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Drivetrain => Transmissions => Topic started by: Jim on March 03, 2023, 05:16:45 PM

Title: Sp400 in a gs
Post by: Jim on March 03, 2023, 05:16:45 PM

Getting towards  spring ,almost  time to dig out the sp400  I bought ran good 20 years ago so I need a overhaul kit  what brand are people using ?also how much do I have to shorten the drive shaft.i take it I can just move  the transmission mount back?  Jim

Title: Re: Sp400 in a gs
Post by: GS66 on March 03, 2023, 08:33:57 PM

I have a Turbo 400 in one of the 66?s. I am planning to install a Gear Vendors unit behind it. Also replacing one of the ST300?s with a 200-4R. We need overdrive for interstates and long trips.

Title: Re: Sp400 in a gs
Post by: Jim on March 03, 2023, 08:53:17 PM

Yes ,our last 3 cars all had overdrive, 68 elcamino ss396 700r4 ,42 buick 430 200r4 ,39 lasalle 350 700r4 they were all streetrods the 65 is so stock I really hate to change it..thinking of the martin adapter for the 200r4.Jim

Title: Re: Sp400 in a gs
Post by: WkillGS on March 04, 2023, 08:10:13 AM

The ST400 rear mount on the tail is further back, so crossmember needs to be moved back. The 65-6 frame bracket is too far forward to fit it. You'll have to fab an extension, it could be as simple as bolting/welding on a piece of angle iron to the frame, or cutting and extending or moving the original back.

The 65-6 console shifter needs some mods as well. The lever under the floor will hit the ST400 tail. You can make clearance by bending/grinding the original, or use a cable conversion from Shiftworks.
The 67 GS shifter (with ST400) passes thru the floor in a different location, it doesn't use the same floor opening.

Use the torque converter from the 2 speed GS, it's a smaller diameter and has a higher stall speed.

For the rebuild kit, I had a Red Eagle and Kolene kit bookmarked, it was likely recommended by someone somewhere! :dontknow:

Title: Re: Sp400 in a gs
Post by: Jim on March 04, 2023, 10:06:59 AM

Thanks ,really don't want to go to napa  or wherever and get a generic kit if there us a good one out there getting old,.its not as much fun crawling under the car as it use to.for some reason the transmission seams to weight more than they did 20 years ago.jim

Title: Re: Sp400 in a gs
Post by: telriv on March 04, 2023, 11:11:25 AM

Ain't that the truth!!!!

Tom T.

Title: Re: Sp400 in a gs
Post by: kcombs on March 04, 2023, 11:20:38 AM

And workers offer to help me with heavier things, I don’t understand! I’m only 74 years old (almost 75).

Title: Re: Sp400 in a gs
Post by: telriv on March 04, 2023, 11:24:03 AM

So what's that got to do with it.
I'll be 77 in June.

Tom T.

Title: Re: Sp400 in a gs
Post by: kcombs on March 04, 2023, 01:11:10 PM

Quote from: telriv on March 04, 2023, 11:24:03 AM

So what's that got to do with it.
I'll be 77 in June.

Tom T.

That makes a me a young’en. ????
Kurt

Title: Re: Sp400 in a gs
Post by: kcombs on March 04, 2023, 01:12:00 PM

Oops, sorry, back to transmissions now.

Title: Re: Sp400 in a gs
Post by: Jim on March 04, 2023, 02:17:01 PM

Only 73