The Woodill Wildfire I'm building has a 322 Buick Nailhead running into a 48 Ford Tranny - using the 48 Ford clutch pedal and linkage. Pressure plate is new Chevy. Problem is pedal effort is EXTREMELY high - I've pressed as hard as I dare - without damaging something - and clutch has not begun to release. Geometry looks good, ie: throwout bearing in proper position and has good travel. Pressure plate is from a clutch shop I use, and they assure me the pressure spec is fairly low, although they are willing to reduce it. Talked to several other "old timers" who said the old Ford linkage was never very good with this type of conversion. My question: am I ever going to be happy with this linkage set-up, or should I go to a swinging pedal and hydraulic clutch ?? Now is an easy time to change !!
last nailhead i put a clutch in i put a hydraulic throw out bearing. if you did this could you still use the ford pedal and mount the clutch master under the floor?
If its a diaphram pressure plate that might be part of the problem,I have found the 3 finger style pressure plates are much easier to push in. I keep hearing the diaphrams are supposed to require less pedal effort but not on the applications I delt with.
It is a diaphram clutch. Who out there is running the old Ford clutch linkage with a "modern" clutch (Chevy, nailhead, etc). Does it work OK ??
First...detail what parts you have, what the diaphragm is from, if you can. Early Ford shaft, collar, and throwout ar larger than most other applications, and if clutch shop is not familiar with the application you might have a diaphragm whose fingers are sized for GM type throwout bearing...this would put the fingers into the hub of the throwout bearing, perhaps even putting them against the sleeve the bearing rides on. You might be able to get a look at what is happening through the little inspection window on the trans. I really think that something fundamental like that is wrong. Stock '48 clutch and linkage do not require great pressur and I think a diaphragm clutch is probably lighter than the original Ford Long. It takes some hunting I think for parts that will fit diaphragm type pressure plate to a Ford throwout. You say Chevy pressure plate...I think that is almost certainly made for a much smaller throwout bearing and everything is just binding as it starts to move.
Thanks, Bruce - I will double check that. It does seem like something like this is wrong, although we checked that as we put it together. The pressure plate is a Chevy , although I thought the throwout bearing was GM also. Disc was custom made. The shop I use does nothing but clutches (and brakes), and are some old guys like us that do a lot of custom work. But, something definately doesn't work !
i bet bruce called it right . diaphragm clutches need throw out bearing to push against the little flat tips, they may not work well pushing on the angled areas. or are "closing in" on the tranny snout, bearing holder, or bearing.
I have the old Ford clutch linkage and a Long style pressure plate on the 283 in my '40. Works great. I used a diaphram clutch on a 331 Hemi I had in a '47 sedan and had nothing but problems with adjustments, too much leg pressure, etc. Switched to a B&B or Long style (I can't remember which, it was a long time ago) and those problems were cured.
If "Chevy" means any Chevy passenger car I have ever see, it has finger spacing much too small to work. Chevy bearing could not go on a Ford snout I don't think. Parts to put a modernish diaphragm in with a Ford trans were covered in Hot Rod Deluxe and I think all was put on here somewhere; probably easiest would be to have the flywheel redrilled for 10" Long and just boltittogether stock.
Just a follow-up. You guys were right - diaphram fingers are contacting the sleeve the throw-out bearing rides on - binding up the system shortly after it starts moving. I think my solution will be to redrill flywheel for a Long pressure plate, as suggested by Bruce. Thanks to all for your help.
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