Please Help With Driveshaft Installation

[cv2065]

I know that the driveshaft for a 427/T56/IRS combo needs to be externally modified to fit, and not something that is directly done by FFR, but not sure with the Coyote.

[DIBaledo]

I know that the driveshaft for a 427/T56/IRS combo needs to be externally modified to fit, and not something that is directly done by FFR, but not sure with the Coyote.

Ay idea what type of modification. The only thing I could think of that would make a difference is to make the spline shorter.

[cv2065]

Ay idea what type of modification. The only thing I could think of that would make a difference is to make the spline shorter.

Not sure, but I'd give Mike Forte a call. I'm sure that he can help.

[DIBaledo]

Not sure, but I'd give Mike Forte a call. I'm sure that he can help.

Thanks, I’ll call Mike tomorrow.

[edwardb]

Ay idea what type of modification. The only thing I could think of that would make a difference is to make the spline shorter.

Do not cut the spline. Really bad idea. It's designed to have a certain amount of engagement. But shouldn't be necessary and if you're seeing an inch difference, not likely to fit anyway. Bottom line, what you describe is a sign of the wrong driveshaft length. I've done multiple builds and never had trouble getting a proper sized driveshaft installed without taking anything apart. Takes some maneuvering and wonky angles. But should go in. I see multiple builds were guys are taking things apart and eventually get it in. But that's the hard way. Check these instructions from Denny's Driveshafts (an excellent source) and see how the result compares to your driveshaft. https://www.dennysdriveshaft.com/img...iagrams/k.html

[DIBaledo]

Do not cut the spline. Really bad idea. It's designed to have a certain amount of engagement. But shouldn't be necessary and if you're seeing an inch difference, not likely to fit anyway. Bottom line, what you describe is a sign of the wrong driveshaft length. I've done multiple builds and never had trouble getting a proper sized driveshaft installed without taking anything apart. Takes some maneuvering and wonky angles. But should go in. I see multiple builds were guys are taking things apart and eventually get it in. But that's the hard way. Check these instructions from Denny's Driveshafts (an excellent source) and see how the result compares to your driveshaft. https://www.dennysdriveshaft.com/img...iagrams/k.html

Paul,

Thank you very much. After further measuring, the driveshaft from FFR has about 1/16" of clearance. You're right, I don't think that will fit no matter what crazy angles I attack it with. I'll talk to Mike Forte tomorrow, but I think I will need to have a slightly shorter driveshaft made. You identified a link to denny's driveshafts. My engine will put out quite a bit of power and I want a top quality driveshaft to handle it. Do you know anything about their custom built products?

David....

[edwardb]

Paul,

Thank you very much. After further measuring, the driveshaft from FFR has about 1/16" of clearance. You're right, I don't think that will fit no matter what crazy angles I attack it with. I'll talk to Mike Forte tomorrow, but I think I will need to have a slightly shorter driveshaft made. You identified a link to denny's driveshafts. My engine will put out quite a bit of power and I want a top quality driveshaft to handle it. Do you know anything about their custom built products?

David....

I’ve used Denny’s Driveshafts twice. Excellent quality and I’m positive would work for you. There are other choices as some have posted.

[DIBaledo]

Mike Forte has saved the day....again!!! He has developed a specific yoke for this very application that will allow me to use my current driveshaft. I don't know if there is anybody with his background and creativity when it comes to the design of these cars. I don't know what state my build would be in were it not for the experts on this forum who know the intracacies of the build process and Mike Forte who has developed many solutions for some of the shortcomings of the FFR design.

Thanks to all again for your help and advice.

David....