Author Topic: Powerglide to 8-3/4.. How?  (Read 13161 times)

Offline 1Bad67

  • Newbie
  • *
  • Posts: 12
    • View Profile
  • Your Track: Woodburn
  • Your Vehicle: GTO
Powerglide to 8-3/4.. How?
« on: July 04, 2013, 06:02:05 PM »
I am building a low power (4 cylinder Pontiac, under 300HP) FED. I want to use a shorty powerglide, along with an 8-3/4 rearend. I have most of the rest of the car figured out. I just need help on the Powerglide shorty conversion, and the coupler for the rearend. 

Anyone with dimensions to help me locate the motorplate in front of the rearend?

Where to buy the coupler?

What is the Length of the shorty output shaft? I would like to shorten, and respline the stock output shaft.

Offline denverflatheader

  • Sr. Member
  • ****
  • Posts: 333
    • View Profile
Re: Powerglide to 8-3/4.. How?
« Reply #1 on: July 05, 2013, 08:54:03 AM »
1Bad67 - is that the 1960s 194.5ci tempest four or the later 1980s 4 cyl like 151ci, or another?  Mark Williams Enterprises has various assortment of couplers, they have website located north of Denver.  Strange Engineering makes couplers too, they also have website.  DF

Offline tylercrawford

  • Newbie
  • *
  • Posts: 47
    • View Profile
Re: Powerglide to 8-3/4.. How?
« Reply #2 on: July 05, 2013, 09:00:07 AM »
I bought both the 2-piece output shaft and rear coupler from strange . . .

I highly recommend the 2-piece.  Fitment is great and you can pull it out with the trans and rear in place.

Offline 1Bad67

  • Newbie
  • *
  • Posts: 12
    • View Profile
  • Your Track: Woodburn
  • Your Vehicle: GTO
Re: Powerglide to 8-3/4.. How?
« Reply #3 on: July 05, 2013, 05:05:07 PM »
denverflatheader - it is an old tempest four. It'll get a ram air head, and built up like a mid 60's jr fueler. I want something I can lean on, but still be slow enough to stay out of SFI specs (and costs).

I'll check the Strange Engineering catalog.

Anyone have any dimensions though?

Thanks.

Offline Dolmetsch

  • Sr. Member
  • ****
  • Posts: 339
    • View Profile
  • Your Best Time: dont bother with times anyome (last 4 years) just
  • Your Engine: 225 slant six Dodge . 246 cubes on 94 octane
  • Your Track: Picton Airfield
  • Your Vehicle: The Senior Dragster
Re: Powerglide to 8-3/4.. How?
« Reply #4 on: July 08, 2013, 04:25:17 AM »
Chevy joint fits the 8 3/4 yoke as is. I think the number is 315 G but I could be wrong so double check it.
If it is the big yoke on the 8 3/4 then there are adapter joints (Like the ones to adapt a 400Turbo  yoke to a chevy yoke. ) Also A greek coupler which can be bought or made up from TCS chain /sprocket selection is another alternatice. I only run one joint in mine and after 7 years am more then satisfied wih its perfomance. If running the smaller joint but worried about strength there is a joint either Mroso or Comp Engineering that is solid , no grease holes that takes it up a couple of notches in strength although a normal decent stock joint should be able to handle 300 hp in a rail. I also run that joint in my max wedge clone since it had a 318 originally and the small 8 3/4 yoke. I have serviced it twice in 13 years. Not bad since I ABUSE it unmercifully everytime I drive it.
Don
SR Dragster, because old people need to have fun too!

Offline denverflatheader

  • Sr. Member
  • ****
  • Posts: 333
    • View Profile
Re: Powerglide to 8-3/4.. How?
« Reply #5 on: July 09, 2013, 09:35:13 AM »
1Bad67 -  the tempest four is unusual engine, most have not seen one, so I understand why no responses to your question.   I like Pontiacs, put together exactly what you are asking about back in 2008.  It’s stock rebuilt engine, pg out of 1966 chevy II, mopar 8-3/4, mine is in a red.  Modified the stock pg output shaft to shorty, I bought the aftermarket rear cover to replace the stock pg tail housing.  For dimensions, if you make your own rear cover, that will provide the dimension you need to cut the pg output shaft to make it a shorty trans.  I removed oil filter housing (conflicted with chassis) and made a aluminum plate to cover it and also used that plate to mount new mini-starter.  Due to the thickness of the crank flange, you will have to use a thicker than 1/4  inch mid-motor plate.  Or have a special torque convertor made….
   
