blown 2 head gaskets

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LETSRACE

LETSRACE

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So far this season I blew two head gaskets in the same spot.The top of #2 cylinder, it blows into the motor and blows oil out every seal and hole in the motor. I have a 340 with the high comp. pistons, .030 over bore, Standard stroke, 360 j heads, six pack carbs and manifold, shooting 150 h.p. NOS, MSD set at 6500 max and removes 4 degrees during NOS spray. I have an rpm switch to turn off NOS at 6300 to keep from spraying on the limiter. I also have a WOT and fuel pressure switch to stop spray if not correct. Running about 6 psi fuel and 900 psi NOS. I use VP fuels 105 octane. The block is o-ringed to keep from blowing the gaskets??? I have ARP head studs not bolts.I looked into copper gaskets but not sure if that would help or cause a leak issue. I had the head shaved and the block checked, no problems found. The o-rings stand up .010 above the block. I am using FELPRO 8553 gaskets. No overheating, it happened on the first run of the day the last time.I am getting real good at changing head gaskets and would like to move on from this problem, any ideas would help.
Thanks Frank
 

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i have a couple ideas... usually blown head gaskets happen from detonation. but i have seen one thing that dosent happen often.on a set of heads and a block that were decked to the extreme and the dowel pin were too long causing the head to not seat all the way.
 
The 8553 is a stock-ish gasket, try the 1008, or Cometic MLS. Sure the Cometics are more, but you can reuse them. 1008 will give you more comperssion as they are .039 compressed as opposed to .045 for the 8553. Check the archives, a guy ran both and stuck with the 1008's. Even talk of Detroit Performance line Gaskets being better than FelPro.
 
8553 is used as a general replacement gasket. You need to step up to better gaskets.
 
Um... If the block is O-ringed, you have to run the O-ring type head gaskets. You are not doing anything IMO that requires the O-rings if the head and block were machined properly, and you're using at minimum ARP head bolts if not studs. But, you can't run the standard head gaskets with the block O-ringed and expect them to work. If you need to stick with the .045" thick deals use these:

http://www.summitracing.com/parts/SCE-T69064/

Again, your block and heads must be flat. VERY flat.
 
I have a pair that look like that, the grey MP performance composits. 3 cylinders on one bank, one on the other.

My guess is head lift/dowel pins holding up head; intake pulling up head. What do you use to seal the ends of the intake? Is it bottomed out on the china walls(end rails).

If you swap the heads side to side, does the problem move with the chamber? Have the heads been ported? Look for a water leak.

Another thought: I don't think it's detonation, if it was, detonation that violent would crater or collapse the crown of the piston and/or ring lands, and it wouldn't be limited to 2 chambers.

My money is still on head lift.

Check it out and let us know.
 
i know where you re at I ve been there

few thing can do things like said earlier
-to long of dowel pine
-heads and block arent straight as it was suppose to
no more than .002 of distortion on each side (block and heads)
-detonation are you sure the timing is set correctly maybe the damper
rotate and the timing are is higher than what you aspect
or not enough fuel

-now the heads gasket,what you are using arent the best by far
the 1008 is far better and can be use with oring not the best option
but can be use
the copper gasket like moper mention are better but I used them and pretty hard to seal because no sealant are on them and you need to use silicone around every water and oil galery not enough it will leaks and to much will plug the galery and gave you problem letter on
but you can use those every thing is there no need to use silicone

http://www.summitracing.com/parts/SCE-S69154/

-after that you can use the mls style gasket but you gonna need to remove the oring redeck de block to remove the oring groove because all the company that are selling this kind of gasket yanna have the heads and the block as straight as it can be I talk to mls gasket and told me it was the only way to use there gasket

thats what I did
 
Thanks for all the replies, I knew I could get some great info from this site. I checked the dowel pins 1/4 inch extra depth in the head. I will check the TDC on #1 to confirm the damper did not move. The shop that built the motor thinks its not enough fuel in the front of the motor during the launch. They think it looks like the gaskets got hot and blew out. I'm thinking about trying a second fuel pump and regulator for the NOS at a higher pressure and maybe a larger fuel pill on the front NOS plate. I am now running the one Holly "blue" pump for everything, total H.P. between 550 and 575. The motor shop said the gasket may be the weak link and if I get a gasket to not blow it may take something else out harder and more money to fix.

Any thoughts on the low fuel and weak link theory?
 
can be fuel starvation
but both time a the same place??? hummmmmmmmmmmmm

of course the heads gasket are the fuse in your situation
its the cheapest links in your engine

for fuel delivery for sure the blue pump arent the best choice
but I ran about the same set up as yours with the same pump
and I change mine for the black one but no need
to go biger and bigger pump if the line are too small
or the fuel pick up in the tank still the OE 5/16

you can buy the 1/2 from mancini or else where its pretty cheap
I made fuel line with russel 5/8 hose I install 2 fuel regulator
one set 8 psi for the carbs and the other at 5 psi for the nitrous
why 5 more than that my nitrous systeme were to fat
but Im using a nitrous work kit and they are that way as said
by there tech when I called them to answer to all my question
 
When you have the wire in the heads or block, you need to use a copper gasket, and the gap in the wire (where the wire's ends butt) should be positioned nearest a head bolt hole. I agree with others who say you don't need the wire anyway, but you have to have the correct finish for the gasket you use, and it looks to me like the front fire rings failed, but there's gas escaping from every hole. MLS needs a very smooth finish. If your engine was not built with them in mind, I wouldn't bother trying them. Use a daed soft copper gasket witht he wire, and you should be able to withstand the power. What do the piston tops look like? How about the spark plug ceramic? If you see any signs of detonation you HAVE to addres it. The blue pump "should" be more than enough, but whenever possible I have a dedicated NO2 fuel system.
 
