Head Gaskets

Finally got the heads off. This is a first for me at pulling heads in suspect of failed gasket due to boost. I'm not an expert here but I think what I see is pretty conclusive. Have a look and tell me what you think. Only Cyl # 1 was holding on good. # 4 hanging by a thread but all others were pretty much goners.

Here's # 1 holding. The rest look bad to me. Please confirm.

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These heads were milled .012. The intake was not milled. Is it possible the intake was not allowing the heads to be free in expansion and contraction, thus lifting on the top side?
 
I wouldn't think so. Once you have the block clean take a known good straight edge and check it for flatness.
Just my .02 I torque my heads with arp bolts in 3 steps 45#, 65#, 85#... might seem excessive but I have never experienced a failure.
 
The gaskets which just had this failure are the 9333PT1's. Looking at the surfaces sure looks like head lift contributed since the top sides of most compression rings are blown through in a similar pattern on each of the cylinders. Can head lift really happen at 10psi? I need to understand what happened so I don't keep going through this again. I must have really screwed up the torquing of these heads or something.

After verifying surfaces are flat, I might go with Cometics and ARP studs. I'll copper coat the Cometics to help get a good seal. I'm considering ordering thicker Cometics to offset the fact my heads had previously been milled .012. Hoping this might drop the compression back closer to stock and also help with intake match.

Any thoughts on this idea?
 
What did the plugs read? AFR? what cr are you running? all these things go into it, what was your timing set too? at 10psi you need to pull at least 5* of timing, a9l with 10* base has 30* timing from 4500rpm up that's WAY to much at 10# of boost.

I don't like the cometic gaskets they never worked out on our nitrous cars.
 
I have a picture of the plugs but not handy so I'll put it up later. Looked normal. AFR 11.5ish give or take a tad. CR is actually pretty close to stock 9:1 since the gt40 (non P) heads had slightly larger cc volume than the stock e7. Although the gt40's were milled so that probably brings me back close to stock CR 9:1. 10 initial timing and chip tuned for the setup by 84Ttop & gang.

By the questions you're asking, is detonation what you're thinking? Not likely all things considered. Most likely is poor job of tq on the stock bolts.

I'm just torn between trying the 9333 again or trying Cometic. Either way I'll use arp studs. I'm sure my tq specs will be correct this time. I'm not sure they were correct last time.
 
I just went through the same thing if you can remember,I feel you pain...lol.....I ended up using the 9333s,wrather it not blow!,but I like the fusible link idea
 
Use arp studs and the 9333's IMO. The studs will keep clamping force even and you'll still have a "fusible link" with those gaskets. Also cometics require the block surface to be machined properly for proper sealing(I was told this by an engine builder and he talked me into not using my cometics)
 
I'll give the 9333's a second chance. This time I'll add ARP studs and borrow my brothers Snap On tq wrench. I had a cheap one last time. I probably didnt get em torqued right. The cold weather made me temporarily loose interest. I'll be back, I promise.
 
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Done yet? If I can manage to finish in 2 months with a wife, newborn twins, a 5 and a 12 year old then various house hold chit, you should be. Get off your arse and get it done. Its already Feb and will be warm soon... @John Dirks Jr
 
Heads are still on the bench. I didn't even scrape the gaskets off yet. I did cover the block to keep the dust out.

I know, I know...shameful... :(

I'll get it back soon