Nathan-
Might be a bit of a problem, but I bet you can retard the timing a bit
and get away with it. Or run octane boost. You should, tho, cc your
combustion chambers. I found that after a couple of cuts the difference
in chamber sizes can be pretty noticable- this would limit your total
advance to the highest CR cylinder, and probably cost at least a few
degrees/hp...
FWIW
Toby
NATHAN J RUFFCORN wrote:
>
> I just started the reassembly of my 69 2L motor! Seems very straight
> forward so far. My question pertains to the extra compression created by
> having my head cut. After getting the head back from the machine shop it
> has been cut a total of .050 (.025 from each side presumably). This is this
> motors second (or maybe third) rebuild. I am using cam tower shims to keeps
> the timing correct and the chain tight.
>
> Another 2L owner, not of member of this list YET, said his motor, whose head
> has been cut, has severe spark knock. With the changes I have made, is
> this going to be a factor? Is premium fuel usually prefered anyway? I don't
> mind the extra compression as long as it isn't going to affect driveability
> (and ULTIMATELY the life of my pistons :-)
>
> Maybe I'm worrying without cause! Let me know if how your Datsuns have
> reacted to this small mod.
>
> Thanks
> Nathan
>
> 69 2000 (motor going in next week)
> 70 1600 (top going on this w/end)
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