Is it me or alot of people over looking something that would give you a lot more power to the wheels with out having to do one thing to the engine... Droping your car off at a good tranny shop and letting them rebuild you transmission so you could have 95% of the engines power to the ground....has anyone tired this yet? or is going to try this? i know you guys doing swaps and turbos might really want to look into this.... cause whats the point of having all that power if your losing 30% in side the tranny....


let me know why you guys think?

-macavely+Oct 23, 2003 - 6:25 AM

the problem is that all those modifications are $$$$

for i think $4k i could get a tranny from level10. it will come with a shift kit, performance TC, fully rebuilt with better parts, and the tap shift thing to control it if you want. after all that my ET might have 1/2 a second to 1 second shaved off(depending on the trannies condition before the rebuild/replacement)

that would make for some great gains in efficiency, but i think that the way some people see it is that they pay all that money to not technically gain any HP.

with 5spds, it is worth it to get a better clutch, but autos can have a lot more done to themfor a lot more $

if i had to spend another $4k on my car, i would put it into internals for the engine make more power that way.

personally, after i get a fmic and fuel pump, i will be done with my car performance wise. after that im gonna save up for another car.

Then only thing you can really do is make things lighter. Drive axels and flywheels can be bought lightened, but gears themselves i havent heard of. And increasing or decreasing the gear ratios will only affect top speed and acceleration.

just remember that the 5sfe is only 135hp at the crank. so, even if you worked some crazy tranny magic the the most you could ever get out of the car would be less then 135hp at the wheels.

ok i have a question for ya'll have any of you ever rebulit a tranny... and if so did it really take you 4k to do it?

-macavely+Oct 23, 2003 - 4:49 PM

the efficiency of the trans is not likely to increase by a lot. It would increase somewhat. The most effecient gear sets are planetary (auto trans) running around 98.5% on average. But for ever set you go through you have to multiply (98.5 x 98.5). Once the torque converter locks up in an auto tranny, your efficiency is ussually as good or better than a manual.

Gears in a standard transmission are less efficient than planets, but there is ussually only one set of gears that power is being transmitted through. In order to improve the effeciency all of the gears would have to be replaced and it would not be a large gain. a good exhaust would probably give you more gains.

Just does not seem like an economical source of power, that being said, synthetic trans fluid would be a good cheap improvement.

17-20% total drivetrain loss is pretty typical for a street car. It is possible to improve that number by a few percent by having REM treatment done on all the gears and the splines on the input shaft. We do this on a number of our race cars and its a worthwhile improvement but its expensive.

Definitely use a good synthetic lube, 5spd or Auto, probably the best gain for your tranny dollars. I recommend Amsoil as they are the oldest and largest maker of synthetic lubes.
Look up your local Amsoil dealer in the yellow pages under "oil" or order online thru my site:
http://www.lubedealer.com/cthompson/

(the preferred customer plan online is the most cost effective way to buy if you get together with someone else and order enough for a couple of cars, maybe throw in one of their foam air filters for your stock airbox?)

(Or become a dealer and make a little extra cash on the side supplying friends and neighbors? )

(Sorry guys, couldnt resist making a sales pitch, but it is a great product and I get to deduct a lot of mileage and expenses)

Amsoil is a great product. I also highly recommend BG Synthetics (available only through your local distributor www.bgprod.com) and Mobil 1.

I use Mobil 1