Must you have a counterbalanced crank to use the V8 pressure plate?

[buyitsmart]

Originally Posted by Milton

Currently I am using a 27 lb flywheel with a counterbalanced crank and a Bratton clutch. The Bratton clutch has the desirable flyweights.

I don't recognize the difference between the two clutches in question. What do you mean by flyweights and non-flyweights???

And then James mentions: "Nobody sells a new, true original V8 pressure plate because it is not available in it's original form. The tractor style is the only type available. "

Again, I don't understand what you mean.

What is the best clutch and pressure plate to purchase?

I am mostly looking for the benefits of a lightened flywheel.

The fact that the V8 style clutch is easier to depress is not what I am most interested in. It may be a side benefit, but I am really looking for the benefit of saving my babbit bearings and having an engine the responds more quickly.

I don't mind that I will have to downshift into 2nd gear when taking corners. I have the Mitchell synchromesh transmission on order as well as their OD so I'm looking forward to shifting gears.

[JoeWay]

Go to Vince Falter's website here and all will be revealed.

In the context of this discussion, I would say that the V8 car clutch on a flywheel lightened to anywhere between about 36-50 lbs would work very well for you.

Joe

[buyitsmart]

Originally Posted by JoeWay

Go to Vince Falter's website here and all will be revealed.

In the context of this discussion, I would say that the V8 car clutch on a flywheel lightened to anywhere between about 36-50 lbs would work very well for you.

Joe

I went to Vince's website and I definitely know what a flywheel is now.

Where the flyweights are on the pressure plate is still a mystery to me. I looked at the pictures of the tractor pressure plate (8N-7563 non-preferred) and the 'weighted' V8 pressure plate (09A-7563 preferred) and cannot tell the difference between them.

Can I have a good local machine shop lighten my current flywheel or does it need to be a special machine shop that understands Model A's???

[Milton]

Originally Posted by buyitsmart

I don't recognize the difference between the two clutches in question. What do you mean by flyweights and non-flyweights???

And then James mentions: "Nobody sells a new, true original V8 pressure plate because it is not available in it's original form. The tractor style is the only type available. "

Again, I don't understand what you mean.

What is the best clutch and pressure plate to purchase?

I am mostly looking for the benefits of a lightened flywheel.

The fact that the V8 style clutch is easier to depress is not what I am most interested in. It may be a side benefit, but I am really looking for the benefit of saving my babbit bearings and having an engine the responds more quickly.

I don't mind that I will have to downshift into 2nd gear when taking corners. I have the Mitchell synchromesh transmission on order as well as their OD so I'm looking forward to shifting gears.

The difference between the two is the passenger car plate has weights (see picture in my previous post) and the tractor plate doesn't. The three weights, one per arm, provide a centrifugal effect and increase the plate pressure on the disk when the rpm increases.

James is skeptical like I am, and doubted the Bratton catalog, like I did.

The tractor style doesn't have the weights and makes up for it with stiffer springs and is harder to operate as a result.

I like the later style because the flywheel is machined flat to use it. That's about 11 pounds gone right there. Another benefit, 6 bolts instead of 12. Three adjustable arms at the throwout bearing. Lighter plate.

The lighter flywheel will help preserve the rear main especially, and a side benefit, but just as important, it will decrease the harmonic vibrations that can destroy a crank.

With the Mitchell syncromesh trans the downshift becomes no big deal. I think that the low/2nd gear ratio increase is the way to go so the big change shifting to high gear is decreased. I have one of those one my list for the future.

By the way, I am using a 27 lb. flywheel with the late pressure plate and both are balanced.

The pic below shows the tractor plate on the left and the passenger car plate on the right. Any more questions, feel free to ask.

[JoeWay]

Originally Posted by buyitsmart

...Can I have a good local machine shop lighten my current flywheel or does it need to be a special machine shop that understands Model A's???

Any good machine shop should be able to do the job. Be sure to specify that they dial in the flywheel using the pilot bearing hole to +-0.0005" or better before taking finish cuts.

The bolt pattern for the 9" clutch is two sets of three holes separated by 32 degrees, on a circle 10.375" diameter. The X-Y co-ordinates are:

X= -1.4299, Y= 4.9865
X= 1.4299, Y= 4.9865
X= 5.0334, Y= -1.2550
X= 3.6035, Y= -3.7316
X= -3.6035, Y= -3.7316
X= -5.0334, Y= -1.2550

You should have it balanced with ring gear installed after machining.

Joe

[Milton]

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Originally Posted by buyitsmart

Where the flyweights are on the pressure plate is still a mystery to me. I looked at the pictures of the tractor pressure plate (8N-7563 non-preferred) and the 'weighted' V8 pressure plate (09A-7563 preferred) and cannot tell the difference between them.

Can I have a good local machine shop lighten my current flywheel or does it need to be a special machine shop that understands Model A's???

Look at the three fingers in the center of the rusty plate. Follow the fingers outward and each one has a small barrel shaped weight at the end opposite the adjusting nut. These three weights are for the centrifugal effect.

