XR274HR-10 in 318

I haven't done anything to the heads yet. I plan on having them ported and adding 1.88/1.60 valves. As far as the compression ratio, I think these engines are rated at 9:1 if I'm not mistaken.

I'm a little skeptical on the converter... I was browsing around trying to collect information and some say it would be fine and that a quality converter would be the best route. Even though my combination is mild, I don't want to hurt the performance in any way.

Are your '87 Roller stock flat top pistons .040 ths down in hole, like this '91stock 318 Roller that is pictured below ? That will be good for your compression.

Can go with the thin Mr Gasket G1121 head gasket too, with a compressed thickness of .028 ths. That will help too.

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