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OEM vs Ebay Head Gasket....

Wez_

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OK, well I know you get what you pay for, but can you tell me what could happen if this head gasket is used. It is advertised as part number 8003. It is a 65mm Head Gasket. OEM head gasket is made of metal layers, solid and secure. New one is basically paper...So fkn sad. Also, the bore seal has a different pattern than the OEM. Please advise amc.


OEM Head gasket fitment.

20170729_115014.jpg


This is the new head gasket fitment.

20170729_115222.jpg
 
Well, I've had some paper ones go a pretty long time....................but I don't care for the too big firering there. Lost compression. Easier to blow out with the bigger rings.

It WILL work, just can't say how long. Looks like a 900 gasket.

Nobody sells like a stock Vesrah head gasket any longer?
 
You could always bore it out to a bigger displacement lol Thats how you do it right buy the big gasket and say Oh look now I have to go big bore lol:laughing:
 
The OEM gasket had a weird pattern around the bore. Even though it's tighter north to south of the bore, it's wider in those corners. If you guys have seen paper gaskets last, then I'll try it.
 
The oem gasket was the shape of the combustion chamber which is why it is an odd shape, the wide spots in all four corners are relief areas for the valves. That larger area from the bigger gasket will also be a place for carbon to build up which could eventually cause some preignition problems from the carbon buildup. But like AMC said you will have a compression ratio drop from the big bore gasket
 
X2, the chamber is actually too big for the 750 bore, they were already preplanning for the bigger bores to follow as the engine was originally envisioned to be expandable to bigger sizes as the years went by.

Original design was the RCB941 endurance road racer which then evolved into the RS1000.
 
Ok, I thanks fellas. I think I understand it now. So the gasket can work, just expect slight compression loss and potential carbon build up in the expanded area.

Should I clean the domes of the pistons/deck before reassembly?
 
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