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Discussion Starter #1
I'm looking for the right 5 speed manual and locker.
Looks like a powertrax lock right will work for about $450. Detroit locker is also an option, but fine print says for open case. Will it work in a factory LS case? $650
5 speeds include T5Z(330lbft) Tremmec 3550(350LBFT) and TKO (500lbft) I'm concerned that the T5 will be so close to max that a little abuse may destroy it. The 3550 is out of production and hard to find so far. And the TKO is huge, expensive, but bulletproof.

Engine is 289 with 302 crank(306CID), BALANCED, aftermarket rods/pistons, World iron heads, dual plane aluminum intake, isky mechanical cam([email protected] .512 lift), long tube headers, 700CFM holley double pumper.
Axle is 8.8, 31 spline, 3.73, traction loc(no longer, clutches worn out).
This will be a drive on Friday, hit the drag strip/autocross as often as possible.... or twice a year whichever is less!
 

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I suspect that you will do just fine with the T5 unless you are running big tires in the rear for a lot more traction.
As for the locker - why not just do the clutches and rebuild it?
 

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I'm building my 5.0 with 10:1 compression, Twisted Wedge heads, balanced, TW Stage 1 cam, Edelbrock Air Gap RPM intake and fuel injection and I'm running the World Class T-5 behind it too. I've got a Versailles 9" with 4:11's in the rear.
Not sure where you are going to find an 8.8 to fit under a '65-'66 though. Everything I have read is they are a bolt in fit for '67 and up, but too wide for our years.
 

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You may want to look into a GForce T5. They are rated at 650ftlb IIRC. I am running one behind my 408w and it has never missed a beat! Also I think you have a little more room in the trans tunnel if you run a T5 compared to a TKO. Good luck!
 

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I installed a used Detroit Locker from ebay when I swapped in my 8.8. Paid about half the new price. When I was looking for a tranny to mate to my supercharged Clevor I wanted a TKO, but again, ebay had a rebuilt 04 Viper T56 for less than the price of a used TKO.
 

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I'm looking for the right 5 speed manual and locker.

- snip -

Engine is 289 with 302 crank(306CID), BALANCED, aftermarket rods/pistons, World iron heads, dual plane aluminum intake, isky mechanical cam([email protected] .512 lift), long tube headers, 700CFM holley double pumper.
Axle is 8.8, 31 spline, 3.73, traction loc(no longer, clutches worn out).
This will be a drive on Friday, hit the drag strip/autocross as often as possible.... or twice a year whichever is less!
What you do depends on how much real streetability matters to you and how much you want to spend.

A WC T-5 is enough transmission for that engine, but the gear spacing is pretty broad. If you wanted a close-ratio gearset there's other options, remember the shallower the helix angle the noisier the box.

Your limited-slip thoughts are exactly opposite what I'd be considering. A Detroit Locker's a solid enough piece for strip use but pretty evil for autocross purposes and less than optimal for an open-track car. I know nothing about the Powertraxx diff but I'd be surprised if it were any better than just rebuilding your Trac-Lok.

More to the point, with an 8.8 you can run a Torsen T-2R or one of the DPI helical diffs. Even a TrueTrac or standard Torsen T-2 is going to be a better piece than a friction diff or a locker. I have a half-tight DPI Black Gold in the Fox, it's not a street car any more but it was livable on the street, at very low speeds you could feel the friction elements unsticking as you started to turn if you really looked for it but it was never objectionable and that car was pretty much gutted of any kind of insulation or isolation anyway.

If you're trying to be competitive at autocrossing read the rule book for whatever organization you want to run with pretty carefully, usually everything that seems like a good idea bumps you into a class where you don't stand a prayer.
 

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Discussion Starter #7 (Edited)
The Detroit locker idea came from hearing that Shelby ran them in GT350Rs. I guess they didn't have gear lockers at the time? The only concern I have with the stock traction lock is hearing they only support 250HP. Will it live long behind 350HP?

I was hoping to find a transmission less than $2000, but the G force 5 at least fits my application and scatter shield and is a little lighter than other options. Maybe go for a T5Z and know G-force can rebuild it if need be? Yes, I'm thinking 245/50/16 in the rear.

Stock 65 axle is 58" tire C-C, found a 8.8 that is 60" C-C. Combining that with wider tires I'm planning small fender flares in the rear.

Competitive, no. Just for fun. Beating a friend I drag along would be a bonus, but not a necessity.
 

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derherr65 and ScottsGT

The 8.8 is 2" wider than the stock rear end for a 65/66 - but that one inch extra on each side can be dealt with pretty easily by selecting a wheel with the right backspacing.

If you don't want to deal with backspacing, you can narrow the axle by grabbing an extra short side axle and having two inches cut out of the press in tube.
 

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t5's are under rated...so long as you don't powershift a t5z will take 400-450 hp.
 

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derherr65 and ScottsGT

The 8.8 is 2" wider than the stock rear end for a 65/66 - but that one inch extra on each side can be dealt with pretty easily by selecting a wheel with the right backspacing.
I've thrown this idea around in my head to see if I could get a set of made for SN95 17X10.5 FR500's to fit on the back of a '66.
 

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The Detroit locker idea came from hearing that Shelby ran them in GT350Rs. I guess they didn't have gear lockers at the time? The only concern I have with the stock traction lock is hearing they only support 250HP. Will it live long behind 350HP?
I don't think you need to worry about the stock trac lock for an Explorer 8.8 with 31-spline axles. That's the rear end they run in the Shelby GT500 with 540 HP, the 03/04 Cobras with 390 (conservative). There are a lot of 03/04 Cobras pushing 650-700 (and some a lot more) running stock 8.8 trac lock diffs. I'm running one with about 500 HP and have no problems, and my car has almost 11K miles on it and the rear-end has a lot more than that. Still leaves 2 strips of rubber when I punch it.

The Explorer rear end is the perfect width for running late-model wheels in a 65-66 (99-04, 05+ have a little too much backspace).
 

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Discussion Starter #12
I'm thinking 245/50/16 on the rear.
Good to know, might just stick with rebuilding the traction lock then.
 

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Discussion Starter #13 (Edited)
Looks like a detroit truetrac runs $450, a Torsen T-2R runs about $650 and a DPI platinum track $850. How do the compare for durability and torque bias?
 

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Discussion Starter #14
TKO600 @ 600lbft runs $2100.
G-force T5 @500lbft runs $2500. Stock case become the weak point.

Is it worth the $400 for easier install and known fit... probably. The reduced torque capacity bothers me some. My current engine won't kill either, but my next engine will be a stroked 351W... 396 or 408. I'd like the trans to live long enough to see, and be able to handle, that combination.
 

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I have a stock T5 in my SN95, running 395RWHP and 410 TQ on my stroked/blown 5.0L and 8.8 rear with 3.55 gears for 6 years now without any problems. Now I don't beat on it, but I do enjoy spirited driving like everyone else.

Like said before, T5's are under rated.
 

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Discussion Starter #16
I'm starting to lean that direction. A street '65 350HP, T5, 8.8, and something else for the track.
 
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