# Th 400 Upgrade



## olde-goat (Feb 1, 2009)

I am currently in the process of doing a frame off rotisserie restoration on a 65 GTO convertible. I have had the 389 engine rebuilt along with the tripower. I have a TH 400 from a 69 GP that was just rebuilt. I have a few questions and hopefully some one has done this before and can fill in the blank spots.

-how does the kick down switch get incorporated into the tripower accelertor linkage, or is there another method?

-currently have a 2 speed floor shift with console, are there kits to upgrade to a 3 speed that works with the floor console? I also am assuming that the current rod linkage will have to change to a cable. I have the floor shift from the 67 GTO TH 400, can any of these parts be used?

-I have a drive shaft and yoke from a 67 GTO TH 400 car, and am assuming that this will fit

I have also relocated the transmission mount to accommodate the 400. Do I need a different ebrake cable? Speedo cable change also? Not sure if I have missed anything to complete the conversion.

Any information would be greatly appreciated. Thank you.
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## geeteeohguy (Feb 2, 2008)

The kickdown is electrical, and on a '67, mounts at the accellerator pedal. You'll need that switch. The '65 pedal is different than a '66 on up pedal, it is a floor mount and does not hang. You should be able to fab a bracket to make it work. Only trial and error will help you with the e-brake cable. As for the shifter, I would but a Hurst Dual gate from a '67 in, and I would use the '67 bezel right on top of your '65 console. It will take some fabrication work. for any other info, you need to do research on the internet. All of the info is out there, you just need to hunt it down. A turbo 400 will really make a difference over the old 2 speed superturbine 300. A BIG difference! Good luck.


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## Too Many Projects (Nov 15, 2008)

Ames Performance has a complete conversion kit for what you are doing. It will convert your 2 speed shifter and indicator plate to the 3 speed version. The kit is part number R162M and is $140.00. Since you have the cable and trans brackets I suggest calling them to inquire about just the shifter conversion parts. The kit does not provide the kickdown switch, mount or harness. Their number is 1-800-421-2637. There may be other vendors with this product too such as The Parts Place or Performance Years. I only have the Ames catalog.


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## topfuel67 (Dec 23, 2008)

If you're using the TH400 from a 69 GP it is probably the long shaft 400. The drive shaft from your 67 is most likely for a short shaft 400. Might not be long enough. I was going to put a TH400 in my 65 Tempest that I got from a 65 Catalina. I had the Catalina drive shaft shortened, only to find out the rear end yoke was different! 
One other thing, the TH400 is one of the most inefficient trans out there. It loses over 70HP to turn it. The TH350 is also a 3 speed and is a dirrect fit from the 2 speed, and loses a lot less HP. Unless you're going over 500hp, the TH350 is plenty strong. 100% of everything bolts right up. I converted my 65 to a console shift with a TH350 and am using original 65 console linkage. Works perfect.


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