If I were you, I would order an already done light wheel from an A vendor. Stipe (Specialty Motor Cams) was mentioned and offers a 25 lb aluminum version for $625 and Dan4Banger has a 27 lb cast iron wheel for $300. The local shops can't really compete and I would be doubtful of their experience.

[James Rogers]

I also have the lightened flywheel for 300$ or 425$ with the plate and disc. I remove the ring which loses 11# and the pressure plate is 6# lighter. That is 17# all together. As for experience, I have done 100 or more and have 35 ready for regrind and balance and 15 ready to go out the door. I have never had a return that was my fault. The ONE return I had was was a bad adjustment by the installer and I still replaced it.

[CarlG]

Originally Posted by James Rogers

...If somebody here knows of a source where these can be purchased ...

http://www.ebay.com/itm/Update-Ford-...item3a6d423376

[JoeWay]

Originally Posted by CarlG

http://www.ebay.com/itm/Update-Ford-...item3a6d423376

The last line in the description is

"New re-manufactured never used product."

Can't be new and never-used if it's a re-man.

I understand James' determination to use new parts, but still I'd rather have a (properly) rebuilt flyweight PP than a tractor PP.

Joe

[JoeWay]

Originally Posted by Milton

...If I were you, I would order an already done light wheel from an A vendor. Stipe (Specialty Motor Cams) was mentioned and offers a 25 lb aluminum version for $625 and Dan4Banger has a 27 lb cast iron wheel for $300. The local shops can't really compete and I would be doubtful of their experience.

Really? You recommend he buy a $625 racing flywheel that is not suited to his application, rather than spend $150 or so having his flywheel machined by a good local shop? Machining flywheels is not rocket science.

James Rogers' $300 flywheel would work better for him than a super-light flywheel.

Joe

[James Rogers]

Originally Posted by CarlG

http://www.ebay.com/itm/Update-Ford-...item3a6d423376

Carl, that's one,I need 35. That is where my dilemma comes in.

[James Rogers]

Originally Posted by JoeWay

The last line in the description is

"New re-manufactured never used product."

Can't be new and never-used if it's a re-man.

I understand James' determination to use new parts, but still I'd rather have a (properly) rebuilt flyweight PP than a tractor PP.

Joe

Thanks Joe, the problem is the reman's are pricey and my customers won't pay the difference. Most think the reman should cost the same as the tractor part. Even the tractor part has gone up 25$ just this year so imagine if you could find the V8 part what it would cost as a reman, 100$?

[CarlG]

Originally Posted by James Rogers

Carl, that's one,I need 35. That is where my dilemma comes in.

Just thought you might be able to read the labels in the ad and determine where this one came from.

[Milton]

Originally Posted by JoeWay

Really? You recommend he buy a $625 racing flywheel that is not suited to his application, rather than spend $150 or so having his flywheel machined by a good local shop? Machining flywheels is not rocket science.

James Rogers' $300 flywheel would work better for him than a super-light flywheel.

Joe

First of all, I didn't recommend anything. I just let buyitsmart know of a couple of sources and, I would have included James had I known he was doing flywheels also. The Dreamwerks website didn't show flywheels, just mighty nice engines. The wheels I mentioned, 25 and 27 lb, will probably be more applicable than say 40 plus pounds. As for cost, around here, it equates to about $10/lb. So he can cut 20 lbs for about $200 and not even have to change the pressure plate. Also with a drivetrain at $4500, six and a quarter isn't that far out, although I would go for the $300 cast iron wheel since a pound of iron is the same as a pound of aluminum where weight is concerned.

Buyitsmart, in an earlier post, indicated that his goal was a lighter flywheel and the pressure plate didn't matter.

"The fact that the V8 style clutch is easier to depress is not what I am most interested in. It may be a side benefit, but I am really looking for the benefit of saving my babbit bearings and having an engine the responds more quickly."

Since he is wanting more engine response, then the lighter the wheel the more responsive the engine. On my first A experience, long ago, I had the wheel cut down 20 lbs. It was noticable but not like my current 27 lb wheel, it allows the cam to express itself. The biggest difference is on hills, stepping on the gas means acceleration. The only drawback is the model A sound is gone. When the key is turned to off the motor stops immediately.

Once more, this is not a recommedation, merely information to aid in his search to buyitsmart. Sorry, I just had to do that.

[buyitsmart]

CarlG
Thanks Carl. I won the auction on Ebay and bought that pressure plate for $85.00

Now I'm going to take my flywheel down to a local machine shop and talk to them about lightening my flywheel using the info that JoeWay provided.

Thanks guys!

[James Rogers]

Originally Posted by Milton

First of all, I didn't recommend anything. I just let buyitsmart know of a couple of sources and, I would have included James had I known he was doing flywheels also. The Dreamwerks website didn't show flywheels, just mighty nice engines. The wheels I mentioned, 25 and 27 lb, will probably be more applicable than say 40 plus pounds. As for cost, around here, it equates to about $10/lb. So he can cut 20 lbs for about $200 and not even have to change the pressure plate. Also with a drivetrain at $4500, six and a quarter isn't that far out, although I would go for the $300 cast iron wheel since a pound of iron is the same as a pound of aluminum where weight is concerned.

