DUhhhh... I guess I won't write so many late night letters. :-)
This is about me doing a compression test with the exhaust valves
inactivated.
Larry wrote:
> Intake stroke - Intake valve opens, piston sucks in air/fuel mixture. Intake
> valve is open.
>
> Compression stroke - Air/fuel mixture is compressed. Both valves closed.
>
> Power stoke - None here, no spark. Mixture expands back out. Both
> valves closed.
>
> Exhaust stroke - Since your exhaust pushrods are gone, this is yet
> another compression stroke. Exhaust valve should be open, but isn't, so
> both valves are closed.
>
> Intake stroke - Intake valve opens near TDC so piston can suck in more
> fuel/air, right? But remember, the exaust stroke was actually a
> compression stroke, because the exhaust valves never open. So as
> soon as the intake valve opens - *POP* through the intake, since
> the fuel/air mixture is still highly compressed.
>
> Am I missing something???
Nope. This sounds very likey. I just left part of the equation out
of my head. Oh well. It was fun anyway. :-) I need to theorize just
a bit more before perfoming the experment. Doh!
> >to set the intake valves opening later. e.g. retard the cam. If
> >anything, I'm getting an education!
Yup, and the tuition is getting higher all the time... :-) However,
if I do decide to move the cam timing, I think I'll retart the cam.
That should make it idle better. (I think)
TTFN,
-Scotty
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