Changing Gear Ratio On A T5

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.

90sickfox said:

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.

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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.

Davedacarpainter said:

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.

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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:



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!





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.

Apologize for image "quality"; these pics were taken with a Polaroid "Swinger" camera, nearly 50 years ago.

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.