Are you running a Tremec TKO-500, TKO-600, or T-56?

[nokones]

My TKO600 shifts very well and smooth. The shifting through the gate is very positive just like the old Hurst Competition Plus shifters used to be. My TKO tranny has the Sidewinder II shifter and I haven't had a miss- shift yet going from 2nd to 3rd. I am using the recommended GM Synchromesh Tranny Oil.

Oh, by the way, I scrapped the Tilton clutch assembly. I went with the McLeod Twin-Disk and Aluminum Flywheel setup, and I am a lot happier.

[gator68428]

I went with the TKO600 with synchro upgrade from Liberty. Standard overdrive (not road race option). At the time I went with it b/c cheaper, a little lighter and less hassle for bellhousing and tunnel, and met the gearing needs I laid out.

Now I see why 6 gears would be ideal though. For an all around package for a streetable, weekend autoX, road course and occasional trips to the drag strip, having a good overdrive to cruise at 80+ under 2500rpm and around at least 10:1 first gear (first gear ratio multiplied by rear end) are the min requirements, which the TKO600 meets. But as described next, I can see the logic behind an intermediate gear between 4th and 5th (but as i say I'm not missing it that much b/c I really have no biz going much over 130 and overall shouldn't affect my lap times that much)
If you watch my youtube vid on the track shifting from 4th to 5th (at 42s into the vid) at 130 mph (6k rpm) I shift slower (and lose a few mph) because for whatever reason it feels risky to the tranny to upshift to 5th quickly and its a tall gear so accel rate is slower after shift. But I still upshift on the straight to at least maintain 130mph (and i do gradually hit 135) and give the engine a break from the high rpm (just an old pontiac). I'm very happy with the TKO600 because I have no business getting too much over 130 anyways but can appreciate why the T-56 exists.

Here are the calcs that went into my tranny, gears and driveshaft selection. Tire diameter was measured by rolling the car on the ground 3 revolutions and meas distance on the ground to get an accurate number vs what TireRack says. Even though i have no business going over 130mph I did a sizeable safety factor driveshaft critical speed to almost 190 mph, just because... and you never know... maybe one day I'll push the 160 mark with more power and a roll cage on a big enough track (but likely would need a T-56 in that case to get there :-P )

[all4sho]

i went with a tko600, it was a great deal that i could not pass up and i wanted a 5 speed real bad

[Later-A-body]

I originally chose the TKO/6OO. I was happy to have the OD in 5th gear for the freeway driving but never liked the big spread from 4th to 5th gear even with 3.73 gears. It was hard to drive the car in 5th other than on the freeway. I also was not a fan of the 2-3 shift as well, and felt the numerically lower 1st and 2nd gear ratios would work better with my combination. When I decided to take the car apart again, the first thing I did was sell the 5-speed, and purchased the T-56 Magnum 2.66/.063 version. Now I can use 5th gear (.080) around town without the big drop in RPM and then 6th for the freeway cruising. The tunnel was already fabricated so that wasn't a factor.

[Shawn01754]

I went with the TKO600 with synchro upgrade from Liberty. Standard overdrive (not road race option). At the time I went with it b/c cheaper, a little lighter and less hassle for bellhousing and tunnel, and met the gearing needs I laid out.

Now I see why 6 gears would be ideal though. For an all around package for a streetable, weekend autoX, road course and occasional trips to the drag strip, having a good overdrive to cruise at 80+ under 2500rpm and around at least 10:1 first gear (first gear ratio multiplied by rear end) are the min requirements, which the TKO600 meets. But as described next, I can see the logic behind an intermediate gear between 4th and 5th (but as i say I'm not missing it that much b/c I really have no biz going much over 130 and overall shouldn't affect my lap times that much)
If you watch my youtube vid on the track shifting from 4th to 5th (at 42s into the vid) at 130 mph (6k rpm) I shift slower (and lose a few mph) because for whatever reason it feels risky to the tranny to upshift to 5th quickly and its a tall gear so accel rate is slower after shift. But I still upshift on the straight to at least maintain 130mph (and i do gradually hit 135) and give the engine a break from the high rpm (just an old pontiac). I'm very happy with the TKO600 because I have no business getting too much over 130 anyways but can appreciate why the T-56 exists.

Here are the calcs that went into my tranny, gears and driveshaft selection. Tire diameter was measured by rolling the car on the ground 3 revolutions and meas distance on the ground to get an accurate number vs what TireRack says. Even though i have no business going over 130mph I did a sizeable safety factor driveshaft critical speed to almost 190 mph, just because... and you never know... maybe one day I'll push the 160 mark with more power and a roll cage on a big enough track (but likely would need a T-56 in that case to get there :-P )

You did a great job with that car. Sorry if i slip off topic. Nothing like an old pontiac done right

[gator68428]

You did a great job with that car. Sorry if i slip off topic. Nothing like an old pontiac done right

Thanks!