I have a 1989 S5 N/A bone stock with an automatic trans. It lags off the line but screams after 20mph. Before I begin I would like to remind you that I'm at 4700ft above sea level so the 1/4 times I mention will be bad. I'm running on the 4th as is and speculating high 16's and low 17's at best. My '81 stock could run 17 seconds so I'd imagine I can beat it. Now after I run I'm putting in a TII trany with a light steel flywheel. I'm also putting in a new intake kit and replacing my steel hood (heavy!) with the TII hood and doing a full tune up. (I mean everything!) So with a TII trans and roughly 100 pounds less wieght can I gain a second or more?

 

Just having a 5 speed will surely help once you learn to drive it well.

 

This is the only auto I've ever owned. All my other 7's were manuals. My driving could be better but its reasonable.

 

driving an auto, you have many hurdles to cross. first is different gearing and the loss of a 5th gear.

 

 

A swap is going to be alot of work and I need some assurance that it will be well worth it. I was lucky to snag a TII trans with everything. I'm going to get a custom driveshaft and everything should go fine. I'm going to run with the auto first to see what I gained after.

 

Why Do you need a Custom Driveshaft? if youre going to do the swap, and use a T2 tranny, you need to use T2 cylinders, T2 clutch assembly, and a T2 flywheel.
I believe you have the 4.1:1 rear end ratio. All the S5 verts came with that, even the automatics, unless you dont have a vert, then you have the 3.9:1 ratio, in which case I would recommend swapping out your rear end . If you want to get anywhere other than the grocery store, I would suggest doing the swap, I did mine, and it was very worth it, i must say. Although I would have done it myself If i knew how much it was going to cost, I got ripped off
edit* oh and i have an S5 T2 Viscious LSD for sale, its just the unit, not the complete rearend, but its only 160 shipped if you want it

 

Why did you want a TII trans? They are a bit heavier than the N/A tranny. You really won't need the added strength unless you go turbo.

 

Well to make your swap a hell of a lot easier get a NA tranny.

TII tranny will require you to do some modding.

You can get the Mazdatrix driveshaft which I have on my TII conversion.

OR you ca get the TII rearend.

With a lighter flywheel you will see a considerable slower time off the line. The rotational mass of the flywheel helps torque the car from a stop.

You will need to drop at a high RPM to get the same affects as a heavier FW.

Anyways. In the end a tranny swap will not improve your 1/4 time that much.

Headers,exhaust,coldintake,new tires,suspension,and possible pineapple sleeve will all better your times.

 

actually, i believe the 'verts and autos were the only ones with the 3.9s. n/as and turbos have 4.1s, and i believe all S4s had LSDs. autos are slightly heavier than their manual brother, too. so you have a heavier s5, heavier s5 with auto trans, and with the auto trans, you have the slush box.
good luck on your journey.

 

He should use a TurboII tranny because N/A tranny dies out faster then the motor does.

 

50 shot of Nitrous should help you out.

 

Tranny is fine on my 88 SE. The engine blew at 155k while the tranny is good.
88 GTU Engine blew at 102k while tranny is still good.............