Clutch Issues

[Iron Knight]

This is correct. The naming conventions always go from what "was" to what "is." Starting iwth CASTING numbers, the root number for a flywheel is 6380. The first 164 tooth small block flywheel in the passenger car was the C5AE-A, and it came with an 12-3/8 pressure plate bolt circle patterned for a Long clutch. So the bolt pattern is 2x3 uneven. It could be found in a 66 Bronco with the "big" 11 inch clutch. The C5AE-E flywheel is almost identical, except it is drilled with an 11-3/8 pressure plate pattern, to accomodate the "small" 10 inch clutch. The 10.5 inch clutch is a bastard, and was used in the Hi Po 289 with the small flywheel, small pattern. It's basically an oversized plate stuffed into an 11-3/8 bolt circle long clutch. The disc measures 10-3/8 which causes great confusion 30 years later when the 5.0 gets a 10-3/8 disc. So the 5.0 metric diaphragm clutch is named the 10.4, and the 289 HiPo clutch is named the 10.5. Hot rodders and performance enthusiasts learned quickly that the 10.5 HiPo clutch was a bolt in for any 11-3/8 long pattern flywheel. (157 or 164 tooth) Since they are about 25% stronger, LOTS of them got installed, and the aftermarket sold a bunch of them.

Fast forward to the 70's, and the diaphragm clutch becomes the preferred standard. Since the dia.phragm cover is stamped metal, and the diaphragm fingers are equally spaced, the clutch bolt pattern becomes equally spaced. So now an 11 inch pressure plate with even spacing will not fit a flywheel drilled with unequal spacing. So a whole bunch of new flywheels get made with equal spacing. But the aftermarket is pretty efficient. Someone at LUK figured out that they could build a diaphragm cover with BOTH patterns. (equal space, and Long) Then the replacement cover is universal. A little later on, some Flywheel maker figured out that he could pattern the 164 tooth flywheel for BOTH 12-3/8 patterns and viola! Instant confusion.

So now you can buy a diaphragm pressure plate, and a flywheel that has either or both patterns.

But wait...there's more. By the time the 80's come around, Ford figured out that the 157 tooth, 11-3/8 pattern diaphragm clutch can be made better if it is located by dowels. And the 10.4 metric 5.0 clutch was born. Please don't get me started on the Mopar 10.95 inch clutch.

So, as Paul correctly points out...the diaphragm clutch originally would NOT bolt on to a long pattern flywheel, but it is no longer always the case.

Here's a picture of the Oreilly 164 tooth 50 oz, F150 flywheel, Line: PTQ | Part # NFW1128. ($75.00 with a lifetime guarantee) It has more holes in it than Biden's border…

That's the kind of "occult", hidden information that you won't find anywhere, not even in a mechanical engineering degree, nor in the finest manuals... where'd you find that, by the way? It's very, very interesting...

 

[Iron Knight]

Welcome Iron Knight!
That's a hell of a lot of boat you got there to tow with an EB or any other short wheel base truck!!
I'd be really concerned with brakes and suspension/handling.
Sorry, can't help much with your clutch issue.......someone should chime in on that soon though. Great group here!

Oh yeah, I totally agree with you, the Bronco looks so tiny when infront of the boat, even with those 32 inch tires and 2 inch liftup... I should have gotten a smaller boat there was for sale at the time, but I just fell in love with the Sea Ray... love kept me from thinking clearly, and made me do crazy things, I guess...

 

[Iron Knight]

Hey guys, I'm back... greetings from Chile, that long, thin stripe of land that runs along the Andes mountains, in South America...

Good news, my Bronco is wheeling again, stronger than ever... the problem was in the pressure plate, somehow it got stuck, it was a bit rusty... after the motor mounts and clutch kit (LuK 07-027) replacement and adjustment, my Bronco is back on the road... yeah!!! I also replaced that ugly GM Rochester Quadrajet with hot air choke (I don't think it had the proper CFM's, since it belonged to a bigger engine, Buick 455, if I'm not mistaken, and it started to leak a lot of fuel, even with rebuilding) with a brand new Edelbrock 1406, with electric choke (600 CFM, a lot more proper, and more than enough CFM for the 351W or "Carbureted 5.8L")... damn, this engine is a beast!!! Never put it onto any dyno (there are not many of those dynos around here), to measure power and torque (I don't really know how much power and torque it has, my estimations are 280 HP and 300 lbs.ft, but this is only a guess), but it's a very, very strong engine, I was really surprised when I drove the Bronco for the first time after the engine swap, the change is very noticeable, maybe the good old 289 was too tired, after all... it's not that the 289 is a weak engine, but the difference is truly remarkable, I mean, you can feel it when you push the gas pedal down, all you need is a little wiggle of your right big toe, and... damn. Just a little touch of the gas pedal, and this thing goes crazy, even in 3rd gear (direct drive), no need to downshift at all. Original (factory) cylinder heads, with Speed-Pro Hypereutectic Pistons H336CP, standard diameter 4.000" (compression ratio is 9 and something to 1), everything else is standard. I guess factory roller tappets (F4TE engine block, remember?) and also aftermarket roller tappets make a difference here, maybe I should try to get some more HP's with roller rocker arms as well... the Proform HEI ignition, 10° BTDC, and with the Edelbrock Torker II intake, it pulls like WOW, very little emissions... damn, this thing really pulls... I haven't pulled the boat yet, but, oh my God, this thing is crazy... sometimes I think the tranny (or the differentials) won't stand the pressure, though... perhaps I should strengthen those parts before pulling the boat... yeah, a New Venture NV3550 or NV4500 transmission would be nice; my differentials are 4.11:1, maybe a little more gear ratio might be needed, as well, like 4.55:1... steering and brake system reinforcement, too...

There's a bunch of e-books I think might be very useful for you, especially the long-lost photocopy of the "Chilton's Repair & Tune-Up Guide - Ford Bronco 1966-83", "How To Rebuild Your Small Block Ford" and other guides that no doubt you'll find pretty useful.

Well, hoping you enjoy these books, here they go:

https://drive.google.com/file/d/17dEEYdZokACNmhKt5YiiPboE5a46Oor9/view?usp=sharing

https://drive.google.com/file/d/1cKK2ntq8ugup980WJuDUPHciB9_mNqqC/view?usp=sharing

https://drive.google.com/file/d/1z-gUPdhKjk_16UN550-DbvCfLxEFElnm/view?usp=sharing

https://drive.google.com/file/d/1eUf_-2czryyVTroqsLgOe21wVQgJx1Ly/view?usp=sharing

https://drive.google.com/file/d/10hasPZSZDPcOd7oMqwqcbbJF9AGYq94F/view?usp=sharing

I'm truly grateful, and forever in your debt, for your support and advice... tight hugs to everyone, thank you so much...