94 Suburban

Wouldn't that be the other way around? A single turn of the wheel will result in many turns of the drive shaft.

supercharger.

Duuhh

homer

by far the easiest way is to look in the glove box at the "G" RPO code... if it's a GT4 it's 3.73, GU6 is 3.42

-Bret

ThanX, I have the 3.73's. I am trying figure out why with a whipple supercharger my Suburban still does have the pickup I think it should have.

The 94 suburban 4wd has a 5.7 with a whipple 3.73 gears--should be about

360HP

my 96 c1500 2wd pickup has a 5.0 with 4.10 gears--should be about 240HP

the truck feels like it has almost twice the power of the suburan. yes I know weight and gearing make a difference. but its almost 100hp more in the suburban. Is there somthing else I should consider? Both vehicles have 22" wheels so that shouldn't be factored in. The Suburban goes to the DYNO shop next wednwsday to see if it is even making the HP I was told it should get.

Did you upgrade the entire fuel system and the exhaust when you put on the supercharger?

The fuel system was upgraded when the whipple got put on back in 94. I am wondering if thats what the problem could be myself.

maybe the turbo is worn..

Do you have a boost gage?

Could be increased clearance between the lobes on the rotors. Not uncommon with a blower. That and scoring of the case are the reason they lose boost. The whipple used Teflon seal lips I believe. Plus Teflon coating on the lobes

There should be repair parts for them. snipped-for-privacy@whipplesuperchargers.com should get you the answers to that.

Yep as Steve W. said in his post, there is no "Turbo Up" or any other "rebuilder in a can" for superchargers... You say it was installed in '94 .. I wonder what the recommended TBO (time before overhaul) is on that Whipple unit.. It's a normal thing for the sucker to wear out.

Actually, I'd say that 10 years of traffic driving is a pretty good lifespan... The only other experience I've had with turbos/superchargers has been on diesel engines... They definitely have a maximum TBO or parts start damaging other expensive parts. This is on engines that run at a constant speed whenever they are running (effectively WOT) (saw a turbine for a Caterpillar 3608 that cost taxpayers $21,000... 2700hp @ 900 rpm w/ 30 psi of boost!)

I visited a CAT dealer in AZ on a service call. They were refitting a SCUD missile launcher brought back from Iraq (one of 2 they were working on). Shitty 12 cylinder Russian diesel was a nightmare, made a Lombardhini look intelligently designed. The army paid 250,000 a piece for the the two V8 units to replace them (3 something, don't remember the exact model), plus about 1 million in engineering and installation. They were something in the 600-800 hp range.

Back to the topic: If you can get a boost gauge, do so. You might want to loosen the exhaust up near the manifold and take it for a short run and see if there was an exhaust restriction. Could be something as simple as a plugged muffler.

sounds like maybe a 3508? search for that and see if it looks similar..

This is a good point. My boss worked on an Audi quattro turbo... it had a

5-cylinder gas engine with a nice fat turbo on it. He told me to take it for a drive one day because the owner was complaining about no power when he would step on it hard.. The boss only took it out for a leisurely drive. I took it out and put the pedal down... no go. Put it up on the lift and removed the cat. VROOOOOOM. Got a new cat.... I didn't get to drive the thing afterward (much to my disappointment), but the boss said the car was "scary". (Of course, he did have cataracts)

It sounds like a new fuel filter, new cat, and a clean K&N air filter could make a big difference. Maybe even a new O2 sensor. Should I make these changes before taking to a performance shop and haveing them put it on a DYNO to find out whats wrong. DAMN computer controlled crap. If it weren't for emissions I would just put a ZZ4 with a wipple on it in the suburban.

The filters are cheap and easy enough. A good muffler shop can check for a clogged CAT and/or muffler.