I found this post by Oldsmobile Joe on gbodyforum.com and was hoping someone can confirm his information for me.

"olds bell housing are all the same, they are a BOP housing with a dual transmission bolt pattern. the first pattern is for traditional muncie/saginaw/t5. the second pattern is for the ford HD 3speed trans that was offered back in the 60's. both of my t50 equipped cutlasses have this bell housing."

I am trying to make a transmission selection for a 260-455 swap. Five speed OD was the first choice but I really do not want to cut the floor and I am still not sure if it would be an issue in the 73-77 cars. Maybe an M-20 to go with the current 2.73 rear end? This will be a stock 455 cruiser.

Thanks in advance

 

many bell housings have the dual pattern for muncie or ford, not all have it

 

Do you know it the T50 and Muncies are the same? Hoping to reuse the original for now.

 

it lookslike its the same as the muncie

https://classicoldsmobile.com/forums...ission-110340/

heres a pic i took off the internet of a dual pattern BH ford pattern in blue muncie in orange. I think if you look at your bell in the car you should be able to tellif it has the ford pattern on it

 

Thank you

 

The T50 and even the original GM T5s all use the Muncie bolt pattern to the bell. What I don't know is if the diameter of the pilot on the bearing retainer that really locates the trans in the bell is the same. That's really more important than the bolt pattern - you can always drill more holes. It's the bearing retainer that locates it.

 

You are talking the pilot bearing in the crank, correct? Not the throw out or fork pivot.

 

Neither. I'm talking about the input shaft bearing retainer on the front on the trans that fits into the large hole in the bellhousing. THAT'S what locates concentricity of the trans to the engine.

 

Got it

 

Aside from the obvious engine to trans alignment concerns, the g-body bells have an oddly shaped throw out bearing fork which positions the pivot ball lower in the bell housing. When I converted my ‘82 Regal in ‘99, I used a steel Lakewood scattershield and had to fill, drill and machine the necessary holes to accommodate everything. The TKO five speed held up just fine with a GN 8.5” ring and is almost certainly the most impressive upgrade I had ever done to the car. I’m sure that I would have been lucky to have gotten half as much when I sold it, had it still been a TH350.

 

The OP has a 1977 A-body with the factory 260/T50 combo. It's the normal A-body bell.

 

Whoops, I clearly missed that!🙄

 

Moving forward on the tremec install. I have been talking to joe at https://dederichsmotorsports.com/ and he believes there are two different bell housings used with the T50. One was used for the 4/6 cylinder engines and one for the V8. He believes the V8 bell housing has the correct opening and will work with the TKX. We will find out soon.

 

It will work just fine. You might need to create a relief or opening to accommodate the shifter housing on the TKX. Otherwise it’s pretty much a straight shot. You are going to LOVE this investment!!👍

 

That is good news. Being that the car is a 442 it has bucket seats and no console so hopefully it will be easy if needed. When I did have the transmission out of this car the hole for the shifter looked like someone cut it
with a jig saw on the line.

 

Hoping to use the OE bell housing and Z bar set up. I think it might be a fairly easy swap. The only concerns are crossmember, shifter/location and driveshaft.

 

Crossmember will likely be shifted one hole forward on the frame.. The driveshaft replacement is a given both for additional length as well as marrying a 31 spline Ford inspired yoke to your GM drivetrain.. Not difficult, not overly expensive considering the price point of the gearbox.. I used a standard 1350 joint on the front and the factory 3RL joint on the rear on a 3” tube. No special adapters, 3/4 ton truck grade. Super dumb,,…. Super FUN!!🤩

 

Driveshaft is a no brainer. It should go smooth but I am hoping I am not jinxing myself.