My 72 Comet Build.....

I have no doubt that it will be a wicked ride on the strip

 

Took it to the track Wed nite and this is what it looks like under the hood today.....




Aparrently, my head gaskets didn't appreciate 22.7 lbs of boost.....

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I thought it was because my 862 heads are the early notched deck ones..... But as it turns out it appears that it pushed the gasket out on the hole next to it first..... There are no signs of any detonation, I think it was probably just that the GM 12558940 composite gasket just couldn't hold the 22.7 lbs it was making..... It blew the driver side, I believe 5 first and distorted the gasket so much 3 went too..... The pass side was not blown, but it looks like the gasket was moving around a little from the scuff marks on the sealing ring.....

The shortblock looks fine.....No water in the oil at all..... I will get the deck surfaces cleaned up and ready to go..... Time to do a little research and figure out if I need to replace the heads and what gaskets I should use either way.....

Here's what it looked like when I pulled the head.....






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Arrrgh, guess you found out what the weak link was now

 

Sorry to hear about the problem Frank . What's the next step .. are you planning on cranking it DOWN a bit ..and then try it again .. Hope everything works out for your.

Cometized
(Chip)

 

It happens..... I have not made a final decision yet, I am still researching some things and need to make a couple calls.....

 

I finished taking a couple things apart this morning, then cleaned the deck surfaces on the block and heads..... After that I took most of the parts to work and washed everything, plus I have a nice steel block at work I have used to block and check deck surfaces..... I did a fairly quick going over the heads with some 320 and the surfaces look really good..... Then I took everything back to my shop and did a really quick blocking on the block deck surfaces and they look fine too.....

I have done some research and have a couple options, I need to make a couple calls tomorrow and dig a little deeper.....

Here is the driver side head(side that popped) and the pass side head after clean up.....





Here is the block after quick scuff, driver side then pass side.....




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Nice! The head looked bad from the pictures but not seeing it in person it was hard to tell if any metal moved. Looks like they cleaned up great.

 

Yeah. nothing was that bad..... Probably because it wasn't lean or detonating..... Just pushed a gasket out from under the head.....

 

Here's a little update.....

The block and everything in the car is all cleaned up and ready for reassembly..... I put some new comp short travel lifters in it, I wanted to try something different then stock because I was getting some lifter noise..... Also the lifters seemed to be collapsing when I lift after making a pass.....

First I thought I would try is a different head gasket, so I ordered a set of MLS from the WS6 store that are for the notched heads..... I also have a set of Fel-Pro Permatorque MLS gaskets for this application, the new ones looked like a copy of the Fel-Pro's..... I was told by Fel-Pro the didn't recommend using there's with boost, so I didn't feel comfortable using either of these sets.....

Next I decided I would get another set of 862's I have freshened up and just use them since they didn't have the notch..... Well the seats in them were shit, which makes that endeavor not worth wile..... I was talking to the machine shop guy we use at work and he said he had a set of LS head off a motor the ran good, just smoked..... He said I could have them if I wanted, turns out they are 799's so I said great..... He's doing a valve job and surfacing them, so I'll have $300 in the fresh and ready to go..... I'll probably do a quick port and pocket clean up on them when I get them..... They should be done Monday.....

I also bought a set of GM LS1 MLS gaskets and a set of the infamous LS9 7 layer MLS gaskets..... I am leaning towards the LS9's even though the bore is a little big.....

Since I was waiting anyways I went ahead and pulled the trans pan and checked the filter, everything there looked good so in went a new filter and put it back together..... I thought it would be a good idea to check since I have quite a few passes on it since I broke the stock planetary set.....​

 

Picked up the heads today.....

 

OK, I have been a little lazy both working on it and updating..... Last Saturday I cleaned up the bowl area on the 799's I got..... I didn't see any reason to do anything to the ports themselves.....

A little before and after of the bowl areas.....






Then Sunday morning when I was getting ready to assemble the heads, some dumbass knocked on over on the bench on the face and it fell right on an 8-32 stud from one of my cross buff arbors(by the way I'm the dumbass)…..

Here's the mark it leaft…..



So I took them back to the machine shop this week to get them surfaced again.....
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I managed to assemble and clean them up this morning without incident….. I cleaned all surfaces on the heads and block..... Install the head alignment dowels and took the LS9 gaskets out of the package and set them in place dry, then set the heads in place..... I was going to install the arp head studs but my arp lube was hard as a rock in the container, so I leaft it like that and went by work so I could pick up some arp bolt lube for tomorrow.....

Here's the gasket the heads in place.....



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Got a little more done this morning..... The heads are torqued on, and the grounds all hooked up on the back of the heads(so I don't forget them later)….. I also checked the push rod length on all 4 outer corners.....

 

Nothing got done on the Comet this weekend, just didn't feel like working on anything..... I haven't been overly thrilled with the new Mustang, so I went yesterday and traded it in on a new F150 SuperCab XLT/Sport..... I already like it much more then the car.....