3.55 or 3.73

[dontlifttoshift]

3.70 is perfect with a T56. Make sure you get the 2.66 1st gear in the Magnum.

[CamaroAJ]

For sure the 3.70. I had 3.50 gears in my '67 with an LS/T56 and 6th gear at 70 mph lugged around 1500 rpm. You'll been much happier with 3.7x gears.

[DT69Cam]

370 or even 390 with a 6 speed.

[ADY]

Agreed, I had 3.73 with my t56 and rarely got it into 6th. Ended up going with 4.10, partly b/c going 25 mph in my hilly neighborhood left me right at a point where I was constantly shifting.

[califconstruct]

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4.11 on my T-56.. power band is perfect.

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[Ron Fox]

Should I go with a 5 speed instead?

[ADY]

The t56 gives you bragging rights, but unless you're putting down tons of power a 5 speed is perfectly fine for street driving and will save you from having to cut the trans tunnel in most cases.

[DT69Cam]

Originally Posted by Ron Fox

Should I go with a 5 speed instead?

I have a TKO 600. IMHO I would of never used the 6th gear. 5 speed and 373 gears with the .064 overdrive and your good to go.

[Ron Fox]

Originally Posted by califconstruct

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4.11 on my T-56.. power band is perfect.

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Any low lugging rpm's with the 4.11?

What do you think about aT56 with a 4.56 rear gear and a 2.96 tranny gear?

[Panteracer]

I have a tko 600 5 speed with 411's

gear ratios are 2.87 too low for me... 1.89 1.28 1.1 and .64
the .64 is too far away from the 1.1 4th gear to me
either 3 or 4th can't remember howl like crazy

I am going to change the rear gear to 3.73 but I think first
will still be useless and the gap from 4th to 5 still too much.. maybe the .83
would have been better but they said go .64

Wish I would have keep my old 4 speed as the ratios were perfect
except 1.1 was too low going down the freeway but everything
else was great for crossing, street driving, etc

Just my 2 cents

Bob Benson- Dreamin Ta's 70 firebird