Fuel starvation equals lean, lean like that says scorched piston; is it?
 
The pistons look good, the spark plugs are Autolite #403 and are like new. the only difference is the exhaust valves on the front cylinders have a lighter color on them like their running leaner than the rear.
 

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I don't want to belittle or bash anyone.........BUTTT

Come on you can't run a 1008 if the O-ring in the block diameter is not larger than the one in the gaskets. If you plan an O-ring job and do it with the intention of using the 1008 that is fine. But, 99 times out of 100 that wire aint in the right place. A properly done O-ring job will not have gaps. A good installer will put them in where the best eyes can't find the ends.

Surely you do not expect a stock replacement gasket to hold the compression you are running along with 150HP nitrous. It just don't work. There might be a rare case but, come on.

Call Clark or SCE and order some copper gaskets. Get some copper coat from the parts store. Clean the gaskets with a paint grade solvent. Hang em up. Spray a light tack coat. Then spray another coat of the copper on them. Figure out how they go on the engine then carfully lay them on the block and start putting that puppy together. Get the heads bolted and torqued down as soon as possible. With copper and O-rings done properly you can push the mains out of the block before that gasket will fail.

Leon
 
It looks like the block side simply wasnt sealing at all. Not the gasses anyway.
 
are you sure the block is straight
and the heads

the shop who did it was he using a stone or a cutter(knife)
on is machine

the first the guy did mine he use a stone
and the seem to be straight but hade more than .003
where the cylinder are there is less metal so the stone
wasnt doing is job correctly and was (grinding more metal)

for the valve color could be the prestone or water the engine burn

buy a copper or multi layer gasket retorque does heads
and go racing
 
Here's some food for thought: Here's a pic of my pair of blown head gaskets. They blew during a run down my local 1/8 mile track (went 8.2 sec), first and only run; brand new engine: 360, .030 over KB-107 pistons, ported "J" heads, M1 intake, 12+ compression ratio. Had to push the car up on the trailer, didn't run any more:cry:.

This happened in 2006. I spent more than 2 years trying to figure out what happened. I asked dozens of people if they had a clue, mailed the gaskets out to be looked over by a learned professional. Many said "i don't know", lot's said "detonation", a couple said ".. head bolts bottoming out in the block", two suggested "possible head lift". I let all of this rattle around in my head, checked bolt engagement in the block five times; during build .020 was talken off block, .035 taken off heads. With the heads off saw no signs of detonation, I could still read what I wrote on the crowns during moch up, figured that detonation that violent would have shattered a piston; hypers are strong, but they are brittle. Looking at the block after the intake was off, the film of RTV I used (high temp red) to seal the ends of the intake was transparent to the block and thinner than a piece of paper. I asked more people about head lift, they didn't think that an aluminum manifold with 6 3/8 inch bolts could pull against an iron head held down with 10 1/2 inch bolts. After a while I remembered something I read decades ago in "Ripplies Believe it or not".......a fly landing on a 1 inch dia solid steel bar will cause a measurable deflection. Is the deflection significant...........no! It is, measurable! I only remembered it because it seems so improbable. Score a point for head lift!

There was another factor in all of this, the chambers that blew also were slightly lighter color than the others. After I cleaned up the engine from all the gasket debris, I put new gaskets in; Cometics; screwed it together and fired it up........steam and water pouring out of the headers, blaim the gaskets, install another set; Mr Gasket, Ultra seal, never fired it had water coming out of #4 spark plug hole, tear the heads off, took them to a shop for inspection, passed a magniflux, close visual inspection with a jewlers loop found a spot in the intake bowl, the guy took a scribe an pushed it thru the wall of the bowl like he was going thru tissue paper saying " I think I found your problem.........."

After all of this I concluded: clamp on the head gasket was reduced by the intake bottoming out on the end rails of the block, water entered the cylinders, during combustion the water turned to steam, created caused a rapid sharp pressure spike, blew the gaskets out.

Just some thing to think about.

Good luck
 

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UPDATE: I switched to SCE copper gaskets, cleaned all services with brake cleaner, used a thin film of black RTV around all port holes. I put a new o-ring wire in the problem cyl. The problem head was shaved in the mill, (NO STONES). I also crossed the heads so the old #2 cyl is now on #7 cyl. Ran on the street a few times and all seems good, I will post after next time at the track Sept. 10th. Thanks for all the time and advice.
 
i run flat out gaskits and have never run into any problems have had felpro faile once but that was it .
 
Update:

Over one month with copper gaskets and two trips to the track, 7 nitrous runs, no leaks or blown gaskets. Its nice to return from the track and not have a problem. Now on to getting a better 60' time. Thanks for all the help.
 
Lots of knowledge to refer to on this site. Usually someone out there can help with your problem. Way to go guys.
 
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