Yikes I have never seen that ever
deffinetly melted through the cooling passages.
You say the heads were ported were they decked also.?
wondering if the port job got into the cooling passages by the valve stems
I would say lack of water and the heads were not Torq down properly on the reinstall...
I don't like the way the sealing ring surface
is so small in that area .?
usually they will warped between cylinder
and not to be "That guy"
but this is way I try to use good quality (new)
Headbolt when I putting new headgasket on

....wOW. ...thanks for the pictures
those heads are "Toast"

 

They were decked at least twice...maybe three times tops. You can also see where the hole extends through the outer wall of the head casting too.

 

 

Are you referring to this?


I looked at the piston tops, and I see no pitting or irregularities at all. They look perfect to me. I want to believe that the tune is ideal because the guy who did it, really has a terrific reputation around these parts. He spent a good deal of time on it and knows this stuff well. Looked at the cylinder walls again, looks great and the motor turns smoothly.

So upon rebuild, I want to make it more detonation proof than before. IIRC, the gaskets that were used were the .030 gasket (forgot brand). But on the next build, maybe I need the thicker ones for reliability. Not looking to squeeze a few HP at the expense of reliability anymore since this is ONLY a street car.

 

 

Thanks again. Heads are going to the shop tomorrow for analysis. I am coming more to the conclusion that I had insufficient coolant in the motor, and it just fuggin burned up.

 

Yep... heads are destroyed! The 355 Forged shortblock will go to the shop for a look this week for a look, but I expect to be reusing. I have no interest in stroking it. I just dont want the added expense and baggage to go that route.

So since I am getting the pleasure of going through this **** all over again, I am looking to AI to port the heads this time, and spec a cam. I have already sent them a lengthy email explaining goals and requirements. The biggest requirement this time...RELIABILITY! I absolutely want a combo that is first and foremost reliable...even if it means given up a tad few HP. This is simply my fund driving street car and will likely never see the strip again. But Ive got to have some piece of mind knowing the the components are going to work like they should.

So I am looking at the 190 AI heads and a 226/230 or 226/234 cam to start with.. which seems very similarly spec'd to what I had before. Would you guys recommend this...or something else? I have really been out of this scene for a very long time but it appears that AI is till the way to go in LT1 land. What do you guys think?

 

I think that was close to the same setup that speed_demon dolt was running after the valve guides in his LE heads cracked. IIRC he was in the mid or high 11's at 120mph with the wrong gearing (I believe he was running 3.73's which made 6th gear useless). Stock short block.
Do you have any idea where those chips off the combustion chamber ended up?

 

No idea unless they are down in the pan or in the coolant passages. Or maybe they were pulverized by the piston, there is quite a bit of metal flake around.
You mentioned the block being decked. It was just barely decked a single time and thats all. Its not near zero decked at all. Not sure how much, but the piston is certainly lower than the block deck surface.

 

Find out - magnetic base dial indicator, machinist's straightedge and a feeler gauge will give you the answer. Rotate the engine for each cylinder with the dial indicator where it won't bottom out with the piston at TDC. as the piston comes up, watch the dial to see where it stops and then the reading goes back down. That spot where it stops is where you measure. stop rotating there and lay the straightedge across the bore and use the feeler gauge between it and the (center) top of the piston. You'll probably find a little variance between cylinders, maybe as much as .003-.007. i.e. a range from .012 to .017 on a ".015 decked" block. The better machinists can get the variance < .002 across all 8. Your preferred math (mean, median, mode, average) to pick the deck height number you choose for your SCR/DCR/quench calculations & head gasket choice. Knowledge is (horse) power.

 

Thanks Gojira,
Engine builder will be looking it all over soon.

Another question for you guys. Are the ARP heads bolts that were used, now possibly damaged from this severe overheating? When I just recently removed them, the vast majority of them were not very tight at all. Could this mean that the bolts stretched?

 

... or they were loose to begin with which may have been the cause of your initial problems. I'd just replace them.

 

Doubtful they were that loose and survived 7 years. But yeah, might be best to replace them at this point.

It is funny how the head can be so .020" warped upwards in the middle, and the bolts be that loose during diassembly. I would say they were less than 30# of torque. Not sure of how the physics of that, really work. But maybe the bolts did stretch after-all.

 

Or you distorted the threads in the block etc.

IMO I would replace the bolts and double check threads in block. Aluminum will distort much more than steel at the same temps so its very likely you just slowly loosened the bolts with heat cycling to the extremes you say.

 

Motor is torn down.

As expected...carnage.

Some pistons turned black in color, due to heat. Might be best to just replace them.
Rods seem okay.
Cam is destroyed.
Crank appears okay.

So a acquired a non-molested 4 bolt long block. So that will be the new block, heads and crank. Heads are the desired heads for porting. So at this point, I am simply looking to stay with a forged 355 and the 226/232 cam.

So here we go again.

 

Is AI about ready to do another run of LT1 heads? It may be good timing for me to go ahead and get a set done I've had waiting for years.

 

Who ported those heads? Whats up with that quench radius?

 

**** on AI. They never once responded back to the several emails I sent them. Crickets...Nothing! Would have been willing to wait for the next run.
Sending them to LE instead.

Getting ready to build the new motor. But this time, I have a 4-bolt main block to start with. Pretty much putting the rest back together, the way it was before the meltdown.