josh99ta

iTrader: (1)

Supercharged 6-speed vs. turbocharged A4 auto setup, that is the question.

Purpose of the car: Daily driven street car, sees very limited drag strip and autocross duty, mainly WOT pulls on the street not racing just for personal enjoyment.

Intentions of the car: To have the most fun street car possible with my given platform.

Background: I have a friend who owns a shop that is helping me collect parts for a 6-speed swap on the GTO. Last I heard it's a go, but all the parts haven't been acquired yet. If I go ahead with the trans swap, I'll be doing a D1SC Procharger down the road or possibly a 122HH Magnacharger. If the acquisition of parts falls through or if my mind is changed I'll stay with the auto trans, build it, and go with a turbo setup (single front mount TC76, which should have no lag with my stall). No mixing and matching, these are the only two combos on the table. I like superchargers and banging gears, and turbos and autos go together like peanut butter and jelly. These are the only two options on the table.

Goals of the car: 550-600rwhp, 125+ mph traps, daily driveable and reliable as the day is long.

Both setups should be able to easily reach my power goals staying in the single digits for boost levels, so at the end of the day it comes down to power delivery/power curve, level of control/driver involvement, reliability, etc. Currently my buddy is still sourcing parts for me and the trans swap is a go, but I'm completely open-minded to other setups if they fit my goals better.

I've never owned a forced induction car, but have ridden in a number of them and had friends who have owned different setups, which is why I've settled on one of these two combos. For those with long-term experience with either setup, regardless of power level, what were your thoughts on the overall setup? Pros and cons? Why should I go one way over the other?

Thanks in advance for any input. It's a big decision on the future of the car and since I have no personal long-term experience with FI I'm all ears for any input.

omore001

iTrader: (1)

Unless you are getting an extremely good deal on the 6-speed swap and/or a really good deal on the supercharger kit, I would build the Auto and go with the turbo kit. It will be faster/better on gas/ and have excellent street manners (I'm very aware supercharged cars can also yield excellent street manners). I've owned both a 6 speed supercharged v8 ('04 Cobra) and a turbo automatic LS1. For the street and the strip I enjoyed the the turbo auto LS1 way more for multiple reasons (comfort, better fuel economy, faster, more power). If you really need to bang through the gears, get the manual, if you want comfort, consistency, and the performance edge, build your auto and turbo it.

josh99ta

iTrader: (1)

I am getting a good deal on the swap. No worries there.

The SC setup will cost more, especially factoring in the M6 swap, but I'll get to bang gears.

The TC setup will cost less by a few thousand bucks, but I worry about trans life (don't trust A4 transmissions to hold up to abuse for any extended period of time).

Better fuel economy with the turbo setup and auto trans? I get ~17mpg the way I drive the car now. With the 6-speed swap that would be ~24mpg. Turbo might pick that up some in the auto, and s/c might bring it down a little in the manual setup, but I would think the s/c manual setup would still get better fuel economy.

I see pros and cons to both on the surface, it's those issues that you run into in the long run that I don't know about having never owned a FI car.

Thank you for your input. It's good to hear someone enjoyed the turbo auto setup more especially comparing it to an 04 Cobra. Obviously with the 6-speed you can roll into it on the street and modulate the power better, what was your experience on the street with the turbo auto and just being able to stab and hang on? I don't want to be blowing the tires off all over the place, which I see as a benefit to the 6-speed setup being able to roll into it.

c0ncEpT

iTrader: (4)

If you want to have fun go with the 6 speed swap and the Procharger. If you want to be fast go with the converter and the turbo.

I wish my car was a 6 speed all the time just for the shear fun factor of banging gears and what not.

30th t/a

iTrader: (51)

My car was a 6speed but after seeing everyones awesome results with a auto & a turbo setup i wanted to give it a try and Im glad i did. Its hard to beat a turbo auto setup.The auto will give better ETs at the track and the turbo will still give you insane topend pull.
I would build the crap out of your auto and TC that bitch!

Silver_TransAm

iTrader: (2)

I agree with the above. Turbo really pulls on the top end with the auto, and you can stay in the power longer.

Silver_TransAm

iTrader: (2)

Definetly build the trans up or even go with a 4l80e. I went through 3 60e's before my 80e. I personally would not push a 60e past 500rwp.

