Just wondering if this is what compressor surge sounds like...

Was towing a 7000 lb (+/-) camper trailer at around 62 mph.. when I would have to go up hills the boost would go up to 18 lbs and I would hear this strange sound... it sounds like when you use a bandsaw to cut a piece of wood, but it's not as loud... hard to explain.

It was only doing it when I was towing. unloaded it doesn't make the noise. EGT's touched 1100* a couple times, but were usually between 900-1000* The elevation was 4,500-5,000 feet.

Maybe the turbine blades were hitting the inside of the housing when they got superhot? I dunno, but I surely hope it's not that... or if that is even possible.

 

Very high whine? But no grinding sounds? If that is what you are hearing, it is normal! Not if you build boost and let off really quick and hear a huffing noise, that is turbo bark.

Is the pyro pre or post turbo? If pre, those numbers are normal. If post add 2-300 *'s. If u hit 1300-1400 for a long time..... I would worry and back out of it. I would keep my foot in it if I saw those numbers. THe number to worry about is 1400*'s IMHO.

Jon

 

If you like that sound and want to hear more of it, install a BHAF. You will think you riding in a big truck.

 

The pyro is now pre turbo reading off cylinders 4-6.

 

bump...

Still makes this noise when boost hits ~22 psi. Either towing or unloaded. Obviously it does it more when towing...

Very faint high pitched noise, kinda like a meat saw cutting bone or something... I dunno

I'm going to start saving up for a better transmission, just so I can really add some power and have peace of mind.

 

Have you looked at the boot for your intercooler? Do any look oily, sweaty? Maybe you have a boot that is leaking.

HTH
Glenn

 

Well I will be installing coolertubz soon, so I will check it out. It seems to build a normal amount of boost though.

 

Our trucks are not like the Ford's and should not have any oil in the cooler tubes. If you have oil it is coming from a turbo seal. On the Ford's the crank case breather is plumbed into the air intake so they get oil mist that builds up.

 

When I have heard it, it sounds like a balloon, when you stretch the neck while letting the air out. That's an air leak around a boot, or possibly where the elbow is on the compressor outlet, as there is an O-ring there.

Chris

 

You still have the stock H1C compressor?

I don't think you would get surge at 18-20 psi with an auto.

What were your rpm's?

If it was a boost leak wouldn't his EGT be over 1100*?

 

The turbo is still stock, it produces 22-23 psi right now. I have no real fuel mods done yet. The full power screw is in all the way, but I have one of those pumps where you have to weld on an extension. I have the DennyT fuel pin waiting when I get back from out of town.

I honestly don't think it's the turbo, or intercooler boots.

 

Nah, he doesn't have that big a leak. If it was leaking that bad the sound would be a woosh, not a squeal. I had a stock 98 once that squealed because the rubber boot, deteriorated from the oil on it, had begun to separate inside. In that case he did loose most of his boost, but in this case I suspect it's a clamp that isn't holding the pressure meaning a clamp is not tight enough for the additional boost. Stock is what, 18 psi? As old as the boots are though, it could be the additional boost has found a weak spot in one of them and it is separating.

Chris