Tremec transmissions
 

Here is everything you ever wanted to know about Tremecs.


http://www.ttcautomotive.com/English...cts/tremec.asp

Tremec TKO
 

Good call,

Very interesting site. If/When I build my cobra I'll be using a 5-speed and probably a TKO. I'm assuming it will withstand the torque in a lighter car but was curious about this approach.

Do you use a tremec? If so, how much HP/TQ are you producing?

If I were to use the engine from my race car then It will be producing a little over 600hp but I'm not sure about torque, probably in the 500 to 550 range.

Thanks for the info, I added it to my favorites list in the automotive folder.

Damon,
I am currently building a Dart sb for track use only. I will be reinstalling my 3550 Tremec and I can tell you I will have my fingers crossed the first few times out. I will not be doing any Drag race starts and I am a pretty smooth shifter so perhaps this trans will live long enough for me to save for a Jerico rr trans.
HP??? Who knows? more than 100 less than a 1000. Same with torque.
Cranky:3DSMILE:

Racer x, I had the tko apart several times to replace syncro's and sliders as it was not shifting well or not at all. Then it flew apart, broken third gear at willow springs a year ago. I now have the tko2 with the hardend cluster and hardend third. I have had good luck so far. Scott

The T-56 looks like the only one that will handle the TQ in the 475-500 range. But guys have stated that the 3550 is enough for a street driver with little racing...

GS

I have put 3550's and TKO's behind motors that made over 500 ft/lbs without the expected failure rate one might expect if they read the torque rating in the manual. The biggest problem the tremecs have is when guys shove them into gear while trying to speed shift, that uses up the synchros. At their low cost, you could replace it (whole tranny) twice for the cost of buying a beefier tranny. They are perfectly fine for spirited street driving and the occasional track day, not good enough for real racing.

In the Cobra, you can get by with more hp and torque compared to the tanny rating due to the inability of the Cobra to take full advantage of all the hp and rorque available. Try and do it in the lower gears and you just spin your wheels. Unless you abuse and pop the clutch, you will virtually not be able to convert full your engine torque to the clutch. Once you are rolling, the peak load is not as critical.

I plan, however, to install a TKO II to insure with its additonal capacity acting as a measure of reserve as insurance to avoid problems. I also like the less tall step from 4th to 5th gear. For street purposes, you can go to 5th gear at a lower mph at a street drivable speed instead of a freeway speed. If you want to race, it is bettter for road racing. You limit your top speed but you are able to use 5th gear more. You have an advantage on curvey courses.

Tremec TKO :(
 

Tell ya what. I have a TKO in a FE Cobra thats 3 years old with only 5000 miles. This car has seen little if any track time, and never had slicks. The TKO lasted right at 5000 miles. Now third gear is rattleing bad and so are the other gears. Wrote a nice letter to the National Sales Manager for tremec. No responce! Boy thats the customer service I dream of. I have had sports cars all my life, ran most pretty hard, never had a transmission only last five thousand miles. Others were daily drivers as well. This car just goes to car shows and the grocery store. Thank god its not a daily driver. That would mean about 8 tremec TKO's a year.

ZZZZZZZZ-
How many 11 second passes on street tires do you have on that that TKO?? Maybe that has something to do with the reduced service life of your trans???

Chaplin,
Only 11 sec. from car show to grocery store. I'll bet he never slamed third gear real hard.:rolleyes:

Car show to Grocery store
 

Now i did say the car did see little track time. Give you an idea how much time on the track. It has been to the dragstrip 2 times in 3 years. Thats including one run and gun. Maybe 15 times down the quarter mile total in the life of the car.. Obviosly, this is not counting what happens on the way to the grocery store. But still, 5000 miles out of a transmision. They can do better than that. Heck, I would have at least been happy with a reply from Tremec on this issue. O, I dont really have a problem hitting 3rd gear. My problem is once i am in it. Feels like the trany going to fall right out.

$0.02.

Installed new, blueprinted (Liberty Transmissions), T5Z behind tweaked (hydraulic roller, TFS heads, usual stuff) 351W. Car is daily driver, cruiser, road trips, and some highway horseplay. 12,000 miles on car now and no problems with trans. Shifts like a Honda, and seems like it will last as long as the car does.

