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Lifted Head killed composite

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DSM Chase

10+ Year Contributor
778
51
Sep 19, 2011
Senoia, Georgia
Was doing some e85 34psi pulls on my stroker and the head lifted and killed the gasket, this was on standard ARP stud's at 90ftlbs with a Mitsubishi composite gasket, coolant all in cyl 4...

Now I know people highly believe in l19s but was this really the standard ARP stud's fault? I find it hard to believe the studs are to blame.

BUT my main question and I know this is highly controversial and everyone has their own opinion about it so I would like to just gather everyone's thoughts. I have at the house now both a Mitsubishi MLS and a Felpro perma MLS, the block was resurfaced a few months back and the head looks to have never been surfaced... Thinking I can get away with them not both being surfaced but skeptical... Thoughts?
 
Blocks gonna be fine. You didn't mention the engine getting hot or anything, but you just said the head never been resurfaced? Would you seriously risk it running that boost, and a MLS on a non surfaced head?
 
Post pics of the block deck and the head surface.

Also where the head stud washer sits in the head
 
Bogus the head stud washers sat flat on the surface, some had to be modified to clear the springs.
On second thought I believe the head was also surfaced at one time but its no where close to a mirror finish.
 
Bogus the head stud washers sat flat on the surface, some had to be modified to clear the springs.
On second thought I believe the head was also surfaced at one time but its no where close to a mirror finish.

For future references, put the washers in first, then the studs. Saves harm to threads, load distribution, and potential bending of the washer, all of which alter clamping force.
 
What I am asking about or looking for is where the washer sit is flat and smooth, The aluminum can crush or deform from the head being torqued several times, and the washer has pushed in to the casting.
 
What I am asking about or looking for is where the washer sit is flat and smooth, The aluminum can crush or deform from the head being torqued several times, and the washer has pushed in to the casting.
Figured yea, I'll take a look here in a little while...gonna push my luck with copper sprayed permatorque.
 
If they are crushed out, the bolt holes need to be spot faced before you go to install the head. If not clamp force is compromised and you will be pulling it off in short order again.
 
What is the setup? 6 bolt, 7 bolt, what turbo, how much timing, any knock?

The composite gaskets can take some decent cylinder pressure, but not the knock spikes at high power. Also, the 7 bolt arps are much more likely to stretch than the 6 bolt.

I would resurface the block and head if you want to run an mls.
 
I would surface the head, I see the steel core imprint from the composite all over the gasket surface, along with a fire ring imprint down on #4 on the intake side.
 
Got it all back together and running, I cleaned the surfaces A LOT and used the mitsu MLS with copper spray, Came in for the night but the car seems to idle weak and doesnt cam Lope like it was doing before, sounds like a cylinder is down or something im going to check it out tomorrow and change the plugs...
 
Did you change the plugs after the coolant contaminated cylinder #4?

Cylinder #1 also looks like coolant was getting into it. Notice how 2-3 valves are white? Well Look at 1-4 and they are not, This is a sign of water/coolant entering chamber, They are "steam clean''
 
Torqued the head while cold to 100 ftlbs and went on a nice drive the car cruises and idles great, just feels down on power...I did put the car back in time with my exhaust adjustable cam gear still retarded 4° however I don't think that's an issue.
 
No comp test yet however these pistons and rings are brand new and nearly bulletproof, the cams were in when head was re-installed, with cyl 1 at tdc and the head with the dowel pins at 12 o'clock and timing marks lined up at vc surface you shouldn't have any piston to valve contact, The head set on perfect and easy as usual it just feels like driving with the brakes on at wide open. I was logging like 48-50lbs a minute airflow and 480-500hp estimate, now I'm down to like half that.
 
Doesn't his valves look funny in the fact that they are all "clean" close to the fire ring? Both intake and exhaust. Most exhaust valves actually should be a whitish color if burning properly but they should be that way on the full curcumference of the valve, not just close to the sparkplug as exhaust gas exits around the entire valve or am I looking at it wrong? When you introduce water into the cylinder it should steam clean the entire valve not just half of it. Its an old time mechanics trick to actually do that with a bottle of water to get rid of carbon deposits . MTC
 
The gasket was blown in several places so there could have been coolant in all cylinders, I'm just glad it's back together hopefully it irons itself out I'm putting it back on 93 pump when I get home.
 
It does appear to ME that you had some coolant in all the cylinders because of the appearance of the valves close to the fire ring. Was the head nice and true ? Did you check it with a flat edge or anything? Just hoping it isn't warped a tad bit now and giving you some problems.
 
I'm having similar problems. Got my block and head back from machine shop. I put everything together and I blew a hg. I thought ok maybe I messed up so I re did it making sure everything was perfect and used a new gasket. Try 2 was a failure.the only thing I can think of was block wasn't resurfaced cause it didn't have that fresh cut look on the mating surface
 
Id check the head for true flatness with a straight edge. Especially since youre now on an MLS gasket.
 
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