pcar928fan

Mark,

Not really a fair comparison to other 928's since yours (even before the stroker) was putting MUCH more power to the ground that most! You were already quite a few HP (40? 60? 80?) above my GTS's... So, you may have more traction issues than someone who has not done a lot of engine work or been lucky enough to get a car that someone else has done said work to...

David L. Lutz

Hacker,

I just emailed you about your gearbox!

mark kibort

Well, that might be true, But my car put down the exact same numbers as Ron's GT. However, now my 5 liter part euro was like this and yes, it just didnt have the power as the holbert car. 290rwhp vs 320rwhp. not a huge difference, but still a differnce. Keep in mind, street tires lack all sorts of grip.
When i got the car it was 290rwhp. after headers, air box and general tune up things, it jumped to 335, falling back to 320ish for a bunch of years, until recently stablizing at 305rwhp. (bad knock sensor?)

mk

mark kibort

if you drive at 70mph and 2200rpm, you have a 2.2
especially if its a 5 speed and in the US.

mk

mark kibort

Hmmmm, i might be interested in that now.

mk

hacker-pschorr

Ok, I'll look for it

Lizard928

That is the swap I did on my car. Mainly because of the boost I will be running, and 1st was abit too short on the 2.75 box.

heinrich

Hilton ... trust me on this ... get a spare .. your car will be down longer than you expect ... As far as LSD is concerned, yes with a 5-speed LSD is mandatory .. in an auto I do not appreciate LSD. I have an LSD auto 2.2 sitting here (another S4) and I really would rather not have LSD under cornering for unexpected kickdowns....

heinrich

Which is why I think the 2.64 is a great compromise ... for my car.

Hilton

On the subject of changing final drive ratio - is it possible to replace the ring and pinion but keep the rest of the gearbox the same? Or were there significant internal differences that prevent it across model years and transmissions?

If so, has anyone ever tried switching a manual 5-speed with the 2.54 ring gear/pinion from an S4 auto box?

mark kibort

you would end up almost what the 2.72 has as far as net ratios. (with exception of 5th)

I dont know if all the rear ends are interchangable. (ring and pinion)

mk

Lizard928

Hey Heinrich,

Glad you are really enjoying the swapped tranny btw. :P

I just got informed the other night by my gf that you had msged me a few times. I have been out in the field for awhile now. I will be home soon and will be taking a month off.
I am interested in swapping autos with you, as I would rather have the LSD auto in my 87, mainly for when the snow flies if I drive it. Let me know if you are interested.

Jim bailey - 928 International

The automatic pinon shaft BOLTS to the back of a Merc auto ....the 5 speed pinion shaft goes through the transmission very ,very different.

Hilton

Thanks Jim

Was an academic question - I figured if I'm gonna have the whole thing apart I should make sure I've identified all the WYAIT's I might possibly want to do while I pull apart my 2.64-ratio'd 5-spd and dismantle the transmission to re-seal and LSD it.

PorKen

The 2.20 is dawdly at low rpms with the stock converter (must be worse with an S4's even larger TC), unless you dial in a fair amount of cam advance (4-6°), but then you take a hit on top end hp.

I luv my auto w/LSD. Totally different beasty than without, even on dry pavement. I'm able to use the awesome power of an '86.5 much more often.

If you have your Merc box adjusted properly, it won't downshift unless you want it to.