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Transmission Conversion


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Yes. You need an sd22/25 bellhousing. Then you can bolt any Z engine or KA engine trans to it.

 

By Z i mean z22 z24 found in 720s and more not Z car transmissions.

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It won't make it smoother only drop the revs slightly. 

 

Yes. The SD transmission front case has the starter on the left same as the Roadster. Most of the mounting bolt holes line up but may need to be enlarged.

 

 

This is the SD25 front case I brought to Canby years ago for PPeters. The entire 5 speed will also work and is a wide ratio gear set and an over drive of 18.5%, so if 3,000 in 4th a shift to 5th will drop to 2,610. There are other over drive ratios in other transmissions. The early ZX that I'm using is 12.5% and feels like another gear rather than a lower RPM cruise.

 

M3FuNrT.jpg

 

 

 

This is the front bolt pattern for the Roadster transmission

 

2Yz7tK7.jpg

 

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You can also get one from a U20 Roadster that is bolt in. With the frankentranny approach you need to modify the frame for the trans to fit in a Roadster so it will probably be the same for a 411. Also, beware the Roadster 5 speed has a couple known issues such as 5th gear freewheeling if it is the non splined version (which is most) and the main shaft retaining nuts backing off. Easy fixes if the trans is out. Oh, and you need to use the U20 backing place or double up a R16 plate for the Roadster one to fit correctly.

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