autoonero

I'm currently doing a 62 resto and I was wondering if I could get some suggestions on what manual trans. to use. I'll be putting in a LS6 with it.
Any help would be greatly appreciated.
Thanks,
Larry

rick piras

I assume you're referring to a "modern" LS6, not an older big block version. A Tremec TKO-600 5-speed will fit behind an LS motor and usually not require any trans tunnel modifications. A T-56 will definitely require tunnel mods. If your floor has sagged over the years even the TKO-600 will be snug, or extremely snug. You'll need to get the motor to sit down as low as possible at the front in order to have good driveshaft alignment.
The TKO-600 is a close-ratio 4 speed with overdrive, you can select either a .82 or .64 overdrive ratio. If you want a deeper first gear you could go with the TKO-500 version. In a lightweight car like a mid-year I don't think that's necessary, but some people prefer that.
I'm running an LS6 with the TKO-600 (.64 overdrive) and it's a great combo.

Good luck,
Rick

ILBMF

I hear a lot about TKO's not shifting well at high revs. Never did drive with one, but I've heard that lots over the years.

warrenmj

Never had this problem with mine in almost 10 years.

R66

Old SCHOOL,
I have a Doug Nash 5 speed that I ran in a Vega drag car that has a 327:1 1st gear. If you are not wanting to change the gears in the rear end, and are happy with your highway milage, the DN 5 speed (Now Richmond) will give you the performance of a low gear with the durability of an M22 or Super T10 and the durability of a higher gear with a larger pinion.

The only problems are the crossmember has to be modified and the driveshaft shortened with a TH400 input and HD U-joints. I broke everything except the Nash on 11 flat second runs.

If you go to the overdrive transmission, you have to match up the differential gears to best utilize the overdrive and obtain off of the line performance. Do your math on the 1st gear and differential ratios and tire diameter before you enter into the money trap.

I would love to have the Nash in R66 or our 68RS, but don't want to go to the hassle at our age.The M20 and 3.36:1 gears are perfect for crusing when you have bad knees and back. The Nash is still under the bench.

R66

Rick, What is your rear gear?? You need to help the man out with the final gear ratio. He has to calculate it for his application - drag strip or interstate driving.
Sound good if you don't have to modify anything.

rick piras

Sorry, I should've mentioned what my gears are on the initial answer.
I'm running 3.73 gears in my current chassis, with 245-45-18 tires. IIRC, they're about 25.7" diameter. I had similar diameter tires when I had the stock chassis/rear end, which was 3.50. Just my opinion, but I think with rear end gearing in the 3.5 to 3.90 range the deeper 3.27 first gear in the TKO-500 is a little too deep for such light cars as C2's. The shallower first gear with the 600 tranny (I think it's 2.87) works really well for quick acceleration off the line to carry good speed into the 2nd gear shift.
I have the .62 OD, with the gearing and tire diameter I have now the engine is turning about 2200 RPM's at 65 MPH, and 2500 at 80 according to my GPS.
Hope this helps,
Rick

C2 Hot Cam Guy

No problems w mine

R66

I'm the sorry one, I asked you and didn't give the info myself. I kinda felt your suggestion was superior to mine as I only ran the DNE 5 spd in a street / strip car with a 411:1 gear and 28" tall slicks and street tires. The milage was about 6 mpg and the RPMs at highway speeds were well over 3,000. But, it was fun back in the day.

Your info is everything he should consider, low gear, high gear, rear gear, and tire diameter to determine what he wants for his application. Gross weight of the car also.

Thanks for helping him.

OHSIXX

I have C2, LS3, with GForce 5-Speed. Tranny is very loud. Would the TKO 600 be a significant upgrade?