Hey all,

Newbie here. Been around cars a long time, 442's have been a favorite for a long time as well. Looking forward to learning.

Anyway, my question comes from a potential purchase I'm looking at. It's a 64 Jetstar 88 sedan, it originally was a 330, owner swapped it to a 425, edelbrock goodies and such. It really is mint, 19k original miles, mint original interior and it's pretty cheap (asking 4500).

My question is this. I do not know exactly which trans is in the car, but I'd prefer to buy a 'toy' that's got a manual. So, I'm wondering if it's even possible, if so how do I do it and what parts to use, to swap a 4spd into a jetstar 88 with a 425 in it.

Do the parts from the cutlass/442 interchange? I've found a place that has a manual conversion kit for $289 for everything minus clutch and trans.

So, can it be done? And with what parts?

 

The 1964 J88 has a lot of one-year-only parts. The automatic is a two speed ST300 (not a Powerglide), also called a Jetaway by Olds.

A four speed manual was factory optional, but the clutch parts are unique to the 64 J88 and are nearly unobtainium today. The A-body bellhousing and flywheel will work (assuming the flywheel is for a 1964-67 Olds motor, since the crank flange bolt pattern is different from on the 68-90 motors). You are unlikely to find a factory clutch/brake pedal assembly, so plan on adapting aftermarket pedals if you go this way. Similarly, the clutch equalizer parts are virtually unavailable, so plan on using an aftermarket hydraulic clutch assembly.

Of course, your biggest problem is that Olds motors that did not come with a manual trans from the factory usually do not have the crank drilled for the input shaft pilot bearing.

 

thanks for that info. I should have been a bit more specific; it's a 64 that has had a '66 425 out of a Delta transplanted into it, dunno if that makes any difference.

Outside of that though, it still seems from your post that it's nearly impossible. Anyone had any luck transplanting something like an auto with a manual valve body into the thing? I guess I'm just worried about getting bored with the damn thing considering my daily is an automatic and I really miss having a stick shift.

 

OK, I missed the fact that the engine had already been swapped. The conversion is not impossible, as others have done it, but I wanted to point out that you are unlikely to readily find the parts that allow it to be a bolt-in. Street rod parts are available to do this, but at a price and requiring some fabrication. If the crank in the 425 is not drilled, you can either pull the crank and have the hole machined (the better solution, if far more work) or you can use one of the conversion pilot bearings that are available from various Olds specialty houses.

You can manually shift a TH400 in stock form. That's all Hurst did with the dual gate shifter. You can also build a TH400 with a manual valve body - those are readily available in the aftermarket.

 

So, Joe, what's the good news?

 

ah ok, so the turbo 400 then is a pretty common swap from the jetaway? What other autos are commonly swapped?

The car does have a column shift of course. I'd be looking for the minimal amount of fabrication necessary as I don't have many tools nor a full garage.

 

The auto shift is by far the easier swap. Find a good BOP 3 speed (TH400 or TH350) trans and install a trans-go shift kit that has the manual shift option. I'm not familiar with a Jetstar so I have no idea what would be involved in adapting the column shifter to a later trans, I don't think it would be that big a deal. Either trans will make a HUGE improvement in acceleration due to the much lower first gear, with no loss of economy.

 

You shouldn't have any issues with linkage, everything will almost line up. A T400 will require driveshaft mods, and T350 will bolt right in. I'd recommend a new torque convertor 1 level over stock. The T400 will probably also require some emergancy brake cable mods. The T350 requires a cable for kickdown and a T400 is electrical.

 

Ok, so I just spoke to the owner and apparently the 425 is from a 66 dynamic 88. The original 2 speed is in the car, and unfortunately today's shitty otherwise I'd be running over there to look at it.

Does the fact that it's out of a dynamic make any difference?

 

Nope, other than it's probably a small valve 9.0:1 CR motor.

 

Find a BOP TH 400 in the junkyar and put a filter and manual valve body in it. You won't be disappointed. Actually, it is a scientifically proven fact that the TH 400 is the BEST automatic transmission GM ever built (for the record the WORST is the Slim Jim Rotohydramatic).

 

Nope, sorry. The worst is the RotoHydramatic 5 in the 61-63 F-85s.

 

Much, much worse then either of those is Turboglide and Flightpitch.