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Friends I am in a little situation and I could use your help with my 85 Alfa Romeo Spider. I had to rebuilt the engine after the previous owner ran the car practically without water.
I called IAP and ask for piston set and someone (for one reason or another) i ended up buying the 10.4:1. After I installed the piston, and dropped teh engine in the car, I found out that my head was warped and I had to surface it. I end up removing .040" and by some basic (may be wrong calculation) I measured a compression ration in the end of about 11.3:1.

Long story short, the car ran for about 22 miles on a german head gasket purchased at AlfaParts. I had to pull the head out of my engine again, the gasket had burned the metal rings in pistons 2 & 3, and I mean burned, melted, gone !!!

My question to all of you is... is there a "prefered" head gasket to use for the high compression pistons, or any solution to prevent burning head gaskets.
I suppose one could suggest a thicker (may be two gaskets one on top of the other), but is there a more reliable gasket for high compression?

Thank you much for your help (in advance).:D:D
 

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Much MUCH easier to cut the tops of the pistons, OR use another head. One of my major complaints is CUTTING WARPED HEADS. They can be pressed flat by one skilled in aluminum head repair. Moreover, if it is really warped, what do you suppose happened to the cam journals? They are STILL warped! Now the head is cut to the valve seats, the combustion chambers are too small, and the journals are out of line. You have a trashed head. Hope this helps.
10.5 /1 can work ok with good pump gas. Not much more though!
Gordon Raymond
 

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Gordon thank you for your input. I must tell you that I have checked the Cams on the bench and they are very very straight. The issue is not as much as how bad is the head, but for that given compression, I am searching a reliable head gasket. I am wondering what people use in their racing Alfas.

Thanks for ....comments.
 

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My motor is set up exactly the same as yours - 10.4:1 Borgos with the head shaved .040. PO shaved it, not me. :) I'm using an early, NOS Reinz head gasket WITH the adhesive, and the best 93 octane pump gas I can get. I've put over 2k miles on it since the rebuild. The head gasket is holding up nicely so far (knocks furiously on wood), which tells me there's probably something else that is causing your problem. Maybe your head is toast as Gordon suggests, or maybe it's something with the original damage, or with the rebuild, or who knows what else. I wouldn't blame the head gasket. There are copper gaskets for racing, but I've heard they tend to be pretty messy for a street car.

Good luck,
Jason
 

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Discussion Starter #5
Jason, thanks for the input. I am curious what info do you have on the Copper gasket.How messy are they for the street car, and how so.

My head gasket is Reinz as well and let me tell you, the metal rings (sleeves) around piston 2 and 3 are completely chewed, and in same cases ...gone.
I suspect my car is running a little rich in fuel mixture, that may have something to do with the problem. But I also notice that the reinz has very little metal sleeves around the bore. Who knows..... could be a million and half things.. but i am serching for info on the copper gasket.

Do you hear any knocking noise (at any rpm) I didn't. I must say i was cruising on a freeway, and was going fine and suddenly something gave because right away I saw white smoke on the tail ......
 

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I have no experience or expertise with the copper head gaskets. I looked into it because I was concerned about the high C/R on my engine, and read here on the board that while the copper gaskets seal compression very well they don't do as well with fluids. Here's one reference: http://www.alfabb.com/bb/forums/showpost.php?p=271746&postcount=10

I don't hear pinging, but once again I'm pretty conservative on the timing and don't push it too much. My current strategy is to keep a known good spare motor in the garage, on the theory that as long as it's there the high C/R grenade will hold together, but if I'm ever without a spare it'll go nuclear on me for sure.

Good luck,
Jason
 

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Were the threads on the head studs and nuts cleaned properly before re-assembly? You can get completey wrong torque readings if there is crap on the threads. I run a tap and die through mine every time. I did not always do that and I paid the price with a blown head gasket in less than 20 miles.

Ed Prytherch
79 Spider
88 Verde
 

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Consider replacing the head. Used ones are not expensive and readily available.
Aluminum motor components - water = latent problems.
 

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Alfa head and piston work.

Hi Alfa-Born,
Here is the type of things that happen:p. Lets suppose you have ONLY high compression on a motor with carburators. Ignition is correct, and mixture is correct on all 4 cylinders, plug heat range is correct not using an extended reach plug. All combustion chambers are the same volume (cc'd) and valve timing is correct. Fuel is pump,about 93 RON.
First you will notice at low engine speeds, a rattle, much like piston slap. As engine speed increases, this may SEEM to go away:rolleyes:, but detonation is still doing its work. Upper rings may break apart. If there is a high spot, carbon, or a rough area on a piston, that area will become hotter, until it melts, blowing a hole through the crown of the piston. If pistons are cast, they may fracture, either with cracks, or come apart:eek:.
Now to your problem;). The Victor/ Reinz is a very high qualty gasket. Gasket failure is fequently not related to high compression or detonation. The Reinz fire rings (the part that went away) are stainless steel. If the fire rings extend into the combustion chamber, for any reason, they will form a hot spot and burn up:(. Also if they are not sealing correctly due to a low or other high liners, or a warped head, OR A HEAD MILLED AT AN ANGLE:mad:, they will burn. Lean mixtures, not rich, cause detonation, and damage. A cylinder or two with an air leak on the intake passage will lean the mixture and cause detonation damage. With known, too high compression for fuel available, a rich mixture can help keep the engine together. Most power (and heat) is generated at a correct mixture, heading toward lean, the danger zone! :eek::eek:
So, if only two fire rings went away, and they appear melted, they were the hot spot:cool:. Could be due to any of the above causes. As John mentioned above, at the moment, a used head can be an inexpensive cure. Feel fortunate it is not a GTA head, 750 veloce head, 1600 head, or one that has lots of money in it in runner, port, valve, valve seat, and combustion chamber work! These are NOT inexpensive:cool:.
With a replacement head, measure it to be sure it is stock height:). If the assembler really wants too, only a skim cut, to clean it up. If it is not flat,
have it pressed flat, by one that does this work with high dollar aluminum heads!
Then... you can run 10.5 with pump gas IF the other things mentioned above are all correct, and your Reinz gasket will be just fine:cool:! I hope this helps. Best, :DGordon Raymond
 

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On the cost of replacement heads: IAP pay $250 for good core Bosch heads, so that is probably the market value. On the other hand, I sold a complete, good Bosch engine for $350 earlier this year. If you can find someone local who is parting out a Bosch Spider, then you may get a good deal on a motor as hardly anyone wants to ship one and it is a buyer's market.
Ed Prytherch
 
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