Member: Jetfire1

Member: 62oldsf85

Member: JetfireGuy

XTR Prototype
(courtesy of General Motors)

Member: JimNoel

Member: JimNoel
Custom 1962 Jetfire Wagon

Home Blog Blog Converting to a 4-speed

Converting to a 4-speed

Home Page Forums Discussion Topics – Ask the Experts Converting to a 4-speed

This topic contains 5 replies, has 1 voice, and was last updated by  deucephaeton 7 years, 2 months ago.

Viewing 6 posts - 1 through 6 (of 6 total)
  • Author
  • #7094


    My son is the Jetfire owner and we are converting his car to a 4-speed. We bought all the parts we needed for the driveline from a guy parting a 4-speed Cutlass. Now comes my question. The trans tunnel on the 4-speed Cutlass is different that the trans tunnel on our Automatic. The 4 speed is bigger. It appears the factory put a larger tunnel in and cut the old out. The 4-speed tunnel was spot welded to the old and the original was cut rather crudely and seam sealed. Any input on the subject? :blink:

    Luck is at the intersection of planning and opportunity.



    I have converted two 63 Jetfires. I have just acquired back my first car. I will attach a few photos. The car I have now I just screwed the 4-speed hump in place. The second car I spot-welded it. I could tell the difference between the two cars when driving. If you need any help or information please feel free to give me a call.
    Good luck and keep in touch.
    Ken Dennison



    That’s the parts I have. Spot weld them in is the plan then.
    I’m sure glad I noticed the trans tunnel was different when I bought the 4-speed stuff. Could have been a disaster had I not seen it. Would have been a lot more work to make a piece. 😛

    Luck is at the intersection of planning and opportunity.



    Don’t know if you’re still doing this, I ended up using a 62 Nova shift hump in mine. I didn’t notice the difference in the tunnels until I tried to put the trans in for a dry fit, and then had to cut and weld. It works just fine.



    I made this modification in the same way that kid442 did. I was lucky enough to find an original ’63 Cutlass with the entire 4-speed setup still intact. I got the bellhousing, clutch, flywheel, pedals and clutch release mechanism, transmission and the partial floor pan/transmission tunnel. The factory did cut out the auto. trans. tunnel on the assembly line and welded in a partial stamping to accommodate the trans. shifter. You’ll probably have a hard time finding an original car that was a 4-speed though.



    Actually I found a complete 4-speed drive line out of a wrecked 62 F-85. Bought it from the flywheel to the rear end. Pedal assembley and linkage with trans hump too. Bonus! Thanks for the reply.

    Luck is at the intersection of planning and opportunity.

Viewing 6 posts - 1 through 6 (of 6 total)

You must be logged in to reply to this topic.

New Posts in the Forum

No topics found

Recently Active

Profile picture of Ken Dennison
Profile picture of john-sage
Profile picture of jensenracing77
Profile picture of Mac Kemp
Profile picture of Greg Oakley
Profile picture of Jim Noel
Profile picture of mikepoe59
Profile picture of 62 Cutlass Convert
Profile picture of Nicolas
Profile picture of macf85
Profile picture of joe_padavano
Profile picture of Clint
Profile picture of oakviewf85
Profile picture of whthrse
Profile picture of ray arnold

Who’s Online

There are no users currently online