55.2-59 1959 GMC fleet - 250 I6 - NV3500 - 12 bolt 3.73

[dennislbrooks]

OK, has anyone retained the clutch floor pedal and put a clutch master cylinder on the firewall? Will have to be a perpendicular mount and the pushrod will have to be mounted to the in cab pedal arm. I have a an NV3500 and plan -- have not checked yet - on using a block mounted starter - 153 tooth flywheel - 10.5 clutch. It appears the NV3500 is a coarse 10 spline input like the m20 and I have not verified but looks like the output shaft is 27 spline also.

Engine has been fitted and I used an m20 for mounting. It appears I can use the original driveshaft with a 27 spline long yoke. The NV3500 may be 1/2 to one inch shorter. I can still move my front and rear mounts for the I6 and tranny.

I may be able to mount the clutch master cylinder to the frame and use the existing clutch pivot arm on the engine side. Would have to get my angles correct. Will cost me $90 to find out.

Any info and/or anticipated problems are appreciated.

[dsraven]

let me get this straight.
you want to use the stock clutch pedal that goes through the floor and pivots on the frame mounted bracket but use a master cylinder that is mounted to the firewall? seems like a lot of linkage and fulcrums etc would be required plus the risk of the cab moving over twists etc and that affecting freeplay etc. a frame mounted master may be a better option if you have enough room to make it work since the pedal, linkage and master cylinder would all be frame mounted. I would suggest to find a clutch master cylinder and slave cylinder that give the correct amount of travel for the clutch and fork length being used, then match up the linkage geometry from there to ensure you get a full master cylinder "stroke" capability to match up to a full, or almost full (for built in safety), pedal stroke. a master cylinder with a remote reservoir would be something to look for as well.

[mongocanfly]

I agree...that would be a nitemare of linkages to make it happen..you can get a wilwood clutch master with remote reservoir...then you can mount it under the floorboard and keep the factory pedal..and mount the reservoir wherever you want....