TREMEC T56 Magnum S197 Transmission

[AutoXRacer]

Gerald, give me a good reason you'll need two OD gears, lol.

The idea behind a 6 speed (and even better a 7 one) is to usually have a 1st that helps the car move, and a tall 6th to work as an OD and keep the inner gears closer. With closer ratio trans as yours, it has been designed to do exactly that, 5th is actually closer to 4th as usual and a tall 6th to be the sole OD. As these transmissions derive from older designs, they keep a 1:1 fourth and a close 5th. Newer design usually makes the 5th closer to 1:1 (MT-82s are actually 1:1) and then an OD.

With a 3.55 to 3.73 you would barely felt the difference. As I told you, 3.90 might be the sweet spot depending on your tire height, use your car as it is and you'll enjoy it. Wait until you can get on it, gear after gear and how these close ratio makes the car shift like a motorcycle.

It does!!!! While driving through the city, below highway speeds, I found myself shifting!! Previously I kept it in two gears...now I am actually using all the gears!!

I have only partial-WOTed it twice, but both times I did find that I had to shift sooner and faster...like a motorcycle.

Previously, I had to wait to get through the gears...now I am not fast enough to keep up with the shifting. LOL

But traction is my biggest worry now!!! I mean its crazy fast (acceleration)!!!
As soon as you step on it, everything becomes a blur while trying to modulate the throttle to reduce wheel spin... Its a handful now!!!

I'm a little scared of it...yes, its that wild!!! I need to tame this bitch!!! LMAO

 

[BruceH]

Give it a few days. You may start wishing you went with 4.30 or 4.56.

 

[cruisin]

So I went with the 2.97 first and have 3.73 in the back.
To make it as close to what I had before, should I jump up to 4.10s?

I'll be swapping them a few times I am sure.
I will need to go down to 3.55 I think for doing mile races.

I would like the highest gear that can get over 200 in 5th.

 

[BruceH]

So I went with the 2.97 first and have 3.73 in the back.
To make it as close to what I had before, should I jump up to 4.10s?

I'll be swapping them a few times I am sure.
I will need to go down to 3.55 I think for doing mile races.

I would like the highest gear that can get over 200 in 5th.

Here's a nice calculator that will let you input 3 different rear gear ratios to compare.

http://www.wallaceracing.com/gear-speed.php

 

[AutoXRacer]

So I went with the 2.97 first and have 3.73 in the back.
To make it as close to what I had before, should I jump up to 4.10s?

I'll be swapping them a few times I am sure.
I will need to go down to 3.55 I think for doing mile races.

I would like the highest gear that can get over 200 in 5th.

The 2.97 version will go 184 MPH in 5th with 3.73 gears and 26.7" tires.
With 3.55 gears it will reach 193 MPH.
You would need 3.31s to go 207 MPH in 5th...but it will take you forever with that gear ratio...total super over-drive!! You will need 1000HP or more!!

Problem is, how are you going to break into the 180s with a S197 body?

 

[AutoXRacer]

Give it a few days. You may start wishing you went with 4.30 or 4.56.

Actually I just opened her up in 3rd gear and no wheel spin in sunny 68 degree weather!!!

So it is promising!! I'm sure the heat soaked motor (less power) had something to do with it.

Maybe the 4.10s aren't that bad... LOL
I need more seat time...

 

[cruisin]

The 2.97 version will go 184 MPH in 5th with 3.73 gears and 26.7" tires.
With 3.55 gears it will reach 193 MPH.
You would need 3.31s to go 207 MPH in 5th...but it will take you forever with that gear ratio...total super over-drive!! You will need 1000HP or more!!

Problem is, how are you going to break into the 180s with a S197 body?

I guess I could always shift to 6. I'll have to play with it a bit.
As for the horsepower, it's not a concern, that is covered.
I have seen cars with less than 900 go over 205, I'm just trying to take a shift out of the equation. I'll play with tire sizes though.
Thank you. I think 3.31 would be too low.

 

[cruisin]

Here's a nice calculator that will let you input 3 different rear gear ratios to compare.

http://www.wallaceracing.com/gear-speed.php

Awesome. Thanks. That makes calculations a little quicker than my pencil and paper.