For track use, why use an OD trans? Would a 4 spd toploader not give acceptable service? For BB street use, a Richmond 5 spd would seem to offer strength and better gear ratios than Tremec.

ZZZZ;
Most people are having real good luck and abusing the heck out of them with no problems. What lub you using?

gn

Not to beat a dead horse to death but you can get, in some instances, the Toploader in varying ratios, over and above the traditional close and wide.

Just recently, I purchased from David Kee the gearing for a Road Race Toploader known as a white stripe, "Sebring Box" that has a 2.13 first. These were used for racing applications and were very rare. He is manufacturing this particular gearing for said application. You might want to look at his site www.4speedtoploaders.com and look under the heading "white stripe" transmissions and the available gearing that was once available. Some of the ratios are peculiar, but the favored box is the 2.13 Sebring.

power to weight ratio
 

I haven't heard anybody mention anything about the weight of the cobra as a factor. If you consider that the earlier mustang cobra Rs used the 3550s and I don't think they make any modifications to it, and the cobra R has a curb weight of 3590lbs suggests that the rear tires, driven by a 385hp 330 cid motor would grip the pavement with less spin than a 2485 lb cobra. You can probably factor in the shorter drive shaft as well (+/-). But the 3550 should be able to handle the high output stroked windsors. When you deal with the big block HO motors, the torque curve will do more damage from the standing start. The big spline top loader can take a huge pounding from the big block, but the tremec seems to be a pretty good bargain. My SPF was purchased from the Olthoffs and they have said the only difference between the 3550 and TKO was the number of splines, but it's essentially the same transmission. But rather than debate the differences here between the TKO and 3550, if the Olthoffs are willing to put the 475+hp windsor together with a 3550, then that's fine with me. If you go to Jegs.com, they list the 3550 as follows:

Straight out of the Cobra ''R'', this is the heavy-duty transmission youv'e been asking for! It features improved synchronizers and 350 ft/lbs torque capacity. Gear ratios are 3.27, 1.98, 1.34, 1.00 and .68. Requires bellhousing #397-M6392-R58. Will fit 1979-93 with #397-M5059-A crossmember. 1994-95 requires driveshaft and crossmember modifications and a new clutch fork.

$1,424.99

But I do think that the point somebody here made earlier about spending all your cobra's toque spinning is sort of a built in damage control feature. The way I look at it is that if you put 1000 pounds in the trunk of your SPF or ERA putting out 500hp, you'd stress the hell out of the tranny, but when it's light as a feather, the 350lb torque limit suggested by jegs should be reassessed.

Any thoughts??

For racing applications, I have no idea why one would use a 3.27 or a .68 ratio. Unless you are operating a tree service where stump pulling is required, the 3.27 first would seem useless. The middle three gears make sense, as they are right in line with a Toploader Wide Ratio.

Cal, The reason for the very low gear Tremec in the Cobra R is because the cam does not come on until 4000rpm. The low gear gets you there very quick. A BB or a sb with a low rpm torque starting point will not need that low first gear. As far as the OD, way to tall.
My .02

Cranky:3DSMILE:

Torque is torque no matter how light the car is. I remember someone bringing me a small spline toploader out of an ERA with a stock medium riser 427 with the input shaft twisted like a barber's pole. The car had BFG street tires on it and was a street car with no trips to the drag strip.
One thing to remember about using an overdrive transmission is the engines being used in most Cobras are not made to run ultra low rpm's on the highway. You could be doing more damage than good by trying to have the best of both worlds. The cars the overdrives were made for have computers and fuel injection to keep everything in check at low rpm cruising.

Hey ZZZZZZ
 

I too am building a Midstates with 428 PI and TKO.

Did you have the bellhousing and adapter aligned with the crankshaft center line????

How long ago did you buy your transmission ???

Where are you located in MO ???

Thanks,
Bill Cook


:D

Wicked,

I did have the bellhousing and adapter aligned with the crankshaft center line. The problem is in the transmission, not the installation. Also, been running all the recommended fluids. I Live in Chesterfield, its about 20 min West of downtown St. Louis.