Racing Transmissions?

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sicbeing

sicbeing

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I am trying to further gather information about racing modifications and came to the conclusion that I don't know where you can ask people about transmissions if you plan to race your car. I'm not sure what makes one transmission better than another, or what makes one more efficient to use with lots of power over another transmission. I also can't seem to find where to even buy something like a powerful transmission, or even how pricey one can be (I'm guessing 1-3 Grand).

If any of you can help me out with some info, I'd greatly appreciate it. This is one of the many times google has failed me when searching for car mods. Believe it or not it comes up with a bunch of needforspeed/SRS video game crap and ads on ebay for vehicles.
 
Well auto trannies are normally used for drag racing only. Here the standard for drag-touring cars is a beefed up AODE (Ford) or 4L80E (Chevy), or just any stock automatic with higher line pressure and a high-stall converter. These are normally good for 600-800 hp.

In terms of manual trannies, with a good clutch most will hold quite a bit of power. Commonly used in RWD V8 applications in the T56, which is good for about 1500 hp. There are also straight-cut Hewland trannies, which require double clutching and are rather difficult to drive but very strong.

If you are just interested in firming up your stock Eclipse manual tranny, look into firm (poly) bushings for the shifter cables and prehaps a stiffer tranny/motor mount. Most vaugeness is caused by either freeplay in the shifter mechanism, or the motor/tranny moving relative to the shifter and changing the location of the shift detents.


EDIT: This is none of my buisness, but for your car I would look into a good set of tires first. Then firm up the suspension. The worry about the tranny/motor.
 
I plan on at least keeping aside some money for the transmission. I was told by a few people to get tires first and i think it makes sense to make your car handle better first, then work on everything else. I wanted to work on the suspension and trans and then the tires.

Most the stuff you said before your edit is almost like jibberish to me, but I appreciate it non-the-less cuz it gives me some sort of clue.
 
I think the stock transmission should be fine for racing.

The only people I've heard of messing with transmissions are drag racers, and then people trading up for newer transmissions from the manufacturer... like Civic guys buying transmissions off of japanese Civic SiRs or MR2 guys buing transmissions from newer Corolla GT-Ss with six speeds and an LSD.
 
Basically, for your Eclipse no internal transmission work is needed to hold the power that even a heavily modified stock engine can put out. Most manual trannies are really very well built. If you want firmer, more accurate shifts, look into a polyurethane motor/tranny mount kit and also improved shifter cables. Maybe you might want a grippier clutch, but you can always do that when/if you burn the first one up. And you can always change the tranny fluid, it is an easy backyard job.

EDIT: :D, restmah beat me to the puch
 
What car are we talking about??? Some people mentioned an Eclipse, but what year/model??? The only Eclipse models that have any trans problems are the AWD models. And even then, its mostly the transfer case, not the actual trans, that needs work. But, also, thats only when power gets to a pretty high level. When the power gets up into the 350hp range, you can run into problems with shift forks and synchros breaking. But again, thats not real common in mild tuned cars.

My trans and transfer case were rebuilt by Shep Racing, and have been bullet-proof ever since. Again, I don't know what model Eclipse you are talking about. But, if its a 1G or 2G, you can send it to them. They know their stuff. It was under $1000 for the total rebuild, but I believe you can buy a new built trans from them for about $2000. Hope that helps. Let me know what model we're talking about, and we can go from there.

Hilg
 
Who told you Hewlands need double clutching? Especially since Hewland isn't a tranny manufacturer. Hewland does transaxles for mid-engine layouts LIKE THE MOSLER MT900.

Straight cut gears don't require double clutching. I know. I have them in my MGB. What they do need - if you don't have some seriously well built synchros and if you want to shift fast - is rev matching: keeping the engine speed level between gear changes while still being easy on the clutch.

The most common racing gearbox in RWD applications is the Jerico. Jericos are 4speeds most commonly found in stock cars, off road trucks, late models, drag cars, and tube frame/semi-tube frame road racing cars. One of the greatest assets of the Jerico is its abilty to be upshifted clutchlessly thanks to its unique "slider & tooth" gearset. Plus you really, REALLY cannot break a Jerico.

Seriously. Jericos make Muncie M22 Rockcrushers look fragile.
 
Its a 'dog' box that has no synchro and might require you to 'double clutch' - our Cortina has one (a Jack Knight) but with racing usage the change is fine because you are always in the right rev range for changing gear, down changes are where you have problems with baulking - a bit of heal-and-toe helps. Not many road cars really require double clutching these days, its something that died in the 50's.

I wouldn't bother saving for a 'racing' trannie for your Eclipse - if you break the one you've got, which is unlikely, you can just buy another referbished one. If your car's going to spend more time on the road than on the track you'll be much better off with the standard box.
 

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