The red chassis I bought from 2nd owner in 2003.  The original owner, his friend was there when I picked it up in LA, met and talked to him too.  He said he had Don Long make this chassis for him (no way for me to prove it).  It had a blown sbc in it when I got it, blown as in window in #5 cylinder.  The front end is more like a early fed, everything on chassis nicely done.  The bottom rail front to back has a slight upward arch in it, the wb is 198 and 200 side to side.  Last time I ran it at Speedworld in 2010, it went 14s at just over100 mph.  It’s been sitting for 3 years now…..  don’t have any plans for it, but was fun project to build.   Any questions, please ask.  DF       


Offline 1Bad67

  • Newbie
  • *
  • Posts: 12
    • View Profile
  • Your Track: Woodburn
  • Your Vehicle: GTO
Re: Powerglide to 8-3/4.. How?
« Reply #6 on: July 10, 2013, 12:29:24 PM »
denverflatheader,

I love it. I bet that valve cover caused some confusion. Thanks for the tip on the mid plate thickness. I'll make sure I put the motor and tranny together first, and check that.  14's on a stock motor. 11's on an alcohol injected high compression motor should be possible then.

Thanks,
Eric

Offline denverflatheader

  • Sr. Member
  • ****
  • Posts: 333
    • View Profile
Re: Powerglide to 8-3/4.. How?
« Reply #7 on: July 11, 2013, 12:32:20 PM »
1Bad67 – sure thing, my valve cover’s nothing compared to this valve cover at Speedy Bill’s museum.  I think this valve cover went over 160 mph in the quarter 50+ years ago, one fast single valve cover….

http://www.museumofamericanspeed.com/Pontiac-Tempest-Mickey-Thompson-Supercharged,15450.html

Try out Wallace Racing Calculators, just put in your info and it gives you estimates, very handy tool.  He’s member of this site, runs a Pontiac too.

http://www.wallaceracing.com/Calculators.htm

I put info from my pass and it showed 100hp from my stock engine (at 1335lbs).  For your setup, if you make 200hp, probably into the 11s.  DF



Offline 1Bad67

  • Newbie
  • *
  • Posts: 12
    • View Profile
  • Your Track: Woodburn
  • Your Vehicle: GTO
Re: Powerglide to 8-3/4.. How?
« Reply #8 on: July 12, 2013, 12:33:47 PM »
Yea, I ran the numbers, and if I could get 400hp out of a 400, then 200hp out of the 4 should be doable. It looked like about 11 flat.  Aluminum head, and all the trimmings, and I might get 300hp, which should be good for 10 flat.  That Pontiac Hemi looks great. Just need to find one of those heads laying around somewhere.

Offline janjon

  • Full Member
  • ***
  • Posts: 208
    • View Profile
  • Your Best Time: 5.74/124 1/8
  • Your Engine: SB Chev, gas, 350ish
  • Your Track: Houston Motorsports Park
  • Your Vehicle: '65-ish 150" SBC/Glide FED
Re: Powerglide to 8-3/4.. How?
« Reply #9 on: July 31, 2013, 02:31:11 PM »
Denver, where did you get that radiator? I need one similarly sized for my SBC FED. The one in it lays flat between the frame rails just ahead of the engine and behind the battery. It's looking a bit decrepit and I'm looking to replace.
Thanks,
John
Just keep the same amount of stuff on the right
as there is on the left. Seeing straight ahead is highly overrated....

Offline denverflatheader

  • Sr. Member
  • ****
  • Posts: 333
    • View Profile
Re: Powerglide to 8-3/4.. How?
« Reply #10 on: July 31, 2013, 06:32:30 PM »
John - got the radiator from a friend (Gary) who ran a turbocharged 4 cyl. pinto.  At the time, was one fast pinto in Colorado, I think he took it to Palmdale to run and it broke a piston and ruined engine.  The small radiator worked fine even on 100 degree day, the Pontiac four never overheated on straight water with stock water pump.  For me, I’d only use electric fan on the return road driving back to pits after my run (no need for tow vehicle).  DF