thor's hammer ignition and mileage

[Bruce Plecan]

> I am currently having some mileage problems with my new engine.  I burned
a
> new chip with the proper 713cc/cyl instead of 784.  Everything on the 350
is
> the same as was on the 383.  Same cam (degreed straight up and dead on)
> heads, int, exh, compression, Ign. timing, etc.  Just smaller. 355 not
383.
> Anywhoo, before at 70 mph I was at 2350 rpm, 15% throttle, 1.86V map.
127-129
> INT. Light accel up a hill on cruise brought me to 2.25V map.  Now a 70
mph
> cruise takes 19-20% throttle and 2.20V map.  slight accel raises me above
3V
> MAP.  still 126-130 INT.

While at a glance you might think things are the *same* you've changed
everything.   Your now at what I mean about no too seemingly identical
engines being the same.
Thou that drastic of difference would kinda clue me that there is a
mechanical problem.
Do you have the TPS Voltages?.   I just have looked at them that way
forever.
I'd imagine 1.0ish would be a good number (thou varies with aero load)

>   My mileage sucks too because of the increased load or something.  The
only
> thing I can think of being different is that before I used RC12YC plugs
> gapped at .050, the new ones are gapped at .035 out of the wrapper.  I
have
> an accel 300+ and hot coil, so I guess the only thing for me to try is to
> open the plug gaps.

As you approach .1" plug gap it can make a  huge arsed difference in the
timing reguirements of the engine.  ie less.   Trouble is it's a hellva load
on the secondary components (even DIS).
Bruce


I couldn't find a leak anywhere.
> Can anyone help me out.  I talking less than 10mpg, and that is no fun.



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