Buyitsmart, in an earlier post, indicated that his goal was a lighter flywheel and the pressure plate didn't matter.

"The fact that the V8 style clutch is easier to depress is not what I am most interested in. It may be a side benefit, but I am really looking for the benefit of saving my babbit bearings and having an engine the responds more quickly."

Since he is wanting more engine response, then the lighter the wheel the more responsive the engine. On my first A experience, long ago, I had the wheel cut down 20 lbs. It was noticable but not like my current 27 lb wheel, it allows the cam to express itself. The biggest difference is on hills, stepping on the gas means acceleration. The only drawback is the model A sound is gone. When the key is turned to off the motor stops immediately.

Once more, this is not a recommedation, merely information to aid in his search to buyitsmart. Sorry, I just had to do that.

Find the flywheel ad here.
http://www.model-a-ford-4bangers.com/NewItems.html

[Bob S]

There have been numerous comments in this discussion regarding the benefit of reduced rear main bearing wear by using a lightened flywheel. It's something that seems to be commonly accepted. It doesn't make sense to me. During compression, 50 PSI compression on the nearly 12 square inch number 4 piston results in almost 600 pounds. A load that is carried by the rod bearing and mostly by the rear main. I have no idea what the combustion pressure is, but in another thread, someone said it is 1,000 PSI. That would result in nearly 12,000 pounds load on the bearings. Even if it is only a few hundred PSI, the bearings would have several thousand pounds load. I realize of course that it is only every other stroke that sees this kind of load and that the load isn't that high through the entire stroke, but still, how can a 65 pound flywheel be of any significance by comparison. Think about that poor center main. It sees the load of compression and combustion on every stroke from two pistons, and is a much smaller bearing. If it can handle thousands of pounds nearly continuously, I wouldn't think that big rear main would have much trouble handling that tiny flywheel load in addition to the loads of one piston. It would appear that the flywheel accounts for only 1 or 2 percent of the load.
Am I missing something?

[BRENT in 10-uh-C]

Originally Posted by Bob S

There have been numerous comments in this discussion regarding the benefit of reduced rear main bearing wear by using a lightened flywheel. It's something that seems to be commonly accepted. It doesn't make sense to me. During compression, 50 PSI compression on the nearly 12 square inch number 4 piston results in almost 600 pounds. A load that is carried by the rod bearing and mostly by the rear main. I have no idea what the combustion pressure is, but in another thread, someone said it is 1,000 PSI. That would result in nearly 12,000 pounds load on the bearings. Even if it is only a few hundred PSI, the bearings would have several thousand pounds load. I realize of course that it is only every other stroke that sees this kind of load and that the load isn't that high through the entire stroke, but still, how can a 65 pound flywheel be of any significance by comparison. Think about that poor center main. It sees the load of compression and combustion on every stroke from two pistons, and is a much smaller bearing. If it can handle thousands of pounds nearly continuously, I wouldn't think that big rear main would have much trouble handling that tiny flywheel load in addition to the loads of one piston. It would appear that the flywheel accounts for only 1 or 2 percent of the load.
Am I missing something?

50 psi is the compressed air/gasses but what happens when the spark plug causes that mixture to go "Kablooie"?? That is when it changes. Then factor in torsional deflection of the crank along with possible detonation forces and the stress becomes much greater.

I do however, agree with your thought that a bigger bearing surface is probably not all that critical simply because it shares the "load" of each piston by a percentage due to it being divided over two main bearing surfaces. And one could make a valid argument that the surface area of the connecting rod is much less than the main bearing surface area.

[Kevin in NJ]

The major issue with the bearings is not the overall weight of the flywheel.

It is the combination of imbalance and off center location found on many reground cranks. I was trying to relocate some numbers, but in my brother discussions with the manufacturer of a crank balancer he was told some surprising numbers.
The Chevy 350 flywheels are pretty light in comparison to the A flywheel. The bolts that mount the flywheel on the chevy allow a couple of thou movement. If a flywheel should be mounted hanging off the bench the same way it was hung before being put on the crank balancer. The few thou of play will offset the flywheel causing several hundred pounds of force at RPM.

So The Model A cranks are frequently ground such that the centerline of the crank and the centerline of the flywheel mount are as much as .008" in the cranks my brother and I have measured. Then there can be other issues getting the flywheel out of plane.

So it is likely the most damaging effects you will get are from flywheel imbalances caused by improper machining.

The heavy flywheel might be an asset for the offsetting of the combustion forces. More mass will absorb more energy from the combustion shock. I do not know the math involved, but until I see the math I would not believe anything.

I believe many rear mains that fail could be predicted before the engine is assembled. Poor peening operations that leave the shell loose in the block will guarantee failure in the future. When ever you take an engine apart push on the rear main. If you see a bit of oil ooze out then you know it was not peened properly.

[columbiA]

On my 33-B engine I have a 35 LB flywheel & use stock PP with a spring center disc.I use the longer-by about 3/4"-release lever from a 28 AR multidisc car & I can push the pedal down with my thumb.You have to keep the clutch adjusted with minimal free play or the clutch may drag when first starting out.When I was younger the high pedal pressure didnt bother me.