Looking For Your $0.02

[Chevythunder17]

Can we further this dialog as I have already purchased the Pro ATI D-1SC kit with all of the tuner package (pumps,injectors...blah..blah). I really liked the fact that the ProCharger was a stand alone unit (no plumbing of oil lines). I live at 3800 ft elevation and this unit will make 8lbs of boost so with my elevation correction it should be at 6.5lbs. Now it is not a daily driver as I only take it out for cruises with the family (ice cream/burger go getter- sometimes in that order) but I do like to go heavy at the 1/4 track on Friday nights (legal street drags). Brakes and suspension/torque arms/315/35/R17 on a Moser 12 bolt 3.73/4.10 (both sets in the garage) have been all done with some basic mods to the engine (160 thermo, 1.85 roller ratio, MAF and full SLP exhaust mods). I still want to hear the pro's/cons of each so that I can be aware of all the potential pitfalls of the systems themselves.

Your grateful Grasshopper!

Pros of the Procharger would be that you already have it. The systems do work very well, especially since it's intercooled unlike the Vortech systems which are not. You sounds like you have the proper supporting mods. The belt can sometimes come back to bite you at higher boost pressures, but I don't think 6.5 psi is going to cause you any grief. Keep in mind that there are ways to make the system more efficient such as lowering the compression ratio (317 heads are great for that), changing the cam, etc.

How many miles on the engine? Do a compression check on all eight cylinders with the engine warm. If you find that there is a big variance or it's low across the board a rebuild might be a good precursor to going with boost.

What fuel system components did you get?

What transmission are you running? A 4L60E you might want a bit of a stall and a nice sized transcooler. In an M6 you're going to want to upgrade your clutch and possibly the slave cylinder depending on the year (01 and up have a better master and slave).

In regards to turbos, the setups are somewhat more complicated. My honest opinion is you NEED an intercooler with a turbo. Bad enough that you get heat from compressing air, but you are doing it with 1300+ degree air. to boot You don't need headers with a good turbo kit, the plumbing will be of a good quality, ideally the kit would be complete. Out of all the aftermarket turbo companies out there, there is one that I recommend to anyone (PM me; I don't believe they are a sponsor) especially because they have been around forever and their systems make great power. I have seen easily a half dozen turbo companies come and go. They all seem to make power, but something happens along the way and they fold up.

Also keep in mind that centrifugal superchargers DO NOT get power instantly. It takes engine RPM to make boost; the curves are proportionally linked unlike turbocharging. The only superchargers that have instant boost are root styles, like Magnason, Kenne Bell, Whipple, but none of those are directly made for F-bodies due to the cowl. There is one company that does make them to fit F-bodies, but the kits are $6500.

Does a turbo have to be properly sized? Yes, but that is dependant on many factors including where you want your powerband to be. Smaller turbos will generally mean the boost comes up sooner but peaks far earlier than something larger (say a 60-1 vs. a T-76). You need to be realistic in how you plan on driving the car. If you think you are going to bring it to the track once a year, build it to be a great street car (read: smaller turbo). It's not about peak power, it's going to be about your torque curve. Bigger torque curves are going to make the car more fun from light to light.

Just some random thoughts...

[secondgearscratch]

he has to have a manual. does anyone run a 4:10 in an a4?

[Chevythunder17]

Lots of guys do. They like the way the car launches better.

[LS2Tuner]

he has to have a manual. does anyone run a 4:10 in an a4?

With anything that has a power adder you don't need a gear that deep. Your making soo much more tq now it et's better with a 3.42 than 3.91's.
Same thing with our nitrous cars they like less gear.

Unless you running a 29 inch tall tire I would stay with mid 3's if it's going to have boost.

[Chevythunder17]

With anything that has a power adder you don't need a gear that deep. Your making soo much more tq now it et's better with a 3.42 than 3.91's.
Same thing with our nitrous cars they like less gear.

Unless you running a 29 inch tall tire I would stay with mid 3's if it's going to have boost.

With a supercharger you want to have more gear to spin up the blower, and I don't think he is really worried about running out of MPH (I don't see him caging the car). Nitrous cars make lots of torque, you can get away with less gear. Turbos prefer numerically lower gears to load the engine more.

[LS2Tuner]

With a supercharger you want to have more gear to spin up the blower, and I don't think he is really worried about running out of MPH (I don't see him caging the car). Nitrous cars make lots of torque, you can get away with less gear. Turbos prefer numerically lower gears to load the engine more.

Sorry we tune the our blower cars with pulley changes to change the speed. Your adding a great deal of tq with the super charger also so we pull gear. Doing 120 ft burnouts was cool in high school now I'm into dragging the back bumper. MPH has nothing to do with what I'm talking about. The trap speed should be there due to the power adder. I'm saying it'll blow the tires off with that much gear. O'h maybe not if your running 5-6 lbs of boost. But we never run that large of a pulley combo to do a small boost like that.

[Chevythunder17]

With a numercially lower gear (ie 3.23, 3.42) you are never going to build the RPM to make the power; it's basically going to bog the engine. Is a 4.10 a bit much, yes. I'd go with a 3.73, but no lower. If you do the suspension up right it shouldn't be doing 120 ft long burnouts.

[SSmaro]

I currently have 4:10's in my A4, shifting at 7k rpms. Works fine for me, but I am chainging to more boost and will step down to 6500rpm shifting points, so 3:73 are going in to the car in a few days.

[Chevythunder17]

What are your mods?

[SSmaro]

What are your mods?

Forged 355
Victor Jr modified heads2.08/1.65 70cc chambers
custom cam
race built 4L60E w/ 3k stall

10 Bolt w/ Auburn pro series posi/4.10's/stud girdle,etc-Borrowed Time!!

ATI D1SC 8-rib- not sure how much boost right now, new pulley setup...maybe 12-14#

Car ran 11.70-11.80's at 8000ft DA before w/4.10's and 4-5# boost.

[Chevythunder17]

You don't have a boost gauge? Ballsy...

Sounds like a pretty mean setup. What are you crossing the traps at MPH/RPMwise?

[LS2Tuner]

I currently have 4:10's in my A4, shifting at 7k rpms. Works fine for me, but I am chainging to more boost and will step down to 6500rpm shifting points, so 3:73 are going in to the car in a few days.

So your going through the traps in OD.......? If not what tire are you running?
Also curious as to what cam your running with that powerband?