blown headgasket?

[Chache876]

pics are here: http://pg.photos.yahoo.com/ph/chache876/album?.dir=bb29


this is off my 360 with about 150 miles on it...


also i noticed on the cylinders there is a ring around the top, is that normal?

[64dartwagon]

kinda looks like the mating surface had somthing on it and caused a weak spot. Or the gasket got nicked or shifted when the heads were dropped on. But that is from only what I could see on this monitor of mine. I would straight edge the block surface and cylinder head to check for straightness, no warping.

[Chache876]

how do i straight edge it? what do i look for?

[Stoga]

Originally Posted by Chache876

how do i straight edge it? what do i look for?

You'll need a straight edge tool, made specially for this purpose. Handle it carefully because it is a precision tool. After you are sure the surface that you are checking is perfectly clean, lay the straight edge from corner to corner, then across, checking with a feelers gauge if there are any gaps. Anything over .005 inchs iis a definate concern. Check both the deck and the head surface. If either is warped excessively, you'll have to have it machined flat. Naturally if the deck surface is the one that is warped, you'll have to disassemble the engine.
Luckily, due to the thicker metal, decks dont warp near as easily as head surfaces, and thicker head gaskets can be found to help take up some space, though you lose some compression ratio when using these.
Looking at your pictures, unless you were using NOS or some other combustion booster, I half suspect your heads werent clamping tightly. When the engine was rebuilt, did anyone take an run a tap thru the head bolt holes? If you have any kind of trash or junk in the bolt hole threads or piled up in the bottom of the bolt hole, the bolt wont clamp.
Also, while this isnt that common on Mopars, check your head bolts to make sure you dont have one stretched. Measure them against one another and look for any large differences.
That ring around the top is just where the cylinder isnt cleaned because it's above the piston rings, it's only leftovers from combustion, nothing to worry about.

[littlecampbell]

That sucks....so how do you like the shorties?.....even if only 150 miles?

[Chache876]

i dented them right after i put them on backing out of my garage.

[littlecampbell]

You mean the pipes???....did you route over or under the center link? Reason i ask is not too many testimomys for the hedman shorties on an A body...which i presume yours is? I have yet to have a problem with mine...Any info on your installtion would be fine....

[Chache876]

theyre actually full length dynomaxs. they hang real low on my demon. the install sucked. took less time to put the motor and trans in then just one side

[littlecampbell]

Okay.....they looked kinda like shorties....sorry to hear about your H gasket. Happy New Year....

[Billydelrio]

Things to check in addition to surface flatness:
head bolts bottoming in hole
dirty or damaged threads
head bolt holes counter sunk one thread
aligment dowel height

What pistons are those?

[heigleracing]

use a spray on adhesive like a copper tac. You spray on both sides of the gasket then put on the block. it does help seal things up. the pics look like the gasket just gave up. It didn't look as if the motor leaned out or anything.

tips on head gaskets. Use the fel pro 1008. its the best we are going to do for our sb motors.

When torquing the head, make sure you use the torquing sequence and increase the ft lbs in 10 lb increments. After you are sure that things are tight and up to standards, let the motor sit over night and re-torque again.

If you do this, then you know your doing everything you can to make things successful.

make sure the block and head surface are CLEAN AND DRY before fixin.

Good Luck

[Chache876]

thanks for the tips, it was a fel pro 1008 gasket though haha.

[Chache876]

well i just finally got the other head off (damn headers) and that gasket was crap too. not as bad as the one in the pictures but definatley garbage. oil covered, torn etc...Only on the front two cylinders on that side as well. Pistons looked a lot better but i saw that my fogging oil had let me down, looked like some surface rust was forming. So i hosed that down with more fogging oil. Anyways until i know better i am blaming it on the heads not being straight (<--praying). I have a spare set that needs some cleaning up that i will put on for the spring.

[racintracy]

I don't know about the machine shops in your area but the 2 we have around here are real good about laying a straight edge on a head and checking it for free usually. If not it shouldn't cost much. i.e. $5-10??

BTW: You weren't running nitrous were you?

[Chache876]

nope no nitrous, barely went over 65mph. im just hoping its the heads and not the block. with my luck it will be the block haha.

[robboski]

when using a composition head gasket, as yours are, DO NOT USE a sealing compound. the composition gaskets have sealers embedded in the gasket and many times additional compounds will cause a chem reaction which can burn the gasket. in the picks the fire ring was what was blown. this indicates either imroper torque/sequence,or a problem with the gasket surface whether it is warpage in the head or block or both or simply trash on the surface, also could be "gasket cut" in either one. in your picks the piston appear to be at least similar to the 10.5:1's used in some of the M P crate engines. You may also want to look at the torque requirments of the gasket itself rather than the factory recomended. some of the victor/felpro gaskets for the earlier engines require 90 lbs rather than the original 70-75 lbs

[webslinger60]

Originally Posted by littlecampbell

did you route over or under the center link? Reason i ask is not too many testimomys for the hedman shorties on an A body... I have yet to have a problem with mine...Any info on your installtion would be fine:

Just a side note off the topic. I am planning on putting Hedman 78500's on
a 318 in a F/M body (similar underhood dimensions as an A). Hedman originally designed these for trucks, where the steering link is lower and there is enough room for a smooth 90 degree elbow. On cars, it's real close.
There were some pics over at the MS forum of a 360 Volare with them. The guy had to go under the steering link on the left side and went over on the right, but had a very tight 90degree corner pipe welded to the collector which kind of "pinches" the flow. And the pipes then angle outward almost to the frame rails to clear the "swing" of the idler arms. Going under & close to the road, and all that piping kind of negates the idea of "shorties". A member told me about these "angled" reducers from Sanderson
( www.sandersonheaders.com/reducers.htm )
Im going to try these, with 45degree elbows. I hoping this should clear everything without tight bends. The only other alternative are "Spitfires".
Laysons restorations ( www.laysons.com ) bought the design and they are making them now, but charge $450, and you still have to weld the collector on yourself.