Hello everyone!
I am converting a 1975 automatic transmission to a manual, and I was wondering what transmission you all would reccommend. Any other tips from anyone who has done so, would be quite welcome.

As far as money is concerned, its more a matter of figuring how long I will need to save up for it. I'd prefer something midrange though.

 

Richmond 5pd overdrive or TKO500. PM Sent

 

keisler.com will sell you an entire conversion kit.

http://forums.corvetteforum.com/c3-t...-how-hard.html

 

Converting to manual was one of the best mods I ever made to my '78, but you didn't mention anything about your power and its range, your diff gearing, or your primary usage. Nailing that down would sure help reduce the guesswork...


TSW

 

Thanks for the quick response.
I think I will hold off on this conversion for awhile, while I deal with other more serious issues, such as the interior and exterior.

 

Hope I didn't scare you away by the cost, you could always find the parts yourself and get a 4 speed and have it be much cheaper

 

I got this car quite recently, and I believe that it is pretty much stock, except that it has performer intakes, a 600 cfm edelbrock carb, and dual exhausts. I have no idea on the power rating, but my guess is somewhere between 200-250hp.

I use this car primarily as a daily driver, but I also take it out in the country and go fast.
So i'm really not looking for anything too crazy right now.

 

I am planning on eventually doing a complete overhaul and turning it into a performance vehicle when I have a little more disposable income though, and when I have another car for driving on a daily basis.

 

Cheapest route for the current power level would probably be the T5, but if you plan on upgrading to 450-500 hp a Tremec or Richmond 5 spd. If you only plan on a mild 400hp or less build and not launching the car with slicks the T5 can be made to handle that kind of power. G-Force and Astro have parts to beef up the T5 that separately do not cost a ton of money and if you are good with tools are easy to install. You only need a few tolls to work on the T5, and they only weigh 75lbs.

 

If i'm not wrong, this is the transmission out of an S10, right?
Noob question, but is there a difference between different T5s from different vehicles? Because on their site, they have like 30 different models.

 

I installed a Keisler 5sd complete kit and could not be happier

 

My other qualm about a conversion kit, is that I'm afraid i'd burn through the transmission in no time.
The only manuals I've driven have been farm equipment- not the same ball park. So I definitely want to get a used one first to play around with until im comfortable enough to use a good one.

 

A quality, HD transmission will take considerable abuse, so I'd suggest basing any transmission decision on where you plan on eventually taking the entire project to avoid spending twice down the road. And, since performance is your ultimate goal, optimizing your gearing will be more critical than for mere cruising. For the sake of discussion, I'm assuming you'll end up with an OD transmission.

Of the manuals out there, you've probably already found that you do have some gear ratio choices, and IMCO how deep you want/need 1st and how much OD in top gear are the most important such considerations. In most cases, the steps between 1st and top gear will have been thought out by the manufacturer appropriately.

The deeper (larger number) your current diff ring & pinion ratio, the taller (smaller number) 1st gear you can go with. A good rule of thumb for total gear multiplication in 1st is ~10:1, but you can get away with a little less if you have ample bottom end torque, or if off-the-line performance is of little importance. Much more than 10:1 and you'll waste more time shifting than making progress down the road. Exception: really tall tires.

As for top end, having the tallest (again, lower number) total gear multiplication in top gear isn't necessarily the formula for achieving the highest terminal velocity, so bear in mind that along with several other variables the power curve of the prospective engine has much to do with determining the better top gear ratio.

The wider is your engine's power band, the fewer gear steps are necessary. For my particular application/purposes, the Richmond Super Street 5-speed OD with 2.89 1st and .077 5th currently looks like the best selection available, and IMCO I cannot justify carrying around a 6th gear, but then you shouldn't necessarily base your decision on what I'm doing. Hope that helps your thought process...

 

No, you would use a world class from certain year mustangs. Or you could buy a new one for about $1200 from a vendor. The other good thing is they are plentiful used. Thats what the swap plate uses is the mustang bolt pattern. You should search that on here many have done it and done some nice write ups on this conversion.

 

So would this transmission work then?:
http://portland.craigslist.org/wsc/pts/1599227459.html

 

If its from a mustang , yes, but you want to make sure the numbers indicate world class.http://www.5speeds.com/t5/
This website can help decipher by the tag numbers on the trans. Though if you are going to rebuild, I believe it makes no difference, because all the weak parts are swapped out for the upgrades. You may want to clarify that with one of the trans shops.

 

Thanks. I will let you all know how it turns out!
Thanks for all your input.