So is there anything else after doing the TC and rear gearing that can help get the power to the ground more efficiently over stock? (other than replacing or rebuilding the transmission)

 

Haha yeah you guys have seriously impressed me with your knowledge. I've always been a manual tranny guy so I dont know much about these automatics.

 

The gearing has nothing to do with getting the power to the ground better. All gearing does is change the torque curve at which the peak power occurs at. That's all. You get no increase in Dyno performance by getting gears, just a faster peaking tq curve is all.

If your really concerned with power and have mechanical abilities, go manual Trans. You'll pick up minimum 10-12% power increase to the ground over an auto made by Chrysler.
Otherwise, a new TQ'verter, better cooler and synthetic fluid will help.

 

Wikipedia has a great explaination of torque converters. More or less what everyone has said is right, but this has some more interesting bits.

It's easier to see how a 4,000 RPM stall converter with a 3.5 : 1 stall ratio would be very desirable on the strip, and very annoying, hot and inefficient on the street.

http://en.wikipedia.org/wiki/Torque_converter

Pretty neat machines. We've come a long way since the 2 speed non-lockup Powerglides of the 50's. I'll take my manual though

Also, everyone should read up on HP and torque...engines do not make horsepower. Engines "make" torque. They apply torque to a load. In fact, without a load, engines don't make much torque (or "horsepower") at all. Once you measure that torque, by loading the engine down, and multiply it by the rate the engine is rotating, you've created an artificial unit called horsepower. Very useful, but also a great way to confuse people. A "faster peaking torque curve" is an example...you could have 9:1 gears or 0.9:1 gears, the torque curve had better look the same every time, or else the engine has changed.

It's fun to think about and learn once you understand...HP isn't everything. Why would you rather have a 290 HP Cummins in a 10 wheel dump truck versus a 390 HP Hemi?

Anyway I digress. Manuals rule

 

he can make more WHP by going to a smaller, lighter TC...not as much as a manual, but better than the stock TC.

also, i thought that its been shown that changing your gearing does change your whp...we had some guys on my mustang site who went to bigger gears, and i thought that they actually made less on the dyno...

 

I understand that the rear gearing does nothing to creat power, like you said dog it just affects the tq curve no power gains, however, by adjusting them I have improved how that existing power is being used at the wheels. Point being since I installed the 4.56's, my acceleration has been much quicker, I get harder launches, and better times over the 3.92's that were in there stock.

The torque converter also should not add any power, instead (if I understand this correctly, if not please correct me) it will remove or free up some of the parasitic loss through the drivetrain which essentially improves how the existing power the engine is producing is getting to the wheels.

So with all that being said, with the new tq converter improving how the power gets to the wheels and the gears improving how that power is being used at the wheels, is there anything else that can be done or should be done in order to help the system even further (besides switching to a new transmission, converting to a manual transmission or rebuilding the current transmission)?

 

No change in power. if there is a change it's because the dyno was not set-up to run in a 1:1 ratio for the pull run. We did a 4th gear 1:1ratio pull and compared it to a 2nd gear pull with the dyno set at 1:1 and there was a power loss. Then we ran it in 2nd with the dyno set accordingly and it gave near identical readings.

Maybe if you were to get into something like a 5:88 ratio i could see loosing a few rwhp because of so much gear contact but I doubt it could be anything that's even worth arguing about.


Truckin, your understanding of it is correctl!

Replacing the TQ'verter is like installing an E-fan as far as HP is concerned.

 

ill try to look for the thread..the guy went from something like 3.31s to 4.56s and the dyno showed a drop, IIRC...but there was a constant dispute about the results...then again, it seems that no matter what the reason may be, dyno results are always disputed...

 

Cool. Thanks man. That was easy.

 

So is that about all I can do to the drivetrain to remove some of the parasitic loss or is there anything else besides the TC that can further reduce it?