I recently purchased a viper conversion for my fbody t56. However, the output shaft I have received has extra length splines as seen in the pictures. Is anyone here familiar with doing the conversion with this kind of shaft? Im told the output shaft is from an Aston Martin.
*Bottom is stock shaft 27 spline
*Top is shortened Aston shaft 30 spline

 

Looks like it uses the ford-style of separate 5, 6 driven gears.

 

The Aston Martin does use a 2 piece 5-6 cluster like the Ford Cobra unit does.

 

So can it be used on a fbody t56? The vendor tells me that it can, and that they substitute the aston martin and viper output shafts regularly. I slid the 5/6 cluster gear on and it looks like it mostly covers the splines.

 

I would be leery considering that any "rock" between the splines and the 5-6 cluster, would be exasperated when 6th gear is engaged under load. If the vendor is telling you it work, I would go with it, but these are questions you should be asking of them..

Why didn't you just do a regular Viper mainshaft that's shortened?

 

I ordered the viper kit/shaft. they sent what you see. When I called the to inquire they told me that the viper shafts were on backorder and that this is what they use.

 

I've used them in the Cobra units when doing a "Viper" spec build but have no personal experience with using them on the 1 piece 5-6 cluster gear.

 

Well, I expressed concern to the vendor and they pretty much agreed to swap it out for me no questions asked. That's what I call customer service. So hopefully Ill have a viper shaft in my hands within a week or two.

 

Looks like they never shortened the shaft, hence the reason it is longer. You need to get 1 3/8" cut off in order for it to be the proper length.
I don't see why the shaft you have in the picture wouldn't work. Just as long as you used the 2-piece 5-6 driven gears, along with the corresponding drive gears on the countershaft extension. Then, like I said, cut it down to size.
I use a 31-spline shaft for this conversion instead of the 30. I'm going to do my best to post some pics of it tomorrow.

 

I guess you can't see it in the pics, but the shaft was shortened....just not to the same length as the f-body shaft.