Changing Gear Ratio On A T5

I kinda dislike the short first with 3.73s. I feel like when I come to a 4-way stop and it's my turn I need to rev it to redline fast and shift to 2nd you scoot out of the way. I just wish 1st was a tad bit more usable.

I do have 3.27s I could install
 
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My question would be why do you want to change the first gear ratio?
On a lower powered car (not saying yours is) the longer first gear robs the car of some fun.
I had a t5z and have a tko600, when the car had much lower hp, I didn't like either, so much so that before the terminator conversion I was going to goto 4.10's to compensate.

Adjusting the first gear ratio dramatically affects how much torque the transmission can handle.

To the OP, the main source for T5 upgrade internal parts is Astro Performance. Look at the packages they sell online. Some parts might seem superfluous, but they are in the package for a reason. Call them if you need to, they are very friendly people. The domestic performance manual transmission World is very small. While all these companies compete against each other, they all kind of work together. Trust me, AMP, Hanlon, Astro, Liberty, Southern Gear all know each other on a first name basis.

Kurt
 
So, what do y'all think. Let's say after building this supercoupe engine it has 425lb/ft of torque. Wouldn't that grenade my T5 no matter what I do to it.
 
A friend of mine has had the same t5 behind his 408 for years ( at least 8 ). He gets on it but I've never heard him speed shift. Its a 4 cylinder transmission. He's also about 70 so he knows the functional limits of things....that only comes with wisdom.

Guess I'll gain some wisdom after I blow mine up behind my engine combo.
 
A friend of mine has had the same t5 behind his 408 for years ( at least 8 ). He gets on it but I've never heard him speed shift. Its a 4 cylinder transmission. He's also about 70 so he knows the functional limits of things....that only comes with wisdom.

Guess I'll gain some wisdom after I blow mine up behind my engine combo.

It's funny how we still discuss this so much, but everyone really has different experiences with T5s. I grenaded one with stock power level that I literally only powershifted 3 times. My current setup has much more power and the trans is pushing 190k and this summer I beat the piss out of it. The most consistent advice with them is don't power shift and you'll be fine.
 
So, what do y'all think. Let's say after building this supercoupe engine it has 425lb/ft of torque. Wouldn't that grenade my T5 no matter what I do to it.
My 1959 Lincoln MEL 430 was rated 490 lbs-ft, we called it a "quarter-foot-ton". I ran a T-10 behind it in two different Falcons, first time a '64 I bought brand-new, second a '63 which had been a 6-banger.

Here's the '63:
img10910.jpg



The give-away is the fuel pump mounted atop the center of the timing chain cover, right behind the fan; all MEL engs. had it. Idea was, coolest place to prevent vapor lock. With stock C.I. Lincoln exhaust manifolds, this beast was something like 34" wide; move over 440 Chrysler!
img26210.jpg


img26310.jpg



Here's the same mill in the '64 Falcon. I bought it new almost a year before the Mustang was introduced, bought with 260 V-8, the 289 predecessor, and T-10 Warner 4-speed. That car did NOT come with a 9"; that I installed with the Lincoln. Had an 8.5" "baby 9" from factory. Peppy little car w/260, Chevy-eater with the 430. A nasty Mexican-National kid ran a 64 Chev. Bel-air "unbeatable" around our neck of the woods, I ran him from a 5mph "punch" out on County Line Road near Argonne National Laboratory, I think still McCook, Illinois, I looked over, he hunched like a maniac power shifting, I eased off each shift, every one just pulling ahead of his efforts with ease. I won TWO DOLLARS off those Mexicans! I figgered that T-10 just might bust.
car_pr12.jpg

Apologize for image "quality"; these pics were taken with a Polaroid "Swinger" camera, nearly 50 years ago.
 
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My points were only to address the feeling of the longer first gear, not the trans strength or the performance aspects.
While I don't know the mathematics offhand, going to the 2.95 first gear felt like removing the 3.73's and going back to like 3.08s, and imo, that ain't good...

I'm fine with it now, just remember my car makes a lot of power and torque down low.
When I had a combination of parts that made most of the power 4000+, the long first gear keep me out of the power band longer, which felt terrible at a stoplight.
 
I think there are two styles of roots blowers, both belt driven.
Ones like the old gmc style that stick through the hood and look all angry have a single rotor, the duel rotor like the blowzilla mega air mover and maybe the new one they put on the modular 5.0 I think is a duel rotor
Then there is a centrifugal (?) snail look'n thing that is also belt driven.
Am I close guys?
Can't hear ya, what? Oh crap, let me take this air hose outta my ear.
 
The old GMC 4-71, 6-71, 8-71 all have 2 rotors... They are just flat. Most of the newer style, (i've never seen the M90) have a twist and much closer tolerances between the rotors and case. Most rotors have a teflon strip to seal them to the case.

Am I mistaken about the supercharger, isn't it a twin screw (rotors)?

Yep. i was just googling it...I hope yours is a 94 or 95. The earlier blowers had plain aluminum rotors. 94 & 95 had epoxy coated rotors to reduce friction (heat)!!
 
The old GMC 4-71, 6-71, 8-71 all have 2 rotors... They are just flat. Most of the newer style, (i've never seen the M90) have a twist and much closer tolerances between the rotors and case. Most rotors have a teflon strip to seal them to the case.



Yep. i was just googling it...I hope yours is a 94 or 95. The earlier blowers had plain aluminum rotors. 94 & 95 had epoxy coated rotors to reduce friction (heat)!!
Nah, it's a '92 I believe. I'm going to send it off and have it rebuilt and ported. They will coat the rotors as well.

That's probably the first modification for the engine once I get it home.
 
Well, you PLAN on putting it in....but you have to PULL it out first!!! :bang:

If you were closer or I had an airplane...I would love to come help out! I shouldn't bust you too hard. I just need to solder about 150 wires together and my junk would run and I haven't managed to do that yet.
 
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I have no useful info to contribute about your transmission questions..
But.. If you can get Steve to show ya how to shoot flames out the tailpipes-the lower first gear will become a distant memory :D
 
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It's funny how we still discuss this so much, but everyone really has different experiences with T5s. I grenaded one with stock power level that I literally only powershifted 3 times. My current setup has much more power and the trans is pushing 190k and this summer I beat the piss out of it. The most consistent advice with them is don't power shift and you'll be fine.

TIRES! The transmission is the rope in a tug of war. You can run a T5 with as much engine as you want as long as it's on cheap street tires that spin easy. Everything starts breaking when you put slicks on the back.

Kurt
 
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As far as strength goes...the Z T5 is rated for 330 ft lbs. But that's computed to be a 100K mile trouble free life. So it you have 425 ft lbs and can live with a 25,000 mile life, there is hope! When my car was running I was putting 2000-3000 miles PER YEAR on it. So 12+ years would be ok by me! Plus a T5 weighs less than a 12 pack of beer. SO it's not too hard to swap!!

:cheers:
 
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When I finally get around to installing my TFS heads, I plan on leaving the stock 300 ft-lb rated T5 there and seeing how long it goes. I don't really rip around too much, but once in a while ill like to hit the 1-2 and 2-3 shift a bit. But I drive maybe 500 miles a year...it could last me a few years before something happens.

It blows up...I take it apart and fix it and stick it back in. These trans are very easy to fix, and parts aren't too bad.

I do have a spare parts t-5 I should build up so that I can swap it in if my original blows.
 
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