I'll be getting an ATI P600 model Sunday, but have already been considering selling it and spending some of that money on nitrous. I've heard quite a few people say if you can't afford a rebuild then don't go with boost. But after reading through all of the literature I received from ProCharger I'm feeling pretty confident that my internally stock motor should be alright with 8 lbs. My next worry is that my car is an A4 and I'm afraid that I'll be tearing my tranny or rear out with boost. I know that with Nitrous you can use pills to set the on off points so that your not shifting while the nitrous is being sprayed. How exactly does this work with boost?

Also, can I run less boost (thinking 6lbs.) with the P600? Or should 8lbs. be fine like ATI claims?

 

I believe ATI claims 8 psi with their intercooled kits, and 5-6 on their non-intercooled kits. It shouldn't be any harder on your tranny and rearend than a nitrous kit would be. As long as you program the car so it's generous with fuel and keep your boost low, you shouldn't need to do a rebuild for a while. I've got ~30K on my stock bottom end. The only thing that I broke was a head gasket due to a fueling problem. But I like the way the cam sounds and how hard the car pulls now.

 

You can get some good miles out of the stock motor but the odds are against you. You have to moniter everything, all the time. Make sure you have a boost gauge, fuel pressure gauge, scanmaster and possibly some other data logging software before you get into boost. Bump the timing down and keep it rich. All it takes is one time and....POP.

All of ATIs kits are intercooled and I believe the smallest pulley they make is 8#s. But there are many other places to get pulleys if you want to run less boost.

 

I thought I wouldn't have issues with my 6# Vortech kit...I keep the timing retarded 1.5 degrees unless I was running 100 octate, 24# SVO injectors and still took out my ring lands after 17K miles. Nitrous will be easier on the engine as it is used less often than a blower...the blower is there everytime you put your foot into it. The blower also adds heat into the cylinders which permotes premature detination. If you want power on demand, go the blower route and plan for the rebuild. If you only want better track times, go nitrous.

 

I have a boost gauge, digital FP gauge and a Scanmaster.

Also, where is the best place to get a BOV and 6lb. pulley from? The kit is intercooled, but I'd still like to run less boost. Thanks guys.

 

So how exactly does a blower work with the shift points on an automatic?

 

It's really hard to compare nitrous and a blower as power adders. They are most useful for different purposes. Nitrous is very hard to use to any decent effect on the street, it's too hard to control wheelspin. But in terms of improvement on the track/dollar it can't be beat. Depends what you are after. I think they really can complement each other, that's why I use both. But that is a high dollar route, for sure.

As far as a blower and engine longevity, for a number of reasons a stock LT1 is just not very tolerant of boost. Basically, the pistons combined with the high CR are just not suitable. Very low boost with retarded ignition and a rich mixture can give acceptable reliability, but the performance gain is pretty modest with that kind of a setup.

Rich Krause

 

With a P600B on a stock motor, you'll be seeing pressure around 3200rpm.

I ran mine for right around 3 years running an MSD 6BTM set @ 1.5*/# of boost. I also ran the car a little richer than normal to be safe. Over the years, I would back the fuel down a little here and there and the car responded. If you don't get greedy (I turned my retard down to 0.5 to race a GSXR600 and popped the motor) and keep a good eye on the fuel pressure, you can run for a while on a healthy stock motor. Notice I said.."a while". My motor was pretty wore out for a 5x,xxx mile motor when it finally blew.

Since the blower is belt-driven, everything is based off engine RPM. On a shift (whether manual or auto), the pressure built up inside the tubing is released via a bypass valve. This prevents the air from being forced against the throttle blades (bad) or reversing flow and crashing into the impeller on the charger (very bad).

 

You answered your own question

Marc