the reason an automatic trany is slower that a manual?

[bnpimpn]

haha, i realise that you cant make power from a trany....i actually meant what specific parts he recomends to transfer the power most effectively and reliably.... and what sort of shops will actually ship parts into Canada. im sick right now so i think one thing and do another...

 

[StyleElements]

it's not weight, its not shift speed, and no not drive train loss

sure about that? it has nothing to do with 35% drivetrain loss?

 

[definitiveno]

sure about that? it has nothing to do with 35% drivetrain loss?

is that a factual number, better yet are drive train losses in either model (auto or manny) measured accuratly in percantages? No.

 

[98TalonTSi]

I've never heard of an actual %, just numbers thrown around....
I guess the only way to get a true rough idea, and even then it's tough, but is to have two identical dsms (if that's possible) and have then dynoed.....
Does it really matter that much why we are a little slower? It's about finding the right setup...

 

[StyleElements]

is that a factual number, better yet are drive train losses in either model (auto or manny) measured accuratly in percantages? No.

Yes.










[/thread]

 

[definitiveno]

Yes.










[/thread]

I must respectfully disagree.

 

[StyleElements]

I must respectfully disagree.

Your respectful disagreement is respected

 

[transdude]

Anyway, we ship to Canada all the time

-John

 

[remmargorp]

nothing in the tranny will increase power.

it will shorten shifts, and prevent clutch slipping.

The transmission does not add horsepower or torque to the flywheel.... but it has the ability to raise power to the wheels. Which is still increasing power, not every car can produce 200hp at the flywheel and 200 at the wheels... better drive-train parts will help increase power to the wheels (transmissions are part of that equation)

I know this is a different world when I talk about the following cars... we had an 89 camaro with the base 305 and the 700r4 transmission (completely stock)... we swapped out the 700r4 with a 5-speed, ran slightly better times, but not a whole lot, installed just a shift kit on the 700r4, swapped it back in, ran better times then the manual. So in that sense, a simple modification on that particular transmission increased it's performance over that of the manual. Just an example of how not all automatic's are worse then manuals and/or the other way around

 

[Car Cannibal]

The stock converter has a k factor of 1:47 and Precision's Dragon is 2:55.
Most modded DSM's can produce 400lbs of torque, stock converter puts about 588lbs through the trans where the Precision will put out 1020.
Which one would you rather have?

Automatics generally eat 5% more drivetrain loss than manuals and then add on the stock converter is heavier than the aftermarket billet cover, small circumference ones.

Install a high stall, high k factor torque converter and the automatics out run the manuals.

 

[bnpimpn]

The stock converter has a k factor of 1:47 and Precision's Dragon is 2:55.
QUOTE]

is that torque converter available for 95 talons? What are my options when it comes to brands of torque converters/shift kits. What sites...any links? I've already seen IPT's web site, any others?

 

[91Bomb]

I think the gearing has the most to do with it.

It's a 4-spd vs a 5-spd with different final drives. If the gearing and final drive were identical the 1/4 mi times and speed would be MUCH closer.

Take a car like the current G35 sedan -- The 1/4 mi times and speeds are very close betwem the a/t and m/t's. They're both 5-speeds and judging by the 1/4 mile #'s they are no doubt using the same gear ratios and final drives.

The slghtly slower a/t model could easiy be accounted for by 1) the a/t adds extra weight to the car 2) the shifts on a G35 sedan aren't as crisp as they would be on a performance car like the C6 a/t or even our dsm a/t's. 3) There usually is a 5HP loss in the driveline of an a/t.

If you look back at some of the muscle cars fromm the 60's you would see that in some cases the a/t models were as fast or faster in the 1/4 mi as the m/t's. Of course the bigger and torque(ier) V8's helped even the field between a/t and m/t.

If our a/t DSM's used a 5-spd with the same gearing and final drive #'s as the m/t's they would be much more competitive. I sometimes lose sleep at night wondering what a 5-spd Dsm a/t would've been like. (the WRX also ues a 4-spd auto, WHY?)

 

[Geezus_Aach]

...
Take a car like the current G35 sedan -- The 1/4 mi times and speeds are very close betwem the a/t and m/t's. They're both 5-speeds and judging by the 1/4 mile #'s they are no doubt using the same gear ratios and final drives....

G35 sedan or coupe has a 6-speed m/t ...5-speed a/t

 

[slovins]

IMO automatic transmissions are slower for a few reasons:
1) They are heavier than a manual transmission
2) The time it takes for an automatic to react
3) Autos shift when they want, they don't completely rev out the gears
4) The gear ratio, which is what I am not sure on , but I believe probably plays a role.

 

[91Bomb]

G35 sedan or coupe has a 6-speed m/t ...5-speed a/t

Bad example on my part. How about the '04 models?
I'll have to try and find some 1/4 mi #'s for cars that are using the same number of gears and using the same gear ratios and final drives in their a/t and m/t versions. This would be a good way to make a comparison.

BTW, the EPA fuel mileage rating for a 1g turbo a/t is 19/23 vs 20/27 for a 2g turbo a/t. This leads me to beleive that the gearing in the 2g's are different than the 1g's and not as good for racing. And the EPA also has the '95 model rated at 23/27 vs 20/27 for the '96-99 yrs. Are these numbers an indication that the gearing was different or is this an EPA thing?

 

[definitiveno]

Bad example on my part. How about the '04 models?
I'll have to try and find some 1/4 mi #'s for cars that are using the same number of gears and using the same gear ratios and final drives in their a/t and m/t versions. This would be a good way to make a comparison.

BTW, the EPA fuel mileage rating for a 1g turbo a/t is 19/23 vs 20/27 for a 2g turbo a/t. This leads me to beleive that the gearing in the 2g's are different than the 1g's and not as good for racing. And the EPA also has the '95 model rated at 23/27 vs 20/27 for the '96-99 yrs. Are these numbers an indication that the gearing was different or is this an EPA thing?

the 2g has a lock up torque converter wich aids in better milage on highway