Author Topic: powerglide to 400 swap  (Read 2230 times)

heatmaker

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powerglide to 400 swap
« on: July 02, 2014, 10:46:22 AM »
Hi guys, brand new to the forum here.. I bought the wife a 67 Camaro with a 327 and a glide.. I swapped out the engine with a 383 stroker, and know Im gonna drop in a 400 behind it.. My question is, will I need to hunt down a new driveshaft for the car? Or will the Powerglide driveshaft fit.

RJ_RS_SS_350

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Re: powerglide to 400 swap
« Reply #1 on: July 02, 2014, 03:33:11 PM »
Hi Heatmaker, Welcome to the site!  I think that there are different length THM400's. I put a THM400 in my 67 I used to have and only had to put a 400 yoke on my PGlide driveshaft (and a new flexplate...and a different starter...and a crossmember...and a shifter). I think I read that it's the tailpiece that makes for a long or short THM400.  Car is long gone, still have the THM400.

hotrod68

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Re: powerglide to 400 swap
« Reply #2 on: July 03, 2014, 06:38:13 AM »
  Welcome!  A Turbo 350 is a lot easier swap than a 400. You can keep your driveshaft and crossmember as the short tailshaft 350 is the same length as a Powerglide. You'll only need to change to a fine-spline transmission yoke. It's virtually a bolt-in. With any 400 you'll have to change the crossmember and the driveshaft will need a bastard u-joint because of the difference in yokes. The 350 uses a cable kickdown instead of the Powerglide mechanical linkage, but all you need there is a kickdown bracket for the cable that any Camaro vendor sells. Depending on your torque converter, you may even be able to use your PG flexplate and starter. You didn't say what shifter you have i.e. column or floor, but that's easily addressed.
   Unless that 383 is a killer, a 350 will live behind it. No question, the 400 is stronger. But it also has higher parasitic drag internally and a less favorable 1-2-3 gear drop than a 350. Hope this helps and good luck!
HotRod'68  1968 SS350 coupe undergoing frame-off resto/rod. 386/350/4.11s
Butternut Yellow    black standard interior

heatmaker

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Re: powerglide to 400 swap
« Reply #3 on: July 03, 2014, 11:10:11 AM »
Thanks guys for the input.  The motor has about 530 horse.. I had the short shaft turbo 400 rebuilt about 3 years ago for a previous project, with a crossmember.   I am trying to keep the interior as stock as possible so I think I am going to buy the conversion kit for the console shifter.  I actually thought that the flexplates were all the same,  what tooth plate will I need for the 400?

hotrod68

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Re: powerglide to 400 swap
« Reply #4 on: July 05, 2014, 08:16:50 AM »
  I think 400s were 168-tooth. But if the converter pattern matches the flexplate it won't really matter.
HotRod'68  1968 SS350 coupe undergoing frame-off resto/rod. 386/350/4.11s
Butternut Yellow    black standard interior

KERR

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Re: powerglide to 400 swap
« Reply #5 on: July 16, 2014, 01:25:42 PM »
if you dont already own the TH400,  look into a 4L80E,  i think they have plug and play shifter boxes for them now.   its a electronic TH400 with OD for the most part...