The next thing on this re-rebuild is my block has been machined for O rings but has been skimmed afterwards so the groove is no longer deep enough. I have been told it is pretty hard to remachine that groove to suit. So my quesition is can I run a oringed block with just a normal headgasket or is it a disater waiting to happen[xo]

Unless you remove it totally Luke I would run the oring, that would mean remachining it. A mate has just been faced with the same issue on a 200 block. A good machinist can easily remachine the groove, we are currently running .012" protrusion, just debating whether to reduce that to around .008" and use a YB0611 gasket.

I might have to have a chat to a few machinsts then Phil. I have .015" proud at the moment was going to take it back .005" and use the same gasket. what's the best gasket with o rings then. The pistons on your mates motor have they got valve reliefs?

Hi Santa,

Were looking at running the YB0611 with the orings but had issues with coolant leakage under the gasket when it was changed prior to the rebuild. I have also heard of using the YB1261 gasket but am still to hear from someone sucessfully using one with orings and who can advise the protrusion they set it up with.

My mates pistons are new Cosworth Racing pistons so have valve reliefs along with all the other goodies.

Cheers,

Phil.

A very good read here

http://www.moparmusclemagazine.com/techarticles/engine/mopp_0108_isky_groove_o_matic/index.html

What piston to head clearance then boys? What gaskets are you basing this on?

40 thou gasket - 15 thou = 25 thou?

Hi Lincoln, these numbers are relating to wire ring protrusion rather than piston to head clearance

Thanks [:I] I know nothing about wire rings. What is the diameter of the wire? Is the ring also in the head?

Hi Lincoln,

The wire is .040" diameter. There is no recieving groove in the head. The theory(old theory prior to MLS gaskets)is to create extra crush on the gasket in order to take higher cylinder pressures without blowing the gasket out. They are more trouble than they are worth these days.

Cheers,

Phil.