FE Head gaskets

[frnkeore]

I've only been on this form, a little over a year. I hear of recommended head gaskets for this or that but, I haven't seen a thread on how and why, to select one for a particular application. Besides their sealing ability, they can make a fair difference in CR and especially quench. What gaskets are the best for aluminum and cast iron heads?

I compiled a list of commonly available gaskets, with their cc capacity. I found two problems, the first was the lack of a cc capacity for the Fel Pro 8554PT. It uses the original Ford shape and I can't compute it's capacity. Does anyone have that info? The second is the Edelbrock, it, like all the others has a round bore, by it's pictures but, it's said to be 9.9cc. Computing it's dimension, it is actually 9.17cc and it's been said, on this forum, that it doesn't compress to .038. Does anyone have any hard numbers on it? I verified the the listed capacity of all on this list, with the noted acceptations.

The 8554 seems to have conflicting compressed thickness, some on here, say .053 and another source says .050 +/- .0015. I would say, that the actual head bolt torque could account for that. By that, the I mean, the accuracy of the torque wrench and what the bolts are oiled with, along with how well the block and bolt threads are preped.

 Do the MLS have a more reliable compressed thickness and has anyone used the Mahle/Clevite 3389?

Here's my list, feel free to add to this list and comment on any of them, in actual application:

Mr. Gasket 5790G .038 x 4.400 Graphite 9.468cc
Mr Gasket 3256G; MLS .040" x 4.400" 9.967cc
Mr Gasket 3255G MLS .040" x 4.325" 9.630cc
Edelbrock 7337 .038 x 4.33 9.900cc / 9.170
Fel-Pro 1020 .041" x 4.400" 10.100cc
Fel-Pro 8554 PT .051 x 4.330 not round 4.33 x 4.57 est 12.70cc
Fel-Pro 8045 PT .051 x 4.200 not round 11.86cc
Fel-pro 9061 PT .061 x 4.200 not round 14.20cc
SCE M343239   .039" x 4.325" 9.389cc
Cometic Gaskets C5835-027 .027 x 4.25 6.277cc
Cometic Gaskets C5834-030 .030 x 4.165 6.698cc
Cometic Gaskets C5835-040 .040 x 4.25 9.299cc
Cometic Gaskets C5840-051 .051 x 4.44 12.708cc
Trick Flow TFS-56494080-040 .040 x 4.08 8.570cc
Trick Flow TFS-56494165-040 .040 x 4.165 8.931cc
Clevite 3389 .050 x 4.33 12.065cc

[blykins]

A couple of random thoughts here:

1.  Bore size doesn't affect the compression ratio like thickness.

2.  I prefer the gasket bore to be close to the cylinder bore, but not close enough so that the fire ring gets into the cylinder when hot.

3.  Aluminum heads don't need a special gasket. 

4.  Some aluminum blocks need a special gasket as the fire ring matches up to the sleeve and helps if the sleeve drops slightly below deck.  A 1020 fits a lot of aftermarket aluminum blocks well.

5.  An 8554 gasket works very well in a lot of applications.  When I use them I will let the piston hang out .010".  They compress to about .050-.051" here. 

6.  Gasket thickness depends on quench distance. 

In most cases, I will either run an 8554, 1020, or a Cometic.  I do have some new SCE MLS gaskets in here that I plan to use soon.  They are a 4.325" and 4.400" bore, with .039" thicknesses.  Those seem to be good combinations in dimensions.  The MLS gaskets work well with boost and also are offered in many thicknesses for use with aluminum rods, etc.  They will be more reliable in thicknesses.  There are a lot more Cometic gaskets offered than what you have shown.

[frnkeore]

Yes, there are a LOT more head gaskets, I kinda stopped at the ~ $100 each mark. I was looking for a affordable .060

I also forgot to ask about the original Ford, steel shim gaskets. you can still find them on Ebay and swap meets. Does anyone know what the diameter and cc capacity is of those? I used them when I was a mechanic and don't remember any issues with them. We had blown head gaskets but, that was only after a sever over heat.

The 8554 is used a lot and I've got some to use. I thought their capacity would be a quick answer. As a guess, I would say ~ 11.5cc?

[blykins]

Yes, there are a LOT more head gaskets, I kinda stopped at the ~ $100 each mark. I was looking for a affordable .060

I also forgot to ask about the original Ford, steel shim gaskets. you can still find them on Ebay and swap meets. Does anyone know what the diameter and cc capacity is of those? I used them when I was a mechanic and don't remember any issues with them. We had blown head gaskets but, that was only after a sever over heat.