Photochop

iTrader: (74)

First off, keep the auto. A clutch will die just as soon as a 4l60e will. Spend the money on a good A4 build, or go with the 6 speed and a mccloud twin disc or stage 4 spec if you really wanna bang gears.

I think you'd have the best luck with a D1SC kit setup from EPP, or an APS twins setup if you want to go turbo. Both are straight up to do, should be fairly headache free, and will be VERY reliable. They also provide 'room to grow on' if you decide you want to make more power in the future.

Have your tranny built/buy a built one, get a matched converter and call it good.

Tricked-Out-Toy

iTrader: (4)

I say six speed single TC-76 and call it a day itll meet every goal and then some.

K99Raptor

iTrader: (2)

josh99ta posting under K99Raptor's account...

I know that's what you'd say Tater. And after more thought I'm seriously considering it.

Silver TransAm, can you explain what you mean by staying in it longer? Obviously going WOT into OD in an A4 is asking for trans failure, so that means I'm limited to ~130mph before I run out of gear. With the M6 I don't have that problem. I'd be aerodynamically limited before being gear limited I'd imagine.

30th t/a

iTrader: (51)

the Auto will keep the turbo in boost through out WOT. With a 6speed, every time you shift, your boost drops and it has to spool again. I didnt care for the way my last TT setup felt with the 6 speed either.

hellbents10

iTrader: (10)

Not if you shift with a one step and your right foot stays to the floor the whole time.

omore001

iTrader: (1)

I'd like to see your technique in practice against an equally modified and equally powered turbo stalled automatic. I'd put my money on you falling back a few lengths after each of your "power-shifts".

99Z28LS1

iTrader: (4)

this is no"power shift" he does shift in that manner, but with the 1 step, he'll keep his boost while shifting if im correct

Tricked-Out-Toy

iTrader: (4)

Josh isnt looking for "a few tenths" he wants something that is fun to drive, has plenty of power, reliable, adjustable, and can meet the demands of road course/autoX , DDing and strip with the majority being DDing. Banging gears takes the fun factor cake any day of the week.

Photochop

iTrader: (74)

Have the best of both worlds and go with a RMVB 4L80E

josh99ta

iTrader: (1)

Truth. I just don't know if I'll be able to get all the parts for the swap though, or the shop sourcing my parts I should say. Right now everything looks like a go and we should have everything, but there is just as good a chance of us not being able to and it all falling through. I'm supposed to go down this Wednesday and we're supposed to start on it. We'll either get the parts and it'll be a go, or we won't and it'll fall through. I won't have the time off work to pull the swap off again until next fall so if it doesn't happen now it'll be this time next year before I can do the trans swap...if I even want to at that point (I'd do turbo auto before then probably).

Also TOT is right, I don't care about a few tenths or being faster than the next guy at all. I don't care about ET or being faster than anyone. I just want the car to be the absolute most fun possible.

Silver_TransAm

iTrader: (2)

What I mean is there is no taking your foot off the gas and having to respool the turbo after every shift. Granted it wont be much, but when your messing around on the highway you can pull on a m6 every time he shifts. Ask me how I know.

It has also brought up the no lift shift stuff thats out now. Basically all it is, is a rev limiter activated to a preset rpm by a switch when you depress the clutch therefore keeping your turbo spooled up. The new cts-v has it as well as the new ss cobalts. Interesting to say the least, but have yet to see anybody do it in person.

In the end it is all preference. If I had my way I would do an m6 on an all motor setup and an auto on a turbo setup.

OH and I think I did blow my last 60e due to 6000rpms in 4th gear and 180mph, but it was fun. Hopefully my 80e will take it. You can overcome aerodynamics with enough power.

geeteego

iTrader: (1)

Josh, build the auto and go turbo.

You'll love it.

hellbents10

iTrader: (10)

I do it in person and yes can watch me the car looks like a auto when I do it. It just shoots a fireball out the tail pipe when it bangs the turbo on the shift lol. Its no slower to make the shift then Chris's turbo SS with torque management to keep the built 65 alive.

Dave's 6 speed GTO has no trouble with auto cars on the highway with his 6 speed.