You can beleive what you want to beleive. I have seen plenty of boost cars Frag #5 and #7

#6 is an odd ball but either it is the tune or pushing too much boost. The gasket lifted in the weakest point of the set.

As for the shop, Id like to know how they were running the fuel rails
GM didn't designate 1 particualr piston to go into the rear of the block.

If the fuel rails face the same way, then when you get the back of the block, there is less volume/pressure hence that cyl takes the hit.

 

Dang Chad, you have had some issues with your car. I hope you go iron and stop playing with the Aluminum blocks. You have spent a lot of knocking your head against the bricks...............good luck. Yes, Brett does SD tunes as he just finished mine.

 

That's what happened when I cracked the block on my LS1. Lifted the heads from detonation and broke the #7 ringland, blew a head gasket, hydrolocked the motor, and cracked the block.

It was from lack of attention to detail and too much boost on stock internals.

Truth.

What MAF meter are you using that is of any use at 16psi?

More truth.

 

Thanks for all the input guys.

Cliff- yea, im done with aluminum. Wish I could afford an LSX, but an iron 370 is in the works. I am planning on pulling the engine out this weekend and then taking my crank and rods and main studs down to Xtreme Horsepower in fort worth next weekend and have them build me a 370 with either diamond or wiseco pistons. gonna bump compression down a bit too to 9.0 or 9.2 depending on which piston I get.

 

There are a couple people that do SD tunes down here in OKC. I would have had Brett tune my car, but he is running a one man show and he was backed up. Jim at SWtuning did my car, and did a good job. Hptuners is really nice to have...

Not sure how he talked you into a MAF tune. SD seems to make the most sense, and there is a reason why most the people on this forum use it.

 

Well, my tuner doesnt really do SD tuning last i checked, so I was just using the MAF.. I know SD is a better way for FI. I did plan to eventually get an SD tune, but I guess now is the time to do it..

 

aluminum block is fine for what you're doing, I woudlnt' add the weight. Your problem is in the tune/assembly.

 

I would have to agree with Tiago. Sounds like it was detonating prety bad, and the block was the first to go. After you get your new setup done, whatever block you may be using, have the tune looked over very carefully.

 

What exactly would be wrong with the assembly to cause that? All I did was put the heads on. SDPC assembled the shortblock and everything was all new. Theres really not much you can mess up putting the heads on. I torqued all the studs in the correct order progressively going tighter each time. I broke the sequence down into 4 steps so I wasnt torquing them all down to the max spec all at once. They are ARP studs with 12 point nuts and a recently calibrated snap on torque wrench was used. I torqued them to the stock specified rating. Should I have gone higher or lower or anything?

 

I wouldn't beat my head over it too much Chad. The block was leaking from the get-go so that is probably what caused it combined with detonation...we live and learn bro! Iron block, a few hundred to o-ring block and heads, SD tune that bish, log runs, and hammer away at it.

 

I meant either or. from what you're saying assembly was probably ok. Too much timing, not enough octane and too lean, or some mixture of all the above is what it comes down to.

 

yea, i guess so. I wouldnt think 17° would be too much with 91 and meth with AFR below 11.0, but maybe it happened a while ago on the dyno when my fuel pumps went out and ive just been running it like that for a while and didnt notice it till I blew up the manifold and took the heads off to inspect everything..

 

Damn Chad, this sucks man. But if you are goin 370 now your gonna be making even more power as a bright side, LOL.

 

Got the engine pulled last night. Here is a closeup shot of the crack that I couldnt get while the engine was in the car:

 

Dang Chad that's more then a crack, that's a river. No wonder you had leaking problems! If you stick a screw driver in the water jacket and pry on it, I wonder how much more the crack would open up? The crack is going the wrong way for fluid to get inside the combustion chamber.

 

haha yea i know. I'm gonna see if it breaks (or at least how far it spreads) once I get the rotating assembly out...

 

IMO its just a bad casting on the block, happens.

The intake is unrelated, the back where the plug is is the weakest part and thats where they let go. All it takes is a small crack or leak under pressure and it pops like a balloon.

 

yea I thought the crack was in the cylinder sleeve, that is a block problem..