anyone removed 4th and 5th gears?

[92mtxsho]

i know it seems odd but just seeing if any one has done it. and it would save rotating weight as i dont use either gear. i know i have looked at it alot to see it will work with keeping the gear sets on and the bearing seated properly. its confusing though trying to find which is 4th and 5th

 

[lowc]

dont know if this is any help but its been on here for a while and dont know if anyone has them installed may help may not

http://www.shoforum.com/showthread.php?t=100544

 

[rubydist]

iirc, 3rd and 4th are a set, so you wouldn't want to pull those, but I guess you could pull the 5th gear shaft/gearset. the difference in rotating mass is so small you couldn't possibly measure the difference in performance, though.

 

[SHOclub1]

Mike Courtney in MN was the first I heard of, many years ago pulling 5th out of his track car. After, he saw lower tranny temps. 4th isn't going to be something you want to try to do for reasons already stated.

 

[gmorrell]

I removed the whole 5th gear shaft from the SHO powered Pikes Peak hill climb cars that John Wells built some years ago, but these cars used 30" tall tires and didn't need 5th. We just took whole SHO drivetrains and transplanted them into the back of tube frame hill climb chassis. You just need to weld up the 5th slot in the shift gate.

A side benefit is not having the 5th synchro reduces the mechanical drag on the shift fork mechanism when going into reverse, as the 5th/reverse relay lever moves the 5th synchro left to engage 5th gear, and moves it right to engage reverse. This made it a whole lot easier for the hill climb drivers to engage reverse when they needed it quickly.

Removing 4th would require limiting the travel of the 3/4 synchro assembly, otherwise it will over-travel and spit out its guts. I suppose you could block the gate for 4th as well to prevent this.

 

[92mtxsho]

well i think im going to just remove fifth, or just leave it so i dont have to worry, but hey every little bit helps. is fifth gear the gear set that is on the side by its self beside the main shafts? i spun the gear set and i believe with the input shaft facing down and counting up the gears go 1 2 3 reverse 4 then fifth on the side?