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Well, you now have a good excuse to go with a Tremec TKO 5-speed with OD and a Ford 9" with 3.73 or 3.89 gearing. Both should be bullet proof and then you will have an excuse to build a 500HP stroker engine.
Theres a guy out of Iowa that sells complete Ford 9" rears modified for A body GM cars, with drum brakes, for a little over 2k. Buying an 8.2 rear to rebuild, then the parts to rebuild it, ill be into that rear for over a grand at least. For another grand, I get a new rear, internals and brakes, axle ratio choice, eaton posi, all for about 2 grand. Am I overthinking this?
 

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So for shits and giggles, I decided to open up the muncie that came with my car. I knew it was going to need a rebuild, but I wasnt really counting on this. I will preface this by saying that I know nothing about these transmissions. I was going to get a rebuild kit and book from 5speeds.com and just work my way through it. I couldn't tell what gears were grenaded, but broken chunks of metal in a transmission is never a good sign. Also noticed that there is a hairline crack in one of the mounting ears.




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i bought a new m-22 from a place near chicago, i forget the name, but everything is new including the case, with a steel mid plate. it cost me about 1800 10 yrs ago.

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Theres a guy out of Iowa that sells complete Ford 9" rears modified for A body GM cars, with drum brakes, for a little over 2k. Buying an 8.2 rear to rebuild, then the parts to rebuild it, ill be into that rear for over a grand at least. For another grand, I get a new rear, internals and brakes, axle ratio choice, eaton posi, all for about 2 grand. Am I overthinking this?
No, not over thinking it. BUT, here are a few tips learned when I got mine. The factory sway bar, if you have one, will not fit as the 9" housing is bigger and the bar won't clear it. You can get an aftermarket set-up that will work. I did some fabrication to make one work, but not an easy job as the aftermarket unit is. So more money if you want to add/use a sway bar.

You may have to use a 2-size universal joint - end caps will fit the Pontiac driveshaft and endcaps to fit the 9" depending on the 9" pinion yoke used, 1310, 1330, 1350. I went with the bigger 1350, but will also be using an aftermarket driveshaft. They make conversion U-joints, so not an issue. You just have to get the correct one.

I pieced my 9" together selecting the parts I wanted - which were all new right down to the housing. I went overkill, but only wanted to do it once. You want to know how much HP the rear end will handle. My build should handle 600HP. I am not building a 600HP engine, maybe 450HP, but wanted a little more flexibility should I go more HP in the future. I have the 11" rear drums which I feel is big enough along with my front disc brake conversion. My cost was $2,800. So 2K is a good price.

Here is the 9" using stock control arms just so you can see. Mine is a '68 Lemans. This was just to trial fit it. I used tubular control arms top & bottom, you can see the lowers, and many other modifications not seen in the picture.

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No, not over thinking it. BUT, here are a few tips learned when I got mine. The factory sway bar, if you have one, will not fit as the 9" housing is bigger and the bar won't clear it. You can get an aftermarket set-up that will work. I did some fabrication to make one work, but not an easy job as the aftermarket unit is. So more money if you want to add/use a sway bar.

You may have to use a 2-size universal joint - end caps will fit the Pontiac driveshaft and endcaps to fit the 9" depending on the 9" pinion yoke used, 1310, 1330, 1350. I went with the bigger 1350, but will also be using an aftermarket driveshaft. They make conversion U-joints, so not an issue. You just have to get the correct one.

I pieced my 9" together selecting the parts I wanted - which were all new right down to the housing. I went overkill, but only wanted to do it once. You want to know how much HP the rear end will handle. My build should handle 600HP. I am not building a 600HP engine, maybe 450HP, but wanted a little more flexibility should I go more HP in the future. I have the 11" rear drums which I feel is big enough along with my front disc brake conversion. My cost was $2,800. So 2K is a good price.

Here is the 9" using stock control arms just so you can see. Mine is a '68 Lemans. This was just to trial fit it. I used tubular control arms top & bottom, you can see the lowers, and many other modifications not seen in the picture.

View attachment 145907

Check out that photo real close. Some dumba** installed the brake assembly (ie backing plates) backwards and now has to remove the assemblies and swap them so the e-brake cables will actually work.......................unless I mount and affix a series of pulleys to go up and over the axle, down around the frame ad then back to center so I can use the stock cable coming off the e-brake pedal - then when some newbie who knows nothing about cars asks, "Is that factory?" I can look him straight in the eye and respond sternly (using my age to my advantage), "That's a stupid question," and then walk off. That's how you cover up your mistakes. ;)

See, even I can have a brain fart when you are installing parts in a hurry and think you did a great job. Duh. :rolleyes:
 

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I think it’s a great time to go to 3:36 gears for cruising with a posi and throw the new Muncie in there! But Jim’s idea is also very enticing.
Agreed I dropped my 8.2 from 3.55 to 3.23 and added Posi at same time. Very enjoyable with the Muncie.
 
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