Greetings fellow Whipple fans. A year and a half ago I installed a used Whipple charger to my 1997 GMC K1500 Suburban with the 5.7L Vortec. Absolutely LOVE the performance and sound this supercharger brings. My question is, would I gain any more performance or sound by adding a cold air intake? I am currently running a K&N filter in the stock air box.

Thanks,
Scott

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Anything that helps get more air into the compressor will increase power.
Your options are somewhat limited for cold air with this kit because the crossover duct is set up for the factory filter box and MAF location. Also keep in mind that it's important to be feeding the coolest possible air to the supercharger because compressing it just adds more heat and the PCM will pull timing when it sees this, as intended. (That's why the IAT sensor gets relocated to the intake elbow.) Many so-called "cold air intake" kits draw air from the engine bay. Most definitely do NOT want that with this system. The air in the fender well is pushed in from the grill area, you can see this if you remove the passenger side market light look in there. It's not too bad really. The plastic elbow between the filter and the MAF is somewhat restrictive. It's designed with smooth flow over the MAF in mind, not performance. Not much that can really be done about that without changing the air box.

There another thing worth diverting some attention to. Between the throttle body and the compressor is an aluminum elbow with a relief cast into it to clear the brake booster vacuum check valve fitting. If you look inside the throttle body it's easy to see that this portion of the cast is like a wall to some of the incoming air. It's possible to remove this elbow from the compressor, cut this section out, and weld on a much thinner piece of aluminum in the gap. This modification is worth some horsepower.

Your kit came with a 3" pulley. If you have a freed-up exhaust and headers, regap the plugs to 0.40", and can make sure you have a 160-degree thermostat, order up a 2.7/8" 6-rib compressor pulley for it. (Might need to replace the belt with one 1/2" smaller with a pulley change. If you find this is necessary use a Dayco PolyCog belt - nothing else will both have traction AND hold up with this system.)

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"James B." '99LT_Tahoe4Dr2WD, Tuned L29 Vortec 454, 62#Injectors, Cutouts, 4L80-E 10.5"14bolt ,EatonPosi-4.56:1, Gear_Vendors, HydroBoost, (NEXT: Brodix heads, 230/240 cam, SS roller rockers, longtubes, THEN: Intercooled W200R-8psi in the future...)

Thanks James for the information. I am running the NGK TR6 plugs gapped at .040" and I also have the 160 degree thermostat. I am also running an MSD Boost Timing Master so I can run 87 octane when I am not towing. I also removed the restriction on the throttle plate. I did not know about the casting restriction. Thanks for that infor.

As far as tuning goes, I have Jet's DS Tuner software, but, I'm not sure what parameters to change to increase performance. Do you have any suggestions? The truck runs really good now. Is there any more power to gain through tuning? What about a "boost a pump"? I am running about 65-75 PSI fuel pressure with the stock pump.

Thanks again for your help,
Scott

Any thoughts on parameter changes to go with the Whipple on a vortec 5.7? I have Jet DST tuning software. Any help is appreciated.