428 vs 360 Flywheel ?

[440sixpack]

I am told my options for a clutch in my '76 highboy with a cast iron bellhousing are limited because of my 428 flywheel.  is this true ?  is it different than the original 360 ? 

 Now it has an 11 "  borg and beck but I was going to go to a diaphragm style.  think I can ?

[My427stang]

The stock clutch for the truck with a 360/390 would be an 11 inch Long style, not Borg and Beck.  I would be very surprised if you had a Borg and Beck now, in fact I have never seen one bolted to a Ford

The odd thing that could be happening is that a 428 wheel could have an 11.5 inch clutch, but even then, they make 12 inch diaphragms that will bolt to the 11.5 inch Ford pattern, you just need to order the correct part

If you have a way to take a picture of what you have now, I am sure we can steer you the right direction

Keep in mind though, you may find a diaphragm real soft with the trucks assist spring.  In my Mustang I run a 12 inch diaphragm and ended up removing the pedal assist spring.  In my F100, I run an 11 inch Long style and replaced all the linkage with Heim joins, it's very easy on the leg

[440sixpack]

it looks exactly like this.   it works fine I just figured since the engine is out this would be a good time for a new clutch. it is an 11" currently  .  unless the 428 flywheel is thicker I cannot imagine why there would be a clearance issue.  I know it's not a diameter issue because it's working fine now.

https://www.summitracing.com/parts/sum-700818/overview/year/1976/make/ford/model/f-250

I know what you're talking about on the spring.  when I put a dual friction in my Challenger  I had to remove the spring under the dash.   

[Rory428]

That photo shows a Long style clutch, like every factory manual transmission FE powered car and truck left the factory with. I believe the only vehicles that used a factory installed Borg & Beck clutch were Chrysler products. Personally, I prefer the Long style clutch over anything else.

[My427stang]

Rory nailed it, that's a long style clutch. 

The only difference between the clutch a 428 would take and a clutch a 390/360 truck would take could be the diameter.  Some 428s took 11.5 inch clutches and some took 11 inch diameter.  However, here is the funny part, some 390s took both sizes too, but the truck would have been an 11 inch

Now, there IS a difference between a 428 flywheel and a 390, but it has nothing to do with thickness, the 428 has an offset balance.  428s are externally balanced by the flywheel where 360/390s are internally.  Using the wrong flywheel will make them shake like hell and come apart

So, if you have a clutch now and it is in your hands, measure the diameter and it's easy for any of us to help.  The Parts guy may have been trying to get you into a factory Ford diaphragm for 1 ton trucks and they are big, they won't bolt to your flywheel and won't fit in the bell

You will likely need to stay with an 11 inch clutch or a very specific 11.5 inch pressure plate made for Fords because of the shallow truck bellhousing (different than a car) however, that doesn't mean you cannot go diaphragm if you want it.  Most of us will think you don't NEED it, but that could be irrelevant. 

Can you post pictures of your exact bellhousing and measure your pressure plate wear surface diameter?

[The Real McCoy]

I did run into a problem when installing a diaphragm style pressure plate on a 428 with a cast iron truck bell housing, part #C5TA 7505 B.  My situation was on a TKO 600 Tremec installation on a 428 in a 63 Galaxie.  The flywheel, 11" pressure plate and clutch disc were new Science Friction brand parts that were part of the TKO 600 kit that I purchased.  I had removed a BW T-10 4 speed and the original 1963 car 390 bell housing.  I needed the truck C5TA 7505 B bell housing to obtain the correct stack up for the TKO 600.

My problem was that the pressure plate contacted the bell housing on the inside at about the 7:00 to 8:00 position, looking at it from the rear, around the area of the clutch fork.  I was able to get a couple bolts started when installing the pressure plate but as soon as I started to turn it to get other pressure plate bolt holes accessible it made contact between the pressure plate and bell housing.  I pulled the bell housing back off and mounted the clutch disc and pressure plate thinking that once the pressure plate that was pulled up snug to the flywheel it would be fine but it still had some interference.  At that point I contacted the vendor that supplied the Science Friction parts with the TKO 600 kit, they had never heard of this issue before.  The interference once the pressure plate was pulled up to the flywheel was very minimal so I ended up grinding the inside of the bell housing to gain some clearance.  I have put a few thousand miles on the car since and everything is fine.  Hind sight is I wish I would have put the original car bell housing back on the engine just to see if that would have had the same problem but didn't think of doing that at the time.  If I do have to pull the clutch in the future I will need to pull the bell housing too as it will still have interference when the pressure plate bolts are backed off.

I'm not saying this will happen on all diaphragm pressure plates but you might want to be aware of the potential problem if you go the diaphragm pressure plate route.

[440sixpack]

 well, Centerforce says it MIGHT be a problem on a 428, but not a 390.  this makes no sense to me if the flywheel is the same thickness.  I have the bellhousing you are talking about.


Maybe I'll just stick with the clutch I have.  it works fine and I don't need anymore problems with this project.

[My427stang]

If it works well, keep it, I wouldn't recommend Centerforce anyway.  Some guys have luck, but I never liked them

[The Real McCoy]

I agree there should be no difference between a 390 and 428 flywheel for this issue.

In my particular case, it is a 428 stroked to with an internally balanced Scat crankshaft so the flywheel was actually a neutral balance 390/427 flywheel, not a 428 external balance flywheel.