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948 head questions

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I

ichthos

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I need some help on my Bugeye 948 head. In a previous thread I mentioned how antifreeze was leaking between the head and block. I am not sure what I did wrong, but it seems like the most obvious choices for me to go after are the head and head gasket. The head was rebuilt, but I do not know if it was surfaced. Can a machine shop surface this with the valves in place? My second question involves the head gasket. Can someone recommend a head gasket and source? Moss offers a number of head gaskets-can someone tell me the difference between the higher priced head gasket "sets" ($40) and the lower priced head gasket ($12) Thanks for your help as always.
Kevin
 
No matter which gasket you get just be sure -like someone already said- to get the gasket for the "small bore" engine (948-1100).
The 1275 one WILL leak on a small-block engine.
Since you are not going to be racing your car I would think that any head gasket will be fine if the head & block are flat. The really expensive one isn't necessary (my opinion ONLY).
BillM
 
And yes the head can be surfaced with the valves in. Don't even think about the block, it's an engine out job.
 
I would consider testing for cracks in your head. Let a machine shop go completly through your head, the expense will only be labor if valves have been done correctly. Get it all done no doubts!!!!
 
Kevin,
I would get the higher-priced spread gasket kit, and I would ask if it is a Payen. I think thaey are the accepted better quality spread as head gaskets go.
Scott in CA
 
I guess I make too many assumptions, of course have the head checked at an engine shop. This is insurance time.
 
Second on the Payen gaskets. Also, checking the head at a good machine shop. The 948/1098 gasket should show a Part # of AF070 or AF070N for non-asbestos.

Also check your head nuts/studs and the threaded holes in the block. Make sure the threads aren't pulling out/off.

All heads and blocks "cup" in the center (side to side) due to thermal cycling. I've had race 1275 blocks drop 0.002" after a couple race seasons. Not good for keeping 14/1 compression in each cylinder where it is suppossed to be.

Make sure your rocker setup does NOT use the aluminum pedestals. These won't take much torque and are very problematic.

HTH
Mike Miller
 
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