TREMEC T56 Magnum S197 Transmission

[BruceH]

Eric I didn't see this before, but is there any reason why this is the case? Would a fidanza not work?

This RST was used with a Fidanza flywheel. It still held power but had a slight catch on the lip from the mismatch. This came out with the 3650. When my 6060 went in I used a McLeod flywheel with a new 26 spline RST and it covered all of the clutch surface.

 

[cruisin]

I went with the 297 and 355 rear but think I will be switching to 373s. I use 6th on the highway when cruising on long drives. It will save you gas but you haven't given enough info. For drag I would say go with the 297 I didn't look at your sig for the mods.

 

[skwerl]

If you're lugging the engine too low while cruising at high speeds you will actually use more fuel than if you downshift and let the engine lope along comfortably at 1800rpm. Lugging a high strung V8 down to 1400rpm at 70mph isn't efficient.

 

[cruisin]

You just need to find the sweet spots when cruising.

 

[jodadejss06gt]

I have the 2.66 1st gear with 3.55. I'll admit 1st gear is too tall for racing. I'm still going to see what it will do. I may eventually switch, but we shall see. I still put mine in 6th gear at just over 60, while it may lug a little when going up hill it isn't bad on flat level ground.

I wonder how some vettes get 20+ mpg with a 7.0 and cruising on the interstate at 1300rpm??? My mpgs went up a little with this trans over my other one. It def isn't the best combination, but it works for now.

 

[69Mach1-409]

I have the 2.66 with 3.55's and wish I'd of went with the 2.97. My car is getting the 3.55's replaced with 4.10's at JPC as we speak.

 

[jodadejss06gt]

Let me know how that works out for you when you get it back. I was thinking 4.10 or 3.73 would be a good choice. I have tall rear tires too so that doesn't help much either.

 

[69Mach1-409]

Let me know how that works out for you when you get it back. I was thinking 4.10 or 3.73 would be a good choice. I have tall rear tires too so that doesn't help much either.

Yeah, I have 305/40-18's, so they're not helping matters much.

 

[jodadejss06gt]

Yeah, I have 305/40-18's, so they're not helping matters much.

315/35/20's here lol

 

[69Mach1-409]

Ouch!

 

[Bingo]

Anyone had issues with cruise control randomly disengaging? I wouldn't think it would have anything to do with the transmission, but it started doing it right after the install...

 

[HG6283]

Anyone had issues with cruise control randomly disengaging? I wouldn't think it would have anything to do with the transmission, but it started doing it right after the install...

Not randomly disengaging, but since I had the TR6060 installed the cruise never worked at all in 5th gear.
In 4th gear and 6th gear, cruise works fine.

No one can tell me why.

Probably not a related condition to your issue, but you never know....

.

 

[jodadejss06gt]

Mine cuts out from time to time too

 

[skwerl]

Can't say as I ever used cruise control in the 3.5 years I owned the Bullitt. Tried it once to see if it worked but that's it.

 

[Saleen304]

Cruise cuts out on me. Seems to happen in 6th mostly after I hit a bump...

 

[Bingo]

Cruise cuts out on me. Seems to happen in 6th mostly after I hit a bump...

Same...usually while going down a hill, it seems. I'm flummoxed.

 

[AutoXRacer]

Happens to me too...

One question for all you guys... At what RPM does your cruise disengage?

I have a theory that its due to too low RPMs and it automatically disengages.
When I used to use cruise with my TR3650, it was always above 2,000 RPM.

With my T-56M, its right at 2,000 or below and I experience the disengagement...its a PITA.

 

[Bingo]

I was cruising around 70 MPH @ 1600 RPM (3.55s with the .50 6th is sweet). I don't think it's related to engine speed, as I've done some slow cruising with both the 3650 and the T-56. I can go hours without cruise cutting out, but then there's times where it'll cut out multiple times within a matter of minutes.

I wonder if because it rolls so well in 6th that the car overspeeds downhills and the computer doesn't like that, so it just shuts off. But then again, I've exceeded my set speed and it has stayed on. It seems completely arbitrary, though like Saleen304 said, maybe going over bumps has something to do with it.

 

[AutoXRacer]

Weird, mine has always cut out below 2,000 rpm.

So what is it? The only thing the computer sees from the transmission is the speed sensor.

I am thinking the computer is set to the old TR3650 and the new T56M screws up the limits set for the TR3650.

I think its RPM vs Speed thats triggering the cruise to shut down.

 

[danzcool]

I think its RPM vs Speed thats triggering the cruise to shut down.

That's where my money would be, and it would explain why 5th doesn't allow cruise at all, since it's smack dab in between the tr3650's 4th (1.0) and 5th (.68)
Has anyone had the cruise cut out while in 4th? I'm guessing 6th is close enough to the stock 5th that it works most of the time since they probably designed it with some slop so you run without having to retune if the tires were a different height.