2005 NB8B currently with a 5 speed with a lovely long short shifter needs a clutch release bearing. 220hp at the flywheel. I have a spare 6 speed gearbox that might as well go in at the same time as it will allow me to add a little power and will have better 2nd and 3rd gear ratios for my local track. I know the 6 speed has a less pleasant change and have lived with that in the past.

Will my 5 speed long short shifter fit on the 6 speed box?

While changing the clutch release bearing, is there anything else worth changing?

 

I don't know the answer to your question, but if you have the 6 speed in hand, why not take the shifter out of the gear box in the car and test fit it in the 6 speed?

 

Pure laziness. And just in case someone already knew the answer.

 

Dave,

the factory 5 speed shifter doesn’t really fit the factory 6 speed box. It bolts in and will select gears but there is so much slop that it makes it not so nice to use,

however depending on what long short shifter you have you may be able to correct that.
Eg I have a miataroadster shifter and they sell replacements cups (about $12 or so) that allow it work in either a 5 speed or a 6 speed without issue.

 

Early 6-speeds had a small bushing that matched the 5-speed. Later 6-speeds used a larger bushing.

 

While the end bushing was the same size the length from the pivot ball to the selector/bushing ball was different, 6sp being shorter. It would ostensibly be possible to space the 5sp shifter up and have it work though.

 

^^^ thank you for the correction. ^^^

 

Yep, that is useful information.
It's also a cheap "short shifter" as well.
Worthwhile to try for a budget build.
I already have a MR shifter for my nice car but for my rat I will try this

 

This thread has useful pics and info on Frankensteining 5/6 speed shifters

https://www.miataturbo.net/suspensio...shifter-61288/