Cam install and a tune.

[Big A]

C'mon moneybags, you know you wanna...

http://www.chevrolet.com/performance/crate-engines/ls9.html

[abecx]

So really bad news. Engine is fucked up. I'm pretty sure it was the body shop. Sometimes in life you just have to deal with things. The cylinder walls are all scratched up, the compression is roughly 80-90 for all cylinders. Now me and the mad scientist are going to have to pull the block and replace the piston rings that they fried. You can bore the 6.1L blocks .100 over, lets hope that the scoring isnt too bad. I'm pretty much done with this car right now, mostly because I'm just tired of set backs. I'm sure in a few weeks I'll be anxious to get started and finish it. I'll have to get some new pistons or a new block depending on the damage.

Boreoscope pictures

http://abe.cx/300c/cylinder/

I am going to go pick up the car next week and probably sit on it.

I bought a LS7 motor for the 370z so at least I have that going for me. I am going to get the heads worked over and a cam for it, hope for 630whp on motor out of it. I have 2 370zs right now, trying to sell the nismo. I have the wrecked one, body drives straight so I think i'm ok there. Real excited about that one.

[Stephen]

So really bad news. Engine is fucked up. I'm pretty sure it was the body shop. Sometimes in life you just have to deal with things. The cylinder walls are all scratched up, the compression is roughly 80-90 for all cylinders. Now me and the mad scientist are going to have to pull the block and replace the piston rings that they fried. You can bore the 6.1L blocks .100 over, lets hope that the scoring isnt too bad. I'm pretty much done with this car right now, mostly because I'm just tired of set backs. I'm sure in a few weeks I'll be anxious to get started and finish it. I'll have to get some new pistons or a new block depending on the damage.

Boreoscope pictures

http://abe.cx/300c/cylinder/

I am going to go pick up the car next week and probably sit on it.

I bought a LS7 motor for the 370z so at least I have that going for me. I am going to get the heads worked over and a cam for it, hope for 630whp on motor out of it. I have 2 370zs right now, trying to sell the nismo. I have the wrecked one, body drives straight so I think i'm ok there. Real excited about that one.

That sucks Cruz, but can't wait to see both in he finished product!

[Samhain]

Looks like the cylinders were fuel washed. Did you run it much before it was tuned?

[abecx]

Looks like the cylinders were fuel washed. Did you run it much before it was tuned?

No, I was given a canned tune from the start, then we drove it around and tuned it for normal driving. The only tuning we never did was for WOT.

If the walls are fuel washed, would it be salvageable? A quick google search indicated maybe.

[akfodysvn]

why was the body shop logging any miles at all on it? I would say they should know better but based off the service they gave you on the paint job... they are obviously scumbags.

[Broncojohnny]

Did you run a leak down test on it?

[abecx]

Just a compression test. I will do that when I get the car back here.

[Broncojohnny]

Compression test is pretty meaningless except for comparison from one cylinder to the next. What are the other symptoms with it?

[abecx]

Compression test is pretty meaningless except for comparison from one cylinder to the next. What are the other symptoms with it?

The engine runs, but it will overheat if you have the a/c on and you're not moving. I have an overpowered cooling setup. Honestly thats the major issue right now that trying to solve. It idles fine and drives around fine.

We fixed the belt squealing by switching to metal pulleys.

The engine bogs like a mother fucker if you go over 3000 rpms or so. Falls on its face. Here is a video just before I took it in.

[Broncojohnny]

Well, typically if you have a problem with ring seal you are going to have some blowby and possibly some oil burning. You'll see oil on the plugs and a maybe a little smoke out the exhaust when the engine is fully warmed up. When you get into boost you might even blow the dipstick tube out of the crank case.

I did not see anything alarming in the pictures you took with the bore scope. Depending on the ring material it is not uncommon to see discoloration of the bore. If you take the heads off and you can feel the marks then you have a problem but a lot of the time there are discolored areas and they look concerning at first but they have no texture at all to them. Keep in mind that the rings are one type of steel and the cylinder wall can be iron or steel and there is chemistry in action here. Also keep in mind that the rings do not stay in one position when the engine runs, they will spin on the piston over time.

I'd definitely do the leak down test before you start tearing it apart.

[broke again]

I agree. If in fact you only have 80 psi cranking compression I am suprised the car runs at all. It should be smoking like a freight train and detonating like crazy due to oil contamination. What exactly do you think the body shop did that would cause your problems? You have other issues

[abecx]

if you have a problem with ring seal you are going to have some blowby and possibly some oil burning. You'll see oil on the plugs and a maybe a little smoke out the exhaust when the engine is fully warmed up. When you get into boost you might even blow the dipstick tube out of the crank case.

I did not see anything alarming in the pictures you took with the bore scope. Depending on the ring material it is not uncommon to see discoloration of the bore. If you take the heads off and you can feel the marks then you have a problem but a lot of the time there are discolored areas and they look concerning at first but they have no texture at all to them. Keep in mind that the rings are one type of steel and the cylinder wall can be iron or steel and there is chemistry in action here. Also keep in mind that the rings do not stay in one position when the engine runs, they will spin on the piston over time.

I'd definitely do the leak down test before you start tearing it apart.

When it was running like shit a few weeks ago, pulled the plugs they all had oil on them. At least thats what I was told, I didnt see them. You're hitting the nail on the head tho in regards to symptoms, perhaps its not as bad as it sounds.

What exactly do you think the body shop did that would cause your problems? You have other issues

I dont know, they had the car for 3 months and if you read the post, didnt return me the car in the best of condition. Those 3 months are a just a huge question mark. Its possible they only moved the car from the garage and parking along with letting it idle which caused the current issues which might not be major. Car doesnt smoke at all, idle just like in the video.

[abecx]

I drove the car home today, temps never got over 200 degrees, the AFR sat at 14.7 the entire way home. The car runs perfectly fine, to me at least. When I get a chance, the next thing I will do is a leakdown test.

There is a strong smell coming from the exhaust, almost like its running rich or an exhaust leak. It could be because I have brand new cats with maybe 200-300 miles on them, whatever it is saturates the interior while I'm driving.

I am contemplating buying the Holley HP EFI ecu so I wont have to get someone to tune it. I dont want to sacrifice the factory gauges though, but at this point I want it to be finished.

[abecx]

I changed the oil today, fuel smells is completely gone. If you've read previous parts of this thread, I thought it was related to other items. I think the pervasive fuel smell has always been coming from fuel in the oil sigh.

I drove about 10 city miles, parked in the garage, let it idle a bit, no hint of fuel smell. I am going to drive around some more tomorrow, then change the oil again just to make sure its entirely gone. Throttle response is a better after I changed the oil which would make sense if the cylinders were fuel washed I would think. I hope the damage done isnt catastrophic.