 

[69Mach1-409]

Ok, finally got a decent 2 hr drive in of slow, stop-n-go back roads. 1st - 4th gears from 1,400 rpms - 1,800 rpms sounds like a someone shaking a can full of rocks.. I can be accelerating easy, hard, or just maintaining speed and it's noisy as hell. Once I get into 5th or 6th it's quiet as can be.

Is this normal? ..could it be the McLeod clutch?

 

[Saleen304]

The McLeod clutch has been known to have some floater disk rattle in that rpm range. Maybe not as high as 1800 though. I had some in my current car and it got better (didnt disappear) after about 1000 miles. Is this your first twin disc clutch?

 

[69Mach1-409]

Yup, first twin disk.

If it's normal, then I'll just try to drive around it. It just had me alittle worried cause I don't recall hearing that noise until last night. You can't feel it, just hear it.

 

[Wicked97]

Yup, first twin disk.

If it's normal, then I'll just try to drive around it. It just had me alittle worried cause I don't recall hearing that noise until last night. You can't feel it, just hear it.

Yea you will notice a little noise and those real low RPMs with the car loaded.

You get it to break in some more and it will quite down some.

 

[AutoXRacer]

Ok, finally got a decent 2 hr drive in of slow, stop-n-go back roads. 1st - 4th gears from 1,400 rpms - 1,800 rpms sounds like a someone shaking a can full of rocks.. I can be accelerating easy, hard, or just maintaining speed and it's noisy as hell. Once I get into 5th or 6th it's quiet as can be.

Is this normal? ..could it be the McLeod clutch?

Yep, its normal unfortunately...

Mine does the same from 1,500-2,000 RPM. Gets worst with light weight flywheels and aluminum/carbon driveshafts. The heavier your drivetrain, the quieter.

It doesn't really get quieter in my opinion. The only thing I have recently found that quiets it down are 4.10 gears. Must be due to the drivetrain seeing less load. It was really bad/loud with my 3.55 gears. I hated it; totally avoided that RPM range.

Now with the 4.10s its still there, but doesn't seem to come up as frequently and not as loud.

I had the same noise with my TR3650 too... Got really aweful with an aluminum flywheel and aluminum driveshaft. I reverted back to stock driveshaft because it was so loud and annoying (when I had the TR3650).

 

[HG6283]

I didn't read through the whole thread, but has anyone figured out how to get 5th to work with cruise control, 4th and 6th work just fine, but 5th is that extra gear in the middle.
Is there a fix for that?

I have that issue with my TR6060. Never found a cure

 

[69Mach1-409]

Thanks guys. Maybe that gear change will happen even sooner now. HAHA!



HG6283 - My cruise works with 5th and 6th. Something in your tune maybe?

 

[skwerl]

I hate lugging my car down at low RPM. Even in normal street traffic I shift around 3000-4000 and rarely drive with the engine at less than 2000 rpm unless I'm coasting toward a stop. Maybe I'm just addicted to the instant throttle response of stepping on the skinny pedal and getting pushed back in my seat. If you're cruising along at 1300 rpm and want to accelerate, it takes some time or a downshift before you can do anything.

 

[69Mach1-409]

I'm not lugging the car.

Cruising around my little farm town I don't want to be pulling 3k-4k rpms, so I drop her into 4th going around 35 mph. I'm just maintaining speed, pulling 19-20psi vacumm.. so it's not under any real load at all. You can barely hear the exhaust yet the trans is making alot of noise.

 

[BruceH]

I'm not lugging the car.

Cruising around my little farm town I don't want to be pulling 3k-4k rpms, so I drop her into 4th going around 35 mph. I'm just maintaining speed, pulling 19-20psi vacumm.. so it's not under any real load at all. You can barely hear the exhaust yet the trans is making alot of noise.

Like the others have said a twin disk floater will rattle. Mine has been very specific at around 1700 rpms in 4th gear. This is with a 10 spline RST/3650 and the current 26 spline RST/6060. The 6060 is alot quieter than the 3650 but that 4th gear 1700 rpm rattle is still there. After a little while you will subconciously adjust to put yourself out of the rattle zone.

 

[screaming_pc]

Just turn the radio up or drive faster.

 

[69Mach1-409]

Haha!