The 8554 is used a lot and I've got some to use. I thought their capacity would be a quick answer. As a guess, I would say ~ 11.5cc?

Cometic will have the .060" gaskets, but I suppose affordable is relative.  They will be close to $180 a pair.

You're probably ballpark on the 8554.   I would use a 4.325-4.330 bore size with a .050" compressed thickness as data.  The bores are not round, but bore size doesn't make a dent in the compression ratio like thickness does.   Holding the thickness constant, changing the volume from 4.320-4.350" only decreases the compression ratio by .02 points.

[427John]

Yes, there are a LOT more head gaskets, I kinda stopped at the ~ $100 each mark. I was looking for a affordable .060

I also forgot to ask about the original Ford, steel shim gaskets. you can still find them on Ebay and swap meets. Does anyone know what the diameter and cc capacity is of those? I used them when I was a mechanic and don't remember any issues with them. We had blown head gaskets but, that was only after a sever over heat.

The 8554 is used a lot and I've got some to use. I thought their capacity would be a quick answer. As a guess, I would say ~ 11.5cc?

The Ford gaskets as best I can remember .030 for the B9AE gaskets don't know what the gasket bore was but were to be used up to 4.13 bore blocks not on the 4.23 bore 427's there was a similar gasket with a C2AE number that was .015 available for the 406's,when the 427 came out a new gasket was made in 2 thickness both with C3AE numbers with different suffixes that I can't remember 1 was .030 which was typically the 1 installed at the factory the other was .015 and was usually sold over the counter,I don't know what the bore dimension is on that one either I don't think it was round anyway,I know the earlier ones weren't.

[My427stang]

Frank, I am close to Brent, I use .053/4.36 for the 8554

When you start looking at small bore gaskets be sure to look at chamber dimensions too, very few, if any factory iron chambers are as small as a 390 bore. Easy to get a gasket with areas without full fire ring compression

[Posi67]

Cometic fan here..  Only expensive for the initial purchase but can be reused. Anyone know how many times? I know of some numbers that would be called BS however I'm not talking about longevity here. 1020's a good all round gasket.

[blykins]

Cometic fan here..  Only expensive for the initial purchase but can be reused. Anyone know how many times? I know of some numbers that would be called BS however I'm not talking about longevity here. 1020's a good all round gasket.

I will reuse 1-2 more times.  After the initial installation and tear-down, I'll spray with copper coat and throw on again.

[frnkeore]

I did some measuring today. My 1958, machine combustion chambers are 4.125, at their widest point and my 8554PT gaskets, measure 4.570 to the corners of the gasket, 4.330 at the closest point, between cylinders and 4.325 vertically. That's a average of 4.408 so, I will call it 4.400 x .051, and will call the volume at 12.71cc. I think that will be pretty accurate, at least, until a official volume can be cited.

I think the Mahle/Clevite 3389, might be a better low cost choice than the 8554's for many.

[blykins]

I did some measuring today. My 1958, machine combustion chambers are 4.125, at their widest point and my 8554PT gaskets, measure 4.570 to the corners of the gasket, 4.330 at the closest point, between cylinders and 4.325 vertically. That's a average of 4.408 so, I will call it 4.400 x .051, and will call the volume at 12.71cc. I think that will be pretty accurate, at least, until a official volume can be cited.

I think the Mahle/Clevite 3389, might be a better low cost choice than the 8554's for many.

I wouldn't put too much effort into trying to figure out the diameter.  The difference between a .051" 4.320" gasket and a .051" 4.570" gasket is only .12 points or .089cc. 

[CaptCobrajet]

You should add the Fel Pro 8045 PT and the 9061 PT.  Heavy duty truck gaskets.  They will compress to .051 and .061, respectively.  Not quite round, but mostly a 4.200 bore.  Very good gaskets.

[frnkeore]

Thank you, Blair. I'll check them out.

[blykins]

I think the 9061’s are in the process of being discontinued.

[frnkeore]

They seem to be the perfect head gasket for my build and give me just what I want compression wise. Because they are not round, I used 4.25 to calculate their capacity.

I ordered a set today.

Thank you, Blair.

 

[My427stang]

Frank, are your pistons sitting proud?  If I understand the thread, you chose the .061 head gasket, wondering the reason.