A member asked me if I would make a list of items with part numbers needed for doing a 4 speed swap in a 66. This thread has a lot of that info but I figured I'd update here with a bit more comprehensive account of what I've come across doing the last 2 conversions I did. Some of you guys have been invaluable in helping me do those swaps, so please understand I'm just trying to amalgamate all the info here, I'm not saying I pioneered all this!

Two threads here (this one and Mark's 1965 conversion thread cover a lot of this but here I'll try to put more part number info. 

MARK'S THREAD

https://canadianponcho.activeboard.com/t65524339/65-b-body-4-speed-conversion-post/

PILOT BUSHING

There are two different dimensions (O.D.) of pilot bushings to go in the back of the crankshaft. I don't know all the exact years, or engines so you will need to do some measuring if you do this. The pilot bushing that was in an original manual trans engines has an O.D. of 1.093". The bushing you may need to install into the back of the crank if the car was originally an automatic with the smaller hole in the crank is 1.060". Dorman lists the bushing for conversions (the smaller OD, 1.060" bushing) as being a # 690-034.1 The original manual trans bushing (1.093") is a Dorman 14650, or GM 3752487. ***Note, the Dorman 14650 is listed as powdered metal. I hesitate to recommend a metal bushing. They don't appear to last like a bronze bushing does.


I believe at some point all cranks came with the same bore and eliminated this problem but I'm not certain. Dorman says after 1967 there is no need for the special bushing but I'm not convinced that's accurate. I ordered and received Pioneer pilot bushing PB-656-HD off ebay and it's the right one for my crankshaft which is from a 1968 model 427. It's the right size and there's not a hint of the magnet grabbing it.

RELEASE BEARING

Original GM 907963. National/Timken 614018  Beware though that some of the aftermarket clutch kits that fit and work fine are designed differently and while the whole kit works, you can't use the OEM bearing on the aftermarket pressure plate or the other way around.  

CLUTCH KIT

The sky is the limit, endless choices so you'll just have to shop around.

CLUTCH FORK

3860005 GM fork in the only correct fork for this swap. Nothing else will give you the correct linkage geometry unless you fiddle around with the pivot ball height, etc. The fork only came in any 1965-1970 Chevrolet/Canadian Pontiac B body with a manual transmission. 12337938 is the spring/clip that holds the fork to the pivot ball. It's discontinued from GM but I think there's aftermarket pieces out there.

CLUTCH FORK BOOT

14007335 Still available from GM

CLUTCH FORK PIVOT STUD/BALL  

3790556  Still available from GM as of 11-20-2022.  1 13/16" height. Again, only used in applications that use 3860005 clutch fork.

FLYWHEEL

168 TOOTH  Came on 85 or older 427, 396, 350, 327 and in rare cases some 283's and 6 cylinders. Can not be from a 454, 400 small block or 292 6 cylinder (incorrect balancing). The flywheel attaching bolts are 839756 and the pressure plate attaching bolts are 838653.

CAST IRON NOSE STARTER

With this flywheel and the bellhousing you will use, you must use a cast iron starter nose. 1965721 is the original cast iron nose. There are aftermarket iron noses out there if you can't find an original complete starter or iron nose only. This nose uses bolts that are unique, no other Chevy starter bolts will fit. OEM bolts are 3733289. Jobber bolts can be 678-005, 45657 or 6561542.

BELLHOUSING

3872444 3899621 are the two original numbers. In later years another one was cast that works and looks the same, 464697. However, some of those have the pivot ball mounting in the wrong place and won't work as explained on this page ---   https://4speedconversions-com.3dcartstores.com/697.html

BELLHOUSING SHIELD

Still available from GM 3843943

STOCK SHIFTER

Mark's 1965 conversion thread covers this all really well. The shifter body is the same as many other applications, the 3 rods are unique to B body and the handles (depending on year, depending on buckets or bench seat) are also B body only. Same for the boot and carpet trim for the shifter. Make sure you have the B body unique shifter mounting plate as well, OEM number was 3866260. Reproduction mount plates are available. Just google the GM number and you'll find suppliers.

FLOOR HUMP

4 speed hump. Seriously, one of the worst parts of this conversion!     https://canadianponcho.activeboard.com/t64450086/4-speed-floor-hump-for-66-67-b-body-product-review/

SPEEDOMETER CABLE

If you are using a Muncie, you'll need one with the speedo cable going to the passenger side. The correct cable length is right around 68" - 69" which is a bit of a tough find. It takes some poking around online. 3392237 was the original. GMK4030372641 Goodmark cable is a perfect fit but I've had trouble finding them. Again, Mark's thread shows the correct installation for it too. And believe me, it's a lot easier to put it through the correct spot on the firewall if the engine is out, or at minimum do it before installing the bellhousing!