1976 Trans Swap Q

Hi, am wondering about the feasibility of swapping the Muncie out for one of the side loaders from an early eighties Chevy truck. I think GM calls it the NP260 (MY6) which I guess is like the old New Process A833, which is really a 3 speed with Overdrive. The ratios are :3.090 1.670 1.000 0.730 It's basically a stock engine, so with 180 HP am not too concerned about tearing it up. The looks and runs great, but the truth be told, my wife and daughter are the only ones that drive it. If it got better mileage and it was an easy swap, I might go visit the wrecker. So if you can clue me in on splines, yolks, tail shafts and shifter placement,ect, I'd be much obliged, thx

Reply to
Elwood
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There is one other transmission to consider. The T-50. Used in the Monza type cars by Chevy, Olds, Buick and Pontiac. I think they came out in 75 or

  1. Also used in the Chevelle and Olds F-85 and some Vega's. They may have been in some Vettes?? It has a different shift pattern from the newer 5 speeds, First is over and down. Fifth is under fourth. It's a small lightweight unit with a similar OD to the Chrysler and Ford built 4 speeds. For what it's worth, lived with two of the Chrysler built 4 speeds. One in a
77 Volare, one in a 82 GMC pickup. Both failed with the same problem. OD gear starts whining. When you pull it apart fourth gear, the cluster and on the Volare the input shaft and output shaft were shot. Very expensive parts.

Another option would be a Camaro or Mustang T-5. Especially if it was behind a V8. Jeep and others use the same transmission.

Al

Reply to
Big Al

The ratios are :3.090 1.670 1.000 0.730

That first gear is a stump puller. You're going to surprise a BUNCH of people at a few stop light grand prix because you'd have to have a 4.98 rear end with the stock transmission to get the same effective ratio, assuming the Muncie has the 2.20 first gear. It will make 180 hp perform like you have never seen. The step from 1st to 2nd is SO wide you probably won't be happy with performance after you shift though, because it is going to take the engine out of the optimum torque band. The Muncie ratios are closer and keep the engine in a narrower torque/rpm band with shifts. You may want to look at an alternative - swap out the rear end. It may not give you the engine speed reduction you're looking for (e.g. - if you have a 5.55 rear end now, you need to drop to a 2.59 and I'm not sure there ever was one that low - maybe someone else can say for sure).

The transmission swap will work. At the most you're going to have to adapt the mounting bolts for the tranny to the support (I think the bellhousing is the same pattern), tinker with the shifter and linkage, and maybe buy a new custom drive shaft which is no big woof.

Please post your results here if you move forward with the tranny swap. It would be interesting.

Charlie

Reply to
Charlie Funk

'67 & '68 Camaro's with 327 & powerglide came with 2.73's (non-posi) in the rear end. Can't say that I've ever heard of anything less than that.

TomC '90 ZR1

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Crabs

Reply to
Elwood

Hi, thanks for reply. On the highway at 80 mph I know it's over three grand and guzzling gas. A little background may be need for my logic. Last year, the car was pretty much restored as far as paint, interior, steering, and brakes, ect. I had gone lightly through the engine, ball honed it, replaced the cam (with a stock one) and hand lapped the valves. I knew that in California on January 1st of 2005, the car would fall off the rolls of emission standards. So I was all pumped up to spend some cash and make some power. But alas, my fair state changed it's mind and listed the car as a permanent resident as a "test only" vehicle. I was just sick over the whole deal and wanted to just sell it. But my wife and daughter spoke up, they love that car and drive it all over the place. They could care less how much power it has as long as the radio and A/C work. I figured if final went from 1:1 to 0730:1 and could avoid cutting the tunnel up and working too hard it might be a good idea. Thanks.

"Charlie Funk" wrote in message news:dbr78s$e2u$ snipped-for-privacy@news.valueweb.com...

Reply to
Elwood

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waynec

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is what I put in mine NO REGRETSthey have a calculator on site to tell you the rpms after install etc.A COMPLETE DEAL , all the parts are thereask me any questions kickstart

Reply to
Kickstart

Just for ha ha's I wrote down what the C6 does under a lets let her rip moment. At 1,600 RPM in 6th gear it runs 65 MPH, but to push it you got to go back to 5th. You get that same 65 MPH in 5th gear at 2,000 RPM. The 4,000 RPM gets just about 130, 5,000 shows 160 plus, and I run out of balls just over 5,600 RPM with the speedometer (HUD)showing 182. I can be off on the RPM a few, they are a bit harder to read than the digital speedometer. Three times now I've hit the rev limiter and don't like that sound, I'd much rather have a large digital tach in the HUD that the speedometer, or maybe a choice.

Just to jerk you straight while you're diving that fast, two days later coming home I saw 2 deer in less than a mile, one of which crossed the road in front of me. No that's not where I let it loose, I try to pick my roads with a little better chances for the public and myself. It was getting 26.7 MPG before that, I love Kansas. ;-]

Reply to
Dad

Wow, That's sweet, even has the console plate ! thx

Reply to
Elwood

Reply to
Elwood

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