Head gasket question

[78cordoba]

The engine is finished getting machined and crank polished. I will be working on getting it put back together now but could use some help along the way. It was bored .030 over and has kieth black 240 pistons, I'm at a loss of what head gaskets to get. Could someone shed some light on it. 78 Chrysler 6.6 400

 

[Kern Dog]

In almost every instance, I have used Fel Pro Perma Blue whether it was with iron heads or aluminum.

 

[78cordoba]

In almost every instance, I have used Fel Pro Perma Blue whether it was with iron heads or aluminum.

how about size due to the fact it's bored .030 over now will a standard one work or will it have to much overhang

 

[Kern Dog]

.030 is a tiny fraction of an inch. The Summit Racing site lists the specifications of the Fel Pro gaskets. I think the #8009 is the one you need but I'm not certain. Their site filters will lead you the right way.

 

[beanhead]

how about size due to the fact it's bored .030 over now will a standard one work or will it have to much overhang

Felpro 8519 has a 4.500" bore size...should be plenty.

 

[69 Sleeper Bee]

No. There is no overhang.
The head gaskets are made to take more than can be max bored.
Compressed thickness is the big difference in what compression you want to achieve.

 

[diesel_lv]

Felpro again. I'm a fan of MLS gaskets, but the heads n the deck have to be prepped for them. I've got Felpro on my 600+ hp 496. No problems.

 

[BSB67]

Felpro 8519 has a 4.500" bore size...should be plenty.

This right here. And not because of the large bore, but because it is a fine gasket for your application and you can get a pair for $40.

 

[66Satellite47]

Fel Pro, I've used the 8519 in the past, but I prefer the 1009, it's designed for a higher compression motor and uses a different surface material that may allow re-use.

 

[snakeoil24]

Save yourself a great deal of concern call Cometic the best head gasket in the business!

 

[78cordoba]

Ok thanks all. Yeah the deck has not been machined, just the cylinder walls. This is kinda a budget build. I just want to get it on the road for cruising at this point I will probably go with felpro 8519 then.

 

[66Satellite47]

Save yourself a great deal of concern call Cometic the best head gasket in the business!

Only issue with Cometic, is the need for the specific block & head machining surface.

 

[furious70]

You can't just use a cometic without your machine shop knowing and finishing correctly.

You also don't need to buy a special 4.5" bore compatible gasket. You don't want overhang but there's also no reason to have the gasket pulled back from the cylinder

 

[66Satellite47]

Not sure how they figure a FelPro 8519 is a 4.50 gasket. They are sure good at 4.375- 4.380. Will easily take 4.38 and plenty of chamber clearance for a head chamber ported out to the stock head dimension to match. The 8519 just doesn't have the same sealing ring as the 1009.

 

[beanhead]

Something to keep in mind...the gasket bores aren't perfectly round. So you have a cylinder at 4.370", that's only .065" clear per side at the widest points on the gasket before you take into consideration the cylinder chamfer (sometimes pretty generous on 70s blocks)...no reason to cut it close IMO.

 

[78cordoba]

I need to correct myself i must've measured wrong initially. got the motor back from the machine shop it is bored .040 over to fit the set of pistons I have

 

[66Satellite47]

The FelPro 8519 is plenty good for that. On my high CR (12.2 ish) iron head motors they would show possible leakage on the center cylinders after a couple hundred runs. With a lower CR motor and a cruiser, should be perfect.
The OEM steel shims don't seem to readily available any more.