what type of transmission?
 

I started a thread on the reliability of the cobras. During that thread alot of people replied and I thank you all. My next question would be for normal driving (distance not beyond 200 miles at a stretch) what would be the best type of transmission. I originally wanted to go with the four speed toploader wide ration. I'm running 390fe with a 331 posi rear. Any suggestions if this is the way to go. I wanted to keep it as original as possible. I know I can keep the original look with an over drive tranny. What is the best way to go?

Toploader with the 2.89 first gear--especially made for the lower rearend ratio cars. Available through David Kee.

Tremec T-600 roadracing gearset. 2.87 first, .82 fifth. Cruise RPM should be around 2300.

You can also order the Tremec 600 with a .64 fifth gear id you are interested

Why would you buy an orphan ratio, as the common wide ratio version is 2.78 first gear (close enough that you would not be able to tell a difference), and the 2nd and 3rd gears are the same anyways. I'd stick to the standard wide ratio toploader 2.78 first if you want a wide ratio 4 speed.

Anthony,

Are you suggesting to go with the toploader with the "normal" wide ratio? Are there any advantages to an over drive transmission verses a toploader for what I want to do with the car? To clearify, I don't want to constantly be shifting.

Picking a tranny is kind of like picking a wife. So many people have different tastes.

With the wide ratio toploader, you can run a 3.07 or 2.88 rear, and first gear is fine for take off, and I think 4th is fine for cruising. However, you give up a little wider spacing between gears, in my opinion not as good for medium or serious racing use.

All of the Tremec trannys are wide ratio 5 speeds, that is wide ratio 4 spd's with an overdrive. first gear in all of the tremecs is similar or deeper than 1st in the wr toploader, 4th is still 1:1, and 5th ( OD ) is either really high .65, or medium high 0.82.

I don't think you need 1st gear geared down deep, as the cobra is a light car, so you can get away with a 3.07/2.88 rear when using a 2.78 or deeper 1st gear.

I don't understand why David Kee came out with a new 1st gear ratio of 2.9, as the 2.78 is already in existence, and especially, that the new tranny also uses the same ratio's for 2nd and 3rd. 4th is always 1:1 . I just don't see the advantage.

Any of these trannys would be fine for a street machine. But from what I have read, it seems that many of the people serious about track use are using either the cr toplader or custom close ratio racing trannys ( Jerico , G-Force ). I figure, if you can pick your tranny in the beginning, you might as well pick a tranny that is geared optimally for what you want to use it. Probably the ultimate would be a custom racing close ratio 5 speed, as it would still retain the performance advantage, be durable, as well as give reasonable economy.

I think a good street 5 speed would be the richmond, get the 3.04 first instread of the 3.27, and go with a 2.88 rear. It's a true close ratio.

In my one car, I'm using a wr topl;oader and a 3.07 rear. It's fine for take off, and cruising is fine. Just when I was on the track, it seemed that ther gears were spaced a little too wide for my taste. It's a good combination, all gears are usable, but maybe just not optimal from the spacing standpoint.

The advantage of the TKO is the fifth gear for highway driving. If you are putting it in a more modern version replica, that would be your best choice.If you are getting a CSX or Kirkham you might want more authenticity,however more and more are putting TKO's in those as well. chuck

I just installed a T56 6 speed from a Viper. Seems to work well...

I've got a '99 Musty cobra with the original T-45 5-speeder. I WANT to, "upgrade" to a Tremec T-56 Viper six-speed. If anyone has had or heard ANY problems in doing this PLEASE lemme know I already put a, "mound" of dough in my baby and I want her running as smooth as she does with the T-45.

I can easily hit 150mph but than I am at redline. I THINK a Tremec will help me both in short end and high end speed. Am I right?

Thanks.

There has been some discussion on another thread regarding some problems with the T-56. You may want to search that thread to answer some of your questions.

Here's a new RPM calculator that might be of help regarding Tremec TKO 5 speeds

http://www.classicchevy5speed.com/RPM_calculator.swf

Scott