I have an A4, in my 94 Z and I have spent hours researching T56's and 4l60E's and such. Usually responses are dependant on the persons situation with their car; so I am asking about my particular situation.

An A4 to M6 swap.

My car has only 36k (stored every Ohio winter (Oct to April) and babied by a 52 year old since 94) so I'd like to keep it and therefore the swap. Car goes in for winters (so far) I have GMMG exhaust and plan on headers/CAI/gears this summer and cam/heads next summer. I only run street tires. I'll only have the money do a straight up swap one with someone who wants a 4l60e. Unless, of course, the tranny is cheaper than dirt, which it usually isnt.

The way I see it, to get my Stock 4l60e to handle a mid (xe 224/230) to large cam (cc306) I’ll need to invest about $800 in a TC and tranny cooler anyways, plus I enjoy driving manual more. I think that the 4l60e is rated under 385hp which is less than what I plan to put to the flywheel. The only reason I didn’t get a M6 to begin with was because I found this Z lightly used, no winter wear, and 28k for a good price.

I go to the track occasionally only to check how much my mods improve my time. I don’t care about drag ET's other than to show progress. I’ve gone once since I bought it in July 03. I do quite a bit of highway driving since my G/F lives in Cleveland about an hour and half away. I have heard that the M6 is easier on the engine and mileage b/c of the way it is geared.

I am thinking about doing a swap, and I have the resources to do it. Is it worth it and what are the pros and cons of these tranny's or the swap?? --Or personal opinions or stories on each. I want to compile as much information as possible before making a decision.

This is what I know so far, are these correct?

T56- stronger built
can handle more power unaltered
something to the tune of 400hp and 450ft/lbs, on the MN6
more dependable than Auto
good for stock 7.5" as long as you don’t launch hard.
better gas mileage b/c of extra O.D. gears,
almost bulletproof
easier on engine due to lower RPM operating ranges
more fun!

4l60e- better for launching and track purposes (doesn’t matter to me)
not as good gas mileage (assuming same rear gears and engine).
cant reliably support as much HP/TQ without race build or aftermarket TC and tranny cooler
not as reliable in general
not as strong (stock)
more problems involved.
(debatable) faster ET with TC and programming. (again don’t care)


--Can anyone give me a thorough opinion or evaluation? Any comments welcome.

Should I post this in Tranny tech? I figured general tech b/c of the upcoming mods and transmissions capabilities to handling these mods. I have searched it, but I want an evaluation of my particular situation.

Thanks

-Dustin-

 

IMO the manual tranny may and I say MAY be stronger, but the clutch on these machines suck. That's because of a couple of things. One is they operate backwards from other clutches. The fork is pulled instead of pushed. This leaves small room for a beefy clutch. Some pressure plate manufacturers make stiffer springs that easily over power the slave cylinder. Some try to fatten up the clutch plate and that leads to almost perpetual engagement. Still others use a material like Kevlar that "grabs" too hard or too quickly. Don't get me wrong, I like to row my own as much as any body, but when I reviewed written material about these clutch set ups, I changed my mind.

But back to your car. If it is as pristine as you say it is, it would be a shame to modify it. Keep it original, baby the thing and keep it protected and get you another beater. The car you got sounds like a rare find. Enjoy it the way it is.

BTW I've seen this discussion before and I know I'm gona take a flogging for my opinion. However I do not want to spend a lot of time under the car.

Dave