

[Billy Coons]

Well, that's about the best darn news I heard today! Thanks!

 

[Bobpantax]

You are welcome. You might want to change your signature numbers to 660/583 so someone doesn't ask again.

 

[Billy Coons]

Not a bad idea!

You are welcome. You might want to change your signature numbers to 660/583 so someone doesn't ask again.

 

[pteam]

Billy,

Go to another local dyno and get it dyno'd somewhere else for comparison.

 

[Fast Too]

Billy,

Go to another local dyno and get it dyno'd somewhere else for comparison.

plus 1, that would give you real peace of mind. You mentioned you were rich, what was the A/F on the dyno graph you have?

 

[Billy Coons]

Readings were taken after the hi-flo cats and Corsa:

14.7-14.9 with no boost applied at any rpms

At WOT:

10.0 from 1700-2700 rpms (0 - 1.5 lbs of bst)

10.2 steadily increasing to 11.0 from 2700 - 3100 rpms (1.6 - 2.3 lbs of bst)

10.7 - 11.2 (avg) 3100 - 4800 rpms (2.4 - 4.5 lbs of bst)

11.3 -12.9 steadily increasing from 4900-6000 rpms (4.6 to 8.0 lbs of bst)