Would the 4-spd manual transmission, bell housing, pedals, clutch, etc. from a 1973 GTO swap into a 1970 Cutlass, currently with a 350 and automatic? Would the flywheel from the GTO bolt up to the crank on the '70 olds 350 engine?? I understand the Olds 350 / automatic crankshaft might not be drilled for a pilot shaft bushing. I've also heard there is a conversion bearing available for this?? Any info would be greatly appreciated... Thanks-

 

you could use some of the parts but not all. Bell housing and clutch yes. Flywheel and pedals no.
I here very mixed reviews on the adapter bushing. I am going to be useing one but only temporary until I build the BBO that will have the right crank.

 

As "Rich" said, some but not all. If it was me I would get it all and use what you can. On your 350 olds it is not drilled. It would be very unusal for it to be drilled. I hand drilled my crank about 1/2" in and a little bigger than the input shaft. I used an "Oil lite" brg for the pilot bearing, the diameter of the big hole for the convertor nub.
The pedals may work, but maybe the angles will be a little off. Like I said, get it all and use what ever. Be sure to get the rods and "Z"-bar and all brkts.
You might check "Year One" I think they offer a kit or at least parts that you need.

Gene

 

Thank you for the replies. What are my options for the flywheel - would it have to come from an Olds 350 crank? Can the crank be drilled while still in the engine, or would it have to be removed?

 

Any olds stick flywheel from 68 to 76. No matter small or big block. Often you can find one from a jet boat. It never had a clutch on it so you will have a virgin surface. A light machine surface and you are set.

Gene

 

If you use the conversion bearing, you only need to drill a clearance hole in the crank. This is difficult but can be done with the crank in the engine. If you plan to have the crank machined for a stock pilot bearing, this needs to be done by a competent machine shop and the crank must come out.

 

Do you know if the pedals out of this '73 GTO will be correct? By the way, the donor GTO is a complete car for sale, although it's body is totally shot.

 

My parts book shows the 73-77 clutch pedal as a different number from the 68-72 pedals.

 

One more question on the 1973 GTO: will the rear axle from this car drop into my '70 Cutlass? Thanks!

 

It will drop into the trunk. Otherwise, no. The 73-77 cars are completely different from the 64-72 cars.

 

Thank you for the reply. The reason I asked that is because currently my Cutlass has a 2.56 rear gear, and I do not think that will work very well with the manual transmission, particularly in first gear from a dead stop. What do you think? Didn't the manual transmission cars have rear gears that were numerically larger than with an automatic?? Thanks, J-

 

You are correct to be concerned. Without the torque multiplication of a torque converter, the car will be a dog off the line and will require significant clutch slippage. Of course it all depends on what first gear is in the manual trans. A close ratio Muncie (2.20:1 first gear) will be especially bad.

 

I converted my 72 cutlass from 350/350 to a 71 455 out of a Vista Cruiser and a muncie out of a 66 GTO. The pedals I used came out of a 73 GTO. The pedals swap out in an hour or so, don't worry about using the stamped steel part that bolts under the dash, just remove the cross shaft, take the pedals, clutch rod, bushings clips etc. Remove your existing single pedal and these will bolt right in place. Don't for get the z bar and the bolt on frame clip that holds it.
As for drilling the crank, we built a jig out of a piece of steel tube with a ID the same as the hole we wanted to drill in the crank and welded it at a right angle on a piece of plate steel that bolts to the bellhousing. This must be indexed to align with the divet in the end of the crank shaft. Drill just deep enough to seat the bushing. I have done this 12 times, in the car and out and I have never had an issue.
Everything else is after that is a breeze.

There is a guy in town parting out a 71 442, 455/4 speed, he has all the necessary parts (at a price)

Scott Renzenbrink

 

Several years ago I purchased a 1968 Cutlass with a close ratio 4 speed. It had a 3.08 rear end and it was hard to come off the line without slipping the clutch bad. I replaced it with a 3.31 and that was very comfortable. The paperwork on my 1970 shows it had a 3.23 from the factory but that had been changed before I got the car. So my suggestion would be to look for a 3.23 to 3.42 ratio for all around driveability. You can go lower, but at highway speeds the 3.91's rev the engine pretty high and suck the gas even more, but they are responsive and fun to drive. So what you plan to use the car for should be a consideration. A daily driver stay with the 3.23-3.42 ratios. For just a fun car around town with occasional highway trips the 3.73 and 3.91 are a kick in the pants. My 2 cents. John