clamping force ?

would you guys say that the TFS streets and the P51's have a better clamping force then the edelbrocks and if so why ?

buy my street heads and you can compare the 2.............

At the expense of being totally in left field, can I take a poke at this one?

I would assume a separate casting's ability to provided more or less "clamping force", and of course the application is the same as well as all other aspects (i.e.: bolts [design & material], applied force), the casting design would play a major role. By design a casting would need to transfer the applied force from the head bolts seat surface area throughout the casting as evenly as possible and onto the block. Thicker decks, added material around the bolt holes and seats as well ample material throughout. More material, less flex. Less flex, the clamping force would increase over a greater area. As we attempt to do with a bolt tightening sequence of sorts.

Just my $0.02!
Dave.

all 10 bolt heads? the heads just set on the block,the bolts do the clampen.

cool40 wrote:all 10 bolt heads? the heads just set on the block,the bolts do the clampen.

so with that being said can we have a large washer,nut to provide more of a clamping force ?

Honestly i wouldn't say there is any if any gain between them all, I may be wrong.

If your that concerned with it step up and go TFS 18 bolt IMO............dont dont sweat it until it actually happens.

bruno wrote:

cool40 wrote:all 10 bolt heads? the heads just set on the block,the bolts do the clampen.

so with that being said can we have a large washer,nut to provide more of a clamping force ?

sure,realy depends on the head.i have some heads with the old prostock plates with all the ex flange cut off and they always looked like a problem wait'n to happen.are you thinken one casting may be better than the other?

.are you thinken one casting may be better than the other?

I thank thats is what he's trying to find out.....maybe

Nick.. are yours not holding.

Just curious what everyone is or has experienced , especially from this big bore stuff ..... just a thought ....

During Last Years EMC dyno testing we tested the P-51 heads with an with out a stud girdle, and only saw 4-6 hp difference with a pretty damn agressive roller, big springs, and 1.8 rockers. Talked with Jon at JOMAR about it and he thought that was pretty low difference compaired to others and commented the castings of Kaase's must be pretty thick or well designed compaired to others they have tested.

That same motor had a cold cranking compression number of 235 and also had no issues with head gaskets on pump gas, but it did rattle a few times while getting agressive with the tune.

So for what thats worth to ya......

here's one example ; friends P51's on the oval track won't hold a head gasket , while the 10 bolt A460's will , both use the same head gasket and ARP studs, comp. ratio is also the same . forgot both A460 blocks

Here is my $0.02...

The clamping force is applied by the bolts and, as mentioned above, the mechanical properties of the bolt can change it. But, the ability of the cylinder head to transfer that force to the deck of the block could theoretically (I don't have enough experience to actually say one way or the other) change how evenly that force is applied.

I'll try explaining with an analogy:

Imagine a 1/4" round rod supported between the edges of two tables. If you push down on the middle of the rod with your finger, it will deflect a given amount. Now, push down on the rod near one of the ends (supported by the table) and it will deflect less (with the same given force). Now, bring a few of your buddies over and each of you push on the rod in a different spot. In my mind, this is what the cylinder head bolts are essentially doing -- a bunch of fingers pushing down on the cylinder head in different spots. Even though aluminum and iron seem very strong, they still deflect. As the cylinder head and deck of the block deflect under the stresses, the 'weaker' areas will transfer some of the force to a 'stronger' areas.

Does that make sense???

Have a good day!
Michael

res0rli9 wrote:Nick.. are yours not holding.

mine are fine ...i have the best gaskets

how much you spray'n Nick?

dfree383 wrote: a pretty damn agressive roller, big springs, and 1.8 rockers. Talked with Jon at JOMAR about it and he thought that was pretty low difference compaired to others and commented the castings of Kaase's must be pretty thick or well designed

Not to promote Kaase's products, although from facts available to me they are very good castings. My comments are of cylinder head structure and design in general, relative to the ability to remain rigid, or be less effected by flex.

As I mentioned in an earlier post, my thoughts as well, as to Dave's comment posted above of Jon @ Jomar. Not to say "I told anyone so", I was just making an uneducated guess! Now with that said, I have learned recently that the structure is a very important part of (in this case) a cylinder heads ability to perform to expectation. Not only with alloy heads but cast iron as well! When a given design is expected to perform far beyond it's original design, faults of the original design soon "rear their ugly heads". What did I learn? A given cast iron cylinder head when expected to perform or performance was unchanged relative to changes which should alter performance, did not produce positive results. Not until the "wink link" of given head was offered added support in the area of deflection. Once the deflecting area was corrected, each change of component's that should offer positive performance, did!

To make my line of B.S. concise, in most applications there is room for improvement, as it can be contained within marketing perimeters.

JMO.
Dave.

There is about 14 lbs between a 18 bolt TFS A460 and a FRPP SCJ/P51 head........which one is the most rigid?

Lem Evans wrote:There is about 14 lbs between a 18 bolt TFS A460 and a FRPP SCJ/P51 head........which one is the most rigid?

We can have a "head bending party" at Bob's ! Round up donor heads, we can place blocks under each end and place the center under the press ram and find Mr. Rigid !

..... .....

Dave.