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Posted by: Blynes Mar 3 2003, 06:26 PM

I need a pair of cylinder heads for my 2.0 litre 914.

Can anyone help point me in the right direction?

Posted by: Brad Roberts Mar 3 2003, 06:51 PM

Where are you located ??

I may have an extra set without cracks in the exhaust port.. I'll ask 500$ for the pair if you dont locate another set.

B

Posted by: Dave Cawdrey Mar 3 2003, 10:41 PM

Does that mean there are cracks elsewhere, B ? lol

Fair price, btw. Paid 450 for my set. Then 560 for rebuilding. Worth every penny

Posted by: Brad Roberts Mar 3 2003, 10:48 PM

Typically 914 2.0 heads will be cracked around the spark plug holes.. but this isnt (never has been) a issue with repairing them. So far (too this date) I have never seen a 2.0 head where the exhaust port cracks have been repaired. I have heard rumors about people repairing them, but never seen it completed.

B

Posted by: Alfred Mar 4 2003, 01:00 AM

Posted by: Dave Cawdrey Mar 4 2003, 01:21 AM

Northwest Connecting Rod Service
1705 South 93rd Street, Seattle, WA 98108
(206) 763-2487

Excellent service. My case was finished today. Give details soon...

EDIT: Typo on my 1st post, 560 for rebuild, not 500. They did a shit loada work, tho

Posted by: Dave_Darling Mar 4 2003, 02:08 AM

Man, those peen marks around the valve seats make me nervous...

B, you have indeed seen heads with welded up exhaust port cracks. I think you've even seen the car running with them. The previous ones on my car had that done.

--DD

Posted by: Brad Roberts Mar 5 2003, 02:27 AM

I have personally only seen your car twice and it only ran once out of those two times.

Maybe that is why it dropped the seats "again". They tried to weld them.

I should have said... I havent seen any "off" the car before install.

B

Posted by: Brad Roberts Mar 5 2003, 02:29 AM

I was concerned with his peen marks also. Your begging for detonation. Each one of those is a hot spot waiting to happen. I cant prove my theory, but you will never see that in a race head.


B

Posted by: Dave Cawdrey Mar 5 2003, 02:39 AM

Thats the way that "Race" guys does his staking. He builds TIV race engines all the time. VERY reliable. I feel fine about them :finger2:

Posted by: Brad Roberts Mar 5 2003, 02:48 AM

My personal opinion: (which I happen to share frequently) He doesnt have the proper equipment to install them without doing this. I'm sure (100%) that he knows what he is doing. I'm not quite sure what he gained by doing this. If heat wasnt an issue, then I could see this working no problem. Right this minute I'm not 100% convinced that this method is worth doing.

Have him come to the BBS and tell us why we should all be doing this (convince me) if he has time. I'm sure he would benefit from teaching us a few things.


B

Posted by: J P Stein Mar 5 2003, 03:08 AM

IMO, a better way would be to use a center punch
around the periphery about .08 (WAG) out from the seat. Then grind the "volcanos" flush. This would be a swedge rather than a stake. Both methods are viable, but I doan like those thin "splats" of metal in this context.

Posted by: Bleyseng Mar 5 2003, 09:36 AM

Brad, Jerry is not a 'puter guy just a racer/machinist. I am running heads he rebuilt but they seats weren't done like that. He did the port work simular to how you said to do it. I can't say I am excited about the staking either as it seems it would cause hot spots.
Geoff

Posted by: Alfred Mar 5 2003, 12:25 PM

I have a somewhat related question. After the local VW dealer installed helicoils in my 2.0's spark plug holes I noticed that the sharp end of one of the helicoils protruded slightly into the combustion chamber. Is this likely to cause pre-ignition? (I vaguely recall from my tech school days that any sharp point in the combustion chamber will glow red and cause pre-ignition).

Alfred

Posted by: J P Stein Mar 5 2003, 02:26 PM

As a general rule, your right, avoid sharp edges in the boom room. This is much more af a problem in a higher compression engine, one bumping up against
the octane limits of what ever your using.

Assuming stock compression (in your case), I wouldn't take the engine apart to fix it.

My objection to Korijo's heads is more theoritical than practical, i guess.

Posted by: Alfred Mar 5 2003, 02:58 PM

Thanks JP.

I looked through my old textbooks and found the following information.

"... Detonation can be caused by an excessively high compression ratio or by a low grade of gasoline. An overheated valve or bit of carbon, etc., can ignite the 'end gas' and cause the formation of the second flame front".

"Preignition is caused when a glowing bit of carbon, an overheated spark plug, etc., ignites the fuel charge before the spark plug fires. When preignition occurs, the premature explosion attempts to drive the piston down against the direction of rotation".

Alfred