Small in/out Wide ratio to big in/out conversion toploader?

[pbf777]

All of this sounds like a lot of work/expense. Why not just swap in a TKO 5 speed and be done with it? Just a suggestion...

    +1   

     But it'll probably be a"TKX" in the end.   

     Scott.

[68stangcjfb]

A 5 speed would be great. But have you priced a TKO lately? Around $2900.00. Plus a shifter, a clutch that fits the input shaft, crossmember? Adds up fast! Also, the TKO 600 has a 2.87 first gear. A TKO 500 has the 3.27 first. A WR top loader has a 2.78. Around $600.00 in parts, my time to rebuild a transmission I already have (I rebuild them myself) and install it in the car, I get better acceleration in first like I want. I drive this car maybe 800 miles year. The expense just isn't worth it to me. I ordered the parts already. When I get it done, I'll let everyone know if it was worth it.

[Royce Peterson]

A 5 speed would be great. But have you priced a TKO lately? Around $2900.00. Plus a shifter, a clutch that fits the input shaft, crossmember? Adds up fast! Also, the TKO 600 has a 2.87 first gear. A TKO 500 has the 3.27 first. A WR top loader has a 2.78. Around $600.00 in parts, my time to rebuild a transmission I already have (I rebuild them myself) and install it in the car, I get better acceleration in first like I want. I drive this car maybe 800 miles year. The expense just isn't worth it to me. I ordered the parts already. When I get it done, I'll let everyone know if it was worth it.

You will like it. I recently installed a David Kee built wide ratio Big In / Big out 4 speed in this '67 Fastback. The car was originally a 4 speed CR / 3.50 open, during the swap we changed it to a 3.00 Detroit Locker. The car was originally a 390 GT, we installed a 462CI stroker made from a 428 block with a SCAT crank.

[TA Coupe]

The price for parts for my TKX conversion from an automatic to manual was $6783.

        Roy

[68stangcjfb]

So, David Kee called me today to discuss my order. My plan was to have the small output tail shaft machined to accept the big output bushing and seal (he said this can be done without compromising strength) but then I asked him about the aluminum 31 spline tail shaft he has listed but had no price online. It is $395.00 with the bushing and seal but he only has a few left (having issues getting them made due to supply lines). I ordered one. Doing a little math, 2.78 X 3.50=9.73.  2.32 X 4.11=9.535. My 1st gear will be better with the 2.78/3.50 gear combo than my 4.11/2.32 combo. I would need a 4.20 rear gear to match that, 2.32 X 4.20=9.74. I can't wait to do this swap! And if I put my 4.11s back in, 4.11 X 2.78=11.425! Now that will be a real tire frier!

[shelbydoug]

A small block combination is 2.32 x 3.89 = 9.02.

With a BB I'd use that as a target. You could do that with a 3.25 rear.


What you really want to duplicate for acceleration would be the "Track Pack" gearing of 4.56 x 2.32. You want to keep the beast as quite in 4th gear as you can.

A 3.50 isn't bad by yesteryear standards but these days you want to stay at 3.00 or lower. You just can't do that with only a 4 speed transmission.



I don't know what condition you transmission is in but I sold two top loaders last year both in the $2,200 range.


Also, I just don't know if an aluminum output shaft is any kind of a good idea with a BB? It likely is going to turn it into a pretzel.

[68stangcjfb]

This is a street car. I'll never put slicks on it. It's just for fun cruising and occasional 100-to-200-mile trips. I don't think I will ever come near the failure point on the aluminum tail shaft.

[68stangcjfb]

Okay. Parts came. Turned an RUG-E3 Mustang/Cougar small in small out wide ratio 4 speed into a big in big out wide ratio 4 speed. Next step is to get it in the car.

[98SVT - was 06GT]

A 5 speed would be great. But have you priced a TKO lately? Around $2900.00. Plus a shifter, a clutch that fits the input shaft, crossmember?

This is late to the party but they have a built in shifter so you only need a lever. Input spline is 26 (GM) on TKO. TKX can come with 10 spline input but you'll still have fitment interference with the top of the tunnel (at least you do on early Mustangs). I paid $1,400 for my heavy duty TKO600 that was converted to a dog box - it's flawless inside they are much harder to break than a toploader unless it's a Jerico.

https://www.jericoperformance.com/4speed_chart.pdf

[68stangcjfb]

If a good used one came along at the right price, I would probably go for it. But for now, I'm going to see how this one turns out.

[shelbydoug]

Yours is an interesting concept. I'm curious to see the final evaluation that you have.

Necessity is the Mother of invention. I have lived that approach myself many times.

I have found that often the results lacked the exultation of the excitement of the path to the solution.

Here's hoping for a fantastic result? 

[pbf777]

        This endeavor of creating a wide-ratio big-block application Top-Loader isn't really new; we had this conversion in the ol' '70 Shelby back in the '70's (w/ 4.56's or 4.88's (depending on the tire) out back); the gear conversion was different as executed, at that time by Liberty Transmissions, but the result is the same.   

        Scott.

[shelbydoug]

        This endeavor of creating a wide-ratio big-block application Top-Loader isn't really new; we had this conversion in the ol' '70 Shelby back in the '70's (w/ 4.56's or 4.88's (depending on the tire) out back); the gear conversion was different as executed, at that time by Liberty Transmissions, but the result is the same.   

        Scott.

The answer always seemed obvious to me. 4 forward speeds isn't enough.

[pbf777]

The answer always seemed obvious to me. 4 forward speeds isn't enough.

      And that's why decades later I utilized 5-speeds in my race car.   

      Scott.

[crossboss]

This is a street car. I'll never put slicks on it. It's just for fun cruising and occasional 100-to-200-mile trips. I don't think I will ever come near the failure point on the aluminum tail shaft.

Don't mean to criticize, but why go through the extra expense and time to convert it if its just a street car?