4spd conversion in a highboy

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Feb 19, 2011 | 03:17 PM

Scolesy8

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From: Ohio

4spd conversion in a highboy

i have a 77 highboy with a TCI C6, and im wanting to convert it to a NP435. i've got the trans and bellhousing for the truck, but the only things im needing now is, Clutch, Flywheel, and Pedal/Linkages. what clutch would you recommend for this application? where can i get a decent flywheel? will a 460 flywheel work? which is best, the original setup or a hydraulic? and finally, is there anyway i can find the pedal linkage set up in a package deal or not? Just some things i need to cover..... i'm running a 408 that is used mainly as a weekend truck to drive, shows, and occasional truck pull.

Feb 19, 2011 | 07:25 PM

Bullitt390

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You have a 351M/400? You'll need the 335 series (351/400) flywheel, not a later externally balanced 460 flywheel or early 429/FE flywheel.

As for linkages, pedal etc you're best bet is the junkyard and snag everything. Also get the pieces for your truck and not the 73-76 pieces as they are slightly different.

An 11.5" long style clutch will hold a tank.

Josh

Feb 19, 2011 | 09:36 PM

Scolesy8

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ok, should i go with the factory linkage set up or do a hydraulic?

Feb 19, 2011 | 09:43 PM

Bullitt390

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Factory linkage is straight bolt in, you'll have to beef up the firewall and fab a bracket for the bellhousing to run hydraulic.

Josh

Feb 19, 2011 | 10:35 PM

Scolesy8

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ok. well that will probably be a little cheaper as well. any thoughts on clutch? Jeffs bronco graveyard sells a LUK clutch kit for $219. any good?

Feb 19, 2011 | 10:40 PM

Bullitt390

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I would go Zoom, McLeod or Ram.

Most NAPA clutches are rebadged Zooms, sometimes cheaper as well. Long style will hold better than diapragm, but diaphragm for all intents and purposes is "easier" on the left leg.

I have a Zoom long style in my truck.

Josh

Feb 19, 2011 | 10:45 PM

Scolesy8

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From: Ohio

so in otherwords i should be checkin out napa? is there any difference between a long and diaphram that would require me to change any parts like bellhousings or stuff?

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Feb 19, 2011 | 11:09 PM

Scolesy8

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but it only needs removed if i were to go with a long style correct?

Feb 19, 2011 | 11:14 PM

#10

Bullitt390

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Quote:

Originally Posted by Scolesy8

but it only needs removed if i were to go with a long style correct?

No the factory set-up is designed with the long style in mind, when installing the diaphragm (i.e. Chevy style clutch) it is possible to iver center the diaphragm "fingers, so some guys remove the return spring to help.

Josh

Feb 19, 2011 | 11:16 PM

#11

Scolesy8

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From: Ohio

ah ok ok i get it now

Feb 21, 2011 | 04:32 PM

#12

Scolesy8

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whats your thoughts on this clutch? from what i was told, since im not putting out some outrageous amount of power, and i still want to drive it, this would be a decent clutch for me. being able to drive it is more important to me than hauling and such.

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