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My block is screwed isn't it....

16K views 284 replies 35 participants last post by  Jaime Lannister 
#1 ·
Many of you have been following along my previous threads discussing the issues I have been having with my built 347.

To sum up, it was burning oil from 2 cylinders. The plugs in those cylinders would foul within 30 miles.

I got to the bottom of it tonight. Ran a compression check...was perfectly fine. Did a quick leak down test by spraying air into the chamber and did not hear it in the pan. I was actually happy at this point and was hoping it was something in the head.

NOPE

Got the head off, and those cylinders have DEEP gouges running vertically the entire bore. When you feel the bore, it feels like you are reading brail. The other 6 cylinders feel great by comparison. I am already running slightly overbored at 3.905. The max you can bore an LS1 is for 3.908 pistons so I am pretty sure this block is screwed and cannot be saved but maybe you guys have a better idea.

Looks like I am smurfed. Andrew gave me a deal on that block since he is a friend at only $300. No way I will find another that cheap. I know the machine shop will try to avoid liability since it is now more than just a simple rehone and rering (they said they would cover that on their dime based on our previous discussion before we knew exactly what was wrong).

It is now a $600-800 dollar mistake....I only paid them $1800 for this job.

In b4 Mike ends up paying over 5Gs for a simple forged 347.


CURSE ME FOR NOT DRIVING THE 200 MILES TO ANDY. That would have been a minor inconvenience but it would have been done right. Yay I am now a cautionary tale. Learn from my mistake...go to only people you know and trust.
 
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#267 ·
I want to see pictures of your friend's engine bay.
 
#268 ·
http://www.ls1gto.com/forums/showthread.php?t=385778&highlight=

He's rarely on here, but here's the thread he started. I'm not sure how costly the swap was as he did everything himself. I know he converted from dry sump to wet sump but it was before i knew him so I don't know everything. LS7 clutch etc. That thread says there's 20K miles on it, I don't know if that was when I first got it or just when he dynoed it.
 
#269 ·
Over 500 miles. So far so good, just dealing with annoying issues right now.

1) Getting a chirp/squeak from the driver wheel well. I strongly suspect this is because my C6Z cat is pressed against the bell housing bolt. Either that, or it is the main belt squeaking. I ordered a gatorback.

2) The A/C belt was chirping loudly. I replaced the belt and both pulleys with advance auto stuff and it was still squeaking, albeit less than before. I am going to try a gatorback belt here as well. If that doesn't cure the issue, then perhaps it is an issue with my balancer, although it doesn't look wobbly to me. I would argue that there is more of a chance the dayco tensioners and belts just suck ass. I might try to return them.

3) I need to figure out how to insulate my interior, because now the exhaust is so quiet that all I hear is the extra valvetrain noise from being cammed. It is driving me nuts. The motor is quiet when you pop the hood, but it just gets funneled into the cabin or something. Windows up = all you hear is the valves opening and closing. Before I never noticed it because my exhaust was so loud.
 
#270 ·
Hmm only noticed in the in cabin noise after putting my ls1 style coolant tube back on. I had to bend it to clear the ls6 valley cover port and then it was pressed very hard against the intake manifold. I wonder if that is amplifying the VT noise. I am gonna go back to the ls6 one.
 
#271 ·
Ya I get alot of VT noise aswell, not much you can do about it haha.
 
#273 ·
Roller rockers will quiet the valvetrain, as will something like a 5w-40 oil.

Try insulating the fuel rail covers with dynamat first.
 
#274 ·
The odd part is, I don't really hear much when the hood is open and I am listening. I guess vettes are just weird in how the noise gets resonated.

I think if I stuffed some insulation behind the dash panel, it would quiet it down.

I just need to put a blower on so I just hear a whine. Ya that is what I am gonna tell the wife. "Hey honey, I need about $6k to fix that noise you kept complaining about when we went to dinner the other night".
 
#278 ·
At least it is supposed to warm up. Something like 60* on Wednesday.
 
#280 ·
If your head gasket was leaking at all around those two pistons , coolant could have made its way in there, and that could explain the very clean head chambers.
 
#284 ·
Pulled plugs.

All bone dry.

Woo hoooo. Also, extra ticking is coming from a slight exhaust leak I think. I got under there and the ball socket flange bolts were barely tight. I will finish up Saturday as I have to replace the manifold gaskets too.

Hopefully this weekend is the last time I have to work on it for a long time.
 
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