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Discussion Starter #1
Well I built that motor last year that ya'll helped me with and now I need to finalize the drive train, but I don’t know how much horsepower and torque I am playing with.

69 351w bored .30 with hype pistons flat top
Comp cams extreme energy 262
Weiand stealth dual plane topped with a 650-speed demon
Afr 185’s with 1.6 roller rockers and hardened push rods
Arp everywhere

I would like to swap out my C4 with a T5 and keep the original 8” with an upgrade to 3.55 or 3.80 gears. The other option would be to go with a tko500 or 600 with a 9”. I will not be racing with slicks, just fun driving. The later option costs a lot more as you all know and might call for tunnel adjustments for fitment.

I have never driven anything like this except for my friends 96 cobra 5-speed and that was fun, a lot of fun and that’s what this build is aimed at. The research I have done has shown that my system looks to be on the fence, from a horsepower-torque perspective. Darkhorse said keep it light and it will hold while modern suggested going up to the bigger set-up.
Does anyone have this type of set-up or have any idea of the horsepower/torque I might be making (my original goal was an engine-combo that was making more than 300 hp but very streetable)? And which set-up might fit the bill?
 

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8" rear should be fine, a friend of mine has one in a 39 chevy with a stroked big block and he beat on it for three years before the 8" finally let go. Just make sure you have the heavy T5 trans, I think the trans would be the weak link in this setup.
 

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I'm sure you've got more than 300 HP at the flywheel, and already have a strong running, very streetable engine, so you've probably already met that goal.

You'll probably be fine with the 8" for a long time, and either the 3.55's or 3.80's would really wake the car up, so the question really comes down to the tranny.

If the car will never see track time, you'll probably have a nice friendly relationship with a T-5. If you decide to put slicks on it, though, and :track: (sorry, first time I've ever used that emoticon *LOL*), then your relationship with the T-5 could be shortened.

One of the deciding factors to me, in going with the TKO-600 in my '69, though, was the gear set that it comes with (2.87, 1.89, 1.28, 1.00 and .64). With a rear gear of 3.50 and steeper, the 1st gear of most T-5's becomes pretty useless. You're shifting before you get through the intersection.

For the record, I made no modifications to the '69 when I put the Tremec in it.
 

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a well built 8" will hold up just fine.
 

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Be careful with the T-5's first gear and using too much rear gear. A friend of mine has a 92GT with the 3.35 first T-5 and 3.55 rear gears and he is not happy at all with his first gear. He ends up having to shift right after he takes off especially when into the throttle, which pretty much destroys the use of a 5.0's power band.
 

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Discussion Starter #6
thanks for the input.
i think i'll be going with a T5 and keeping my 8" (but with new gears). i will keep you posted.
 
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