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Im pretty sure I got detonation due to bad gas. AFR's were good and boost was holding steady. The stupid thing is I heard detonation, it just took me too long to figure out what was going on.

Bringing the head to a machine shop wednesday or thursday to get checked for cracks and warping.

Cylinder walls dont look that bad. Slight scoring on a couple. Im gonna try a gasket and see what happend










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Ouch

How much boost? Cracked ring lands are a possibility.

It was only about 10 psi.

I bet all sortsa broken shit is possible after that much stupidity. Pretty much just gonna put a new bmw gasket on it.

Are JE pistons pretty tough against detonation?

If its not freezing cold out the next couple days ill try n pull the pan off n pull some pistons.

If the pistons r junk then this car will likley be going into the garage for a long while.

Don't go any deeper just put the head gasket on and retard your timing if your sure a/r is right. I went thru 6 hg in 6 months,so your not alone.
good luck
marc

bad way to start the year,i would oem gasket it too, but not with out straight edging the top of the block . good luck, i like using the high temp copper adhesive spray on oem gaskets,my personal prefernce and increasing tourque by 8-10 lbs, but thats me

Copper sprayed stock gasket and bolts.


You got studs? Can the metal gasket be reused?

marc79euro645 wrote: I went thru 6 hg in 6 months

Holy crap that's a lot of HG.

JE pistons are tuff and can take a beating, if you had broken ring lands the engine would burn oil. Looks like too much timing, plus the headgasket looks fairly new?
Take the gasketgasket apart, clean all surfaces, spray all surfaces with copper spray reinstall, torque the ARP's to 90ftlbs.
B34 block right?

Well the engine atleast lower end only has about id estimate 13k miles on it(replaced the cluster so many times who knows anymore).

It just looks so burnt on those edges I wouldn't think it would be reusable.

Yes, im using ARP's.

B34 block and head.

EDIT: I'm just gonna goto the closest BMW dealer at lunch today and order a gasket. It's $124 for the thicker (+3mm?) one so that's a price I can live with. That and I think spending money I don't have will teach me better lesson.

I'm going to do a cylinder leak down test after it's all back together. Would give me an idea if ring lands are broken and how quickly I should save money for a new engine.

jim325 wrote:Well the engine atleast lower end only has about id estimate 13k miles on it(replaced the cluster so many times who knows anymore).

It just looks so burnt on those edges I wouldn't think it would be reusable.

Yes, im using ARP's.

B34 block and head.

EDIT: I'm just gonna goto the closest BMW dealer at lunch today and order a gasket. It's $124 for the thicker (+3mm?) one so that's a price I can live with. That and I think spending money I don't have will teach me better lesson.

I'm going to do a cylinder leak down test after it's all back together. Would give me an idea if ring lands are broken and how quickly I should save money for a new engine.

If the headgasket looks burnt deff do not re-use.

jim325 wrote:Well the engine atleast lower end only has about id estimate 13k miles on it(replaced the cluster so many times who knows anymore).

It just looks so burnt on those edges I wouldn't think it would be reusable.

Yes, im using ARP's.

B34 block and head.

EDIT: I'm just gonna goto the closest BMW dealer at lunch today and order a gasket. It's $124 for the thicker (+3mm?) one so that's a price I can live with. That and I think spending money I don't have will teach me better lesson.

I'm going to do a cylinder leak down test after it's all back together. Would give me an idea if ring lands are broken and how quickly I should save money for a new engine.

I wouldn't go with a stock gasket on an M30, studs or not. You'll be in there again. TCD can get you an MLS for a good price, and if your tune is good it'll hold 20 psi. The stock gasket will never do that.

Many people have done that what are you talking about; you use orings

Just saw one recently. Stock gasket with orings. Still blew at low boost.

An MLS is stronger than an oringed stock gasket. The stock gasket will yield at "XXXX" psi. The orings can only support the stock gasket when it begins to budge. The MLS will not fail, but at some point the head will lift/deform like it did here.

I blew an mls too. I use an e34 m5 headgasket with copper spray and arps to 85#.
marc

This really bums me out. I wish I could figure out how to make a reliable knock sensor that would work with noisy M30 valve train.

I probably need to revisit it now that some new conditioning hardware is available.

Yes

So finally got the cylinder head done. They had to take. 008 of an inch out of it. Im not sure but that seems like a lot?

So the head is warped?

Yes

Is the head still within spec thickness?

I'm not sure. I don't have the proper precision measuring tools to check it. Nor can I find my 5 series service manual to know the specs.

In other news. The BMW dealer I ordered my parts from had told me they would be in on the following monday. I ordered them the 27th of december, a thursday. I had my gf go pick up the dowel pins and other odd stuff because last time I had called they had said everything was in but the headgasket. So she goes there and apparently nothing is in. It's all backordered and won't be in till the end of this week if im lucky. Really wish they had told me that when I ordered them...

I ordered an MLS gasket, .080, on thursday anyway in hopes that it would be here this tuesday. I called about 4 places before I found a company with 1 actually in stock. But now that not even my dowel pins have arrived, after being told they did, it doesn't matter if I have the headgasket or not.

GGRRRRR... F U bad parts department!!

Head is still in spec. You can see a little divot (actually I see 4 in that picture) that, when absent, indicates when the head has been machined too far. 0.008" is not a bunch, but it is enough to make a difference. I went well past that on an M20 head (0.040") but that was purely intentional.

Finally got my head gasket but im having a little trouble getting the timing right. The o|t mark on the crank pulley is lined up with the mark on the timing cover but the cam isint wanting to line up.

Is there a chance the chain is kinked down by the crank and not letting it spin correctly? I have zip ties on the cam sprocket and chain that I put on when I took it apart so that shouldnt have changed.

Nvm. Did the first round of torquing studs and cam lined up perfectly. Should be running by 3 if I dont freeze first.

You know I would ask....what is the RA of the surface?

It HAS to be below 50 and preferably below 20.


The surface you see here has been measured by a $3,000+ Profilometer. It is a 16 RA. Yes, a 16. A stock head from the factory is between 45-55 RA. To review why the RA is so important to a FI engine with a MLS head gasket, look here - http://www.mye28.com/viewtopic.php?t=29 ... ead+gasket

http://www.mye28.com/viewtopic.php?p=218728#218728

I cant really answer what ra it is. I told the guy that I took the head too that I was putting a cometic mls on and the ra needed to be smoother than 50 and he said " better than 50 is no problem.

This guy was recomended by everybody I asked. About 6 people. So I trust his abilities.

jim325 wrote: I told the guy that I took the head too that I was putting a cometic mls on and the ra needed to be smoother than 50 and he said " better than 50 is no problem.

Well, you told him what was needed. Thats about all you can do.

It lives again! Ill let it warm up, fully bleed the cooling system n take it for a nice easy drive and see how it does.

Well. It starts and runs and seems to drive ok but it smokes so I assume there is piston damage. I suppose ill do a compression test. Maybe give me an idea how long it will last.

I am burrowing a truck but not sure how long illhave it. Hopefully I can find an affordable short or long block pretty soon.