Nitrous Timing

 75 shovelhead with EVO flywheels.Running a 50 hp shot of nitrous.Which
mark on the EVO flywheels will put me close to correct timing?
Thanks,
Buzzurd

 buzzurd wrote:

The 'N'.
--
StT
you're welcome.

kaBOOOM!

 
StT wrote:

OK...so guess this isn't a tech. site....just a bullshit site.Set your
timing at "F" StT.
You figure it out smartass!!!!!

 buzzurd wrote:

First off, I think I'm legally and moral...wait, there's no such thing
around here. Anyway I'm obligated to say that you're supposed to read
the FAQ's a'fore ya post.  But what the hell...

Anyway, I don't think your new flywheels will have any usable markings
for timing your current set up.  I could easily be wrong, but... I
think you're better off starting from scratch and doing it right.  I
can't recall the exact timing set for a shovel, but I believe it was
something like 5/8" (piston travel) BTDC.  You're gonna want to check
that, can't trust my memory.  You can buy/make a guage set that
consists of a spark plug that's been drilled out and threaded to accept
a piece of round-ended all thread. That gig will give you TDC: mark the
threads where you find TDC, then add 5/8" (that'd be 5/8" lower into
the heads) and carefully roll the motor until you hit the stop.  Then
pull the timing plug and (carefully) make a nice deep mark on the
flywