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The trans I was referring to was the 4L65 Quote:

I don't think there is a need for a racing transmission either but just wondered why the 60 and not the 65

A couple of more details that Kevin mentioned to me:

- Used the rear half of the Packard driveshaft and yoke and the front half of one from a GM truck. This required a professional driveshaft company to weld, fit and balance.

- Trans dip stick had to be relocated (see picture above).

- Throttle position sensor had to be fitted (see picture above).

- Speedo output cable first goes to a computer box and then to the original speedo.

- The shift points and other behaviors are programmable, but Kevin is not going there (I would).

- Gear ratios for the 4L60 are 3.06:1, 1.63:1, 1:1 (direct), 0.70:1 (OD). Compare that to the T-U's 1.82:1, 1.0:1 (IIRC).

- Both T-U and 4L60-E have lock up converters.

Kevin said he is planning on driving his 400 to the PackardInfo meet in Laughlin in Nov, so you can inspect it first hand if you can make it.

Craig

Quote:

Why not a 4L70-E? I don't know, but probably the 4L60-E was chosen because it was available. Certainly any good racing trans shop can upgrade the internals to something that would would take 500lb-ft of torque, if that was your interest and pocketbook.

Craig

THe 60 is probably prefered for space constraints over any larger trans. IIRC JV once said the 700R4 was very difficult fit where as the 200 was easier.

On second thot, HH56 mite have a good point after all. The Packard service manual indicates the V8 has (approx.) 400 lb-ft torque at 2800 rpm.

Quote:

That would be in a drag strip start situation where all the brakes are fully locked and the engine is at full throttle. Ain't gonna happen today. Nowhere near.

Craig

I am sure it was researched to death before the conversion was much more than a glimmer of thought. Was just curious if there was any physical difference that made it not work--just my overkill going into action. You know from my brake project that even if 1/8 thick steel was more than enough, I did 1/4 instead.

Yeah, and not to mention that the T'Ultra is probably only good for about (guessing) 250 ft-lbs. SO the GM 4L460E should be a great improvement.

Some more pictures. Note how original transmission brace was also retro-fitted fro use.

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I tried to get pictures of the shift linkage moving upwards from the transmission, BUT too much stuff in thre and I couldn't get the camera to focus.