ajd3rd

I've searched the forums but still have some questions on a ZZ4 and Keisler 5 speed set up. I currrently have the body off and the frame totally disassembled on my 77 vette. I hoping those of you who have done this before can lend some insight:

1. The ZZ4 doesn't weigh as much as the stock motor. Do I need to change the front coil springs to have the car sit correctly?

2. I was thinking of purchasing the turnkey ZZ4. Will the serpentine belt setup work in a 77 Vette? Also will it clear the stock hood?

3. What gear ratio should I have in the differential to provide good off the line performance and good highway cruising.

Any other info would be greatly appreciated as well!

Andy

fauxrs

1. that shouldnt be necessary no.
2. Im unfamiliar with the serpentine on the turnkey zz4, if I had to guess I would say not, but that would be just a guess.
3. alot depends on which transmission - a tko500 with a .68 od or a tko600 with a .64 or .82od.


all things being equal a .64 od will allow you to run a lower rear gear (higher numerically) than for example the .82 would . but you also want to keep in mind the 1st gear of the tremec is low as well. For example I have a tko500 in my car with the original 3.70 rear gear. 1st gear is very very low, roughly the equivelant of running a 4.45 rear gear (if i kept the 4spd), based on my experience i would suggest a 3.55 as a better rear gear. YMMV

ZZ71S

I saw somewhere that the surp system something hits the Aarms I think it was the A/c comp.
I had a ZZ4 with a m 20 with a first gear of 2.52 and 355s and it pulled very strong.

Priya

The equivalent of a 4 speed with 4.45 rear gear would be ideal. I have a 4 speed with 3.70 and it bogs off the line in first, I have to rev the motor pretty high and ride the clutch to get a smooth start - very annoying. Keisler has an rpm calculator on its site. If I remember correctly a 5 speed with a .64 overdrive and 3.70 rear gears turns around 2000 rpm at 60 mph.

OzzyTom

The TKO-600 is probably stronger than you need with the ZZ4, but it allows you some flexibility if you up the power level later.

The TKO600 box also has better (closer) spaced ratios for a performance engine buildup.

1st gear at 2.87 with a 3.7 rear gear is a pretty good perfromance setup. 3.55 is also good, but 3.7 will get optimum rpm over the quarter mile in 4th with typical diameter tyres. Better gearing advantage for overall better performance.

Get the box with the 0.68 OD ratio, and you have an ideal cruiser for the highway also.

Brandywine

I have a ZZ4 with a serpentine setup from March (includes A/C) and a Keisler TKO 500 5 speed. I have a 1980... not to different from a 77.

1. No.
2. Yes
3. I kept the stock 3.08 rear and the Keisler TKO 500 gearing in 1st make it something like a 4.10 rear. Great off the line and... low RPM's in 5th. Makes for great highway cruising.

Binnie77

You might want to check out these:

TKO Install in a '77

ZZ4 Install in a '77

PHPD7102

Great info here, thanks guys.

FKING1

Have a ZZ4 with Keisler TK600, .64 5th with a 3.70 rear.
Autocross and is a perfect setup. 1st will burn rubber at will. Highway cruising in 5th is great.