.82 or .64 TKO?

[Flash68]

Originally Posted by Josh69

Have you driven it yet as is to see what it behaves like in OD?

I have the TKO600 with the .64 and a 3.73 in a Moser 12 bolt with 25.5" tires. I would have gone with either the .82 or a 3.90/4.11 if I had it to do over. I'm around 1900rpms, and it wants to load up. I'm running a single plane and a quick fuel 750 race carb built for E85. I'm looking to supercharge mine as well, and have some of the same concerns. I imagine it'd be worse with the blower drag on it in my situation. I'm heading to the dyno room to try to sort it out. If not, I'll be dropping in some 4:11's.

My cam is a hydraulic flat tappet 236/242 @ .050, 108cl, .516/523 lift. I guess it really comes down to how your motor wants to run under load at 2K rpm's or less. Right now you'll be in the 1800-2000 range at 55-60. Fourth gear can be pretty annoying with a 3:70 at 60mph if you can't hit 5th. I drive 30 miles each way to my office on a 2 lane where it's hard to get past 60mph.....it sucks not using the OD in those situations.

Car is not done so no I have not driven it yet. I shouldn't have loading up problems at low rpms since I have EFI. I failed to mention that I guess.

[Blown353]

Originally Posted by Flash68

I shouldn't have loading up problems at low rpms since I have EFI. I failed to mention that I guess.

Depends on the cam-- regardless of induction some cams just aren't happy being loaded under a certain RPM and the engine will surge and buck no matter what combination of timing and AFR you give it.

With 3.70 gears and that tire diameter, my preference to make it a freeway-friendly car would be the .64 gears unless the cam is really big. But knowing you have Don's old motor the .64 OD should be just fine, I seem to remember that cam "cleaning up" around 1600-1700 rpm from the few times I was in the car, so you should be able to shift into 5th around 50-55 mph and it will be happy.

Why are you having to send the TKO back to move the shifter? You can easily switch the shifter location yourself between the 16.25 and 19" location; you just unbolt it and rotate it 180. The only more complex shifter relocations are if you have the shifter located really forward under one of the midlength covers instead of on the tailhousing, that gets more involved and needs extra parts.

[Flash68]

Originally Posted by Blown353

Depends on the cam-- regardless of induction some cams just aren't happy being loaded under a certain RPM and the engine will surge and buck no matter what combination of timing and AFR you give it.

Makes sense. I don't think is cam is really huge based on what I know.

Originally Posted by Blown353

With 3.70 gears and that tire diameter, my preference to make it a freeway-friendly car would be the .64 gears unless the cam is really big. But knowing you have Don's old motor the .64 OD should be just fine, I seem to remember that cam "cleaning up" around 1600-1700 rpm from the few times I was in the car, so you should be able to shift into 5th around 50-55 mph and it will be happy.

That's a pretty low rpm so yeah that should be okay.

Originally Posted by Blown353

Why are you having to send the TKO back to move the shifter? You can easily switch the shifter location yourself between the 16.25 and 19" location; you just unbolt it and rotate it 180. The only more complex shifter relocations are if you have the shifter located really forward under one of the midlength covers instead of on the tailhousing, that gets more involved and needs extra parts.

I am sending it back to Keisler cuz they have to modify the tailshaft or some part that apparently only they should do. I asked them it is more work than just switching that plate around. This will also allow me to run the Pro 5.0 shifter base that I want to run now, which I cannot in the tranny's current form. It's pretty cheap actually and they are just gonna switch this tranny out for a new unmodified one from Tremec where they have not messed with it yet except for the 19.25" shifter location (currently it is 16" - so, a 3.25" difference).