Manual Conversion

[The_Jeremiah]

I have a 69 cutlass with a 350/TH350. Its a great car, i just dont like automatics, i was just wondering what was the manual transmission that came in these cars, and if it would bolt up to the existing crossmember/driveshaft. and if any other major work would be needed aside from the pedals, and clutch linkage. thanks

[joe_padavano]

Originally Posted by The_Jeremiah

I have a 69 cutlass with a 350/TH350. Its a great car, i just dont like automatics, i was just wondering what was the manual transmission that came in these cars, and if it would bolt up to the existing crossmember/driveshaft. and if any other major work would be needed aside from the pedals, and clutch linkage. thanks

The biggest problem is that Olds usually did not drill the crank for the pilot bearing if the engine was bolted to an automatic from the factory. Your choices are 1) pull the crank and have it machined) or 2) use the conversion bearing sold by various Olds specialty houses. The conversion bearing fits in the existing recess in the AT crank and locates the input shaft of the MT. Unfortunately the recess still isn't deep enough so you will need to trim the input shaft by 1/2" to 3/4".

Beyond that, you'll need the appropriate pedal assemblies, linkages, bellhousing, trans, etc. You'll need the bracket that bolts to the frame to support the Z-bar for the clutch linkage as well as the pivot ball that goes on the block. The factory used Muncie 4 speeds, which will bolt up using the existing crossmember. Unfortunately, restorers have driven the price of good Muncies out of sight. You can also get a conversion kit for a modern 5 spd or 6 spd, but floor pan mods will be required. If you want a factory console, also expect to spend many hundreds of dollars for a good used one.

[1972_442]

Im also looking to do this converison, but with the 455 so how much would it be to get the crank machined? Also what about the reman cranks you can get from places like autozone, you cant just order a crank for the maniual tranny?

[The_Jeremiah]

actually thats a good idea if you can find one from a manual, but you will have to have the block line bored.

[nice72]

Hey, I am new to the site. I found this old thread and have a questiong about the input shaft. First let me tell you about my car. I have a 72 cutlass supreme with 1974 455 with a muncie 4 speed. My father and i coverted from auto to manual about 4 years ago. We fabricated a plate for the swivel ball and had to shorten the z bar since the swivel ball was closer to the frame being treaded into the bracket instead of the engine. The next problem was the pilot bearing...i ended up having a machine shop machine me a pilot bearing to fit in the crank. Alright heres my question...My tranny will pop out of 2nd gear every time you down shift from 3rd to 2nd. The tranny has no problems shifting through the gears when taking off and has no problem down shifting from 4th to 3rd. I have had new synchros put in and it did not change the problem. I am wondering could this problem be due to the fact that i did not shorten the input shaft, or possibly when i had the snychros done they didn't do it right or ripped me off? I would greatly appreciate input on this because before i spend another 500-1000 dollars on the transmission rebuild when that might not be the problem. Also i have a lot of other questions the the 455 and am reading a lot of old threads so hopefully i don't ask questions that have already been asked. Thank you in advance for any input you guys give me.

[gearheads78]

My first thought was syncros but since it was rebuilt with new ones I'm not sure. Did you pull a side cover after it was rebuilt to verify new ones were installed?

[Run to Rund]

A good machine shop can bore the crank .55" deep for the Dorman 690-014 Chevy style bronze bushing.

[1964f-85]

I built a jig out of a piece of plate steel and a piece of thick wall tubing. I cut the plate to match the Muncie to bellhousing bolt pattern, drilled a hole that aligns with the centerline of the crank, welded the tubing at an exact right angle to the steel plate, then, I bolted the bell housing onto the engine, bolted the jig to the bell housing. I then inserted the drill bit into the tubing and drilled the tailshaft to the proper depth to fit the bushing.

I have drilled 7 to 10 engines with this jig (I even did one with the engine installed) I have never had an issue with it.

I just drilled the forged crank on a 68" Toronado 455 (on my Garage Floor, with out disassembling the engine) to put into my 64 F-85 .

[gearheads78]

Sounds like a great idea. Are you using this just to bore deeper for input clearance and still using the adapter bushing?

Originally Posted by 1964f-85

I built a jig out of a piece of plate steel and a piece of thick wall tubing. I cut the plate to match the Muncie to bellhousing bolt pattern, drilled a hole that aligns with the centerline of the crank, welded the tubing at an exact right angle to the steel plate, then, I bolted the bell housing onto the engine, bolted the jig to the bell housing. I then inserted the drill bit into the tubing and drilled the tailshaft to the proper depth to fit the bushing.

I have drilled 7 to 10 engines with this jig (I even did one with the engine installed) I have never had an issue with it.

I just drilled the forged crank on a 68" Toronado 455 (on my Garage Floor, with out disassembling the engine) to put into my 64 F-85 .

[1964f-85]

Actually drilled it for a pilot bushing, I can't recall what size the bit is, but we machined a pilot bushing out of oilite brass to match the bit size.

[nice72]

No i didn't pull the side cover. It was a friend of friend. I guess i shouldn't have trusted it that much. The only reason i'm wondering now weather it is the synchros is because of reading this thread and it saying to shorten the input shaft. I am not concerned with getting another pilot bushing i know that is right cuz i had it machined. I am just wondering about the input shaft because i never heard anybody say to shorten it or that it would be to long untill i read this thread. I mean the car runs great except for down shifting into 2nd. I am also going to be pulling the engine and tranny out to dress up the engine compartment and possibly rebuild my 455. I have been reading a lot of threads on here about 455 rebuilds and heads for the bbo. Unfortunetly i have J heads on the car and am wanting to rebuild the 455 to about 400-425 hp. Thanks for all the input so far and would apperciate any more input on wheather to shorten the input shaft or to bore the crank deeper...or wheather this needs done at all since i have not done it yet and the car runs fine except the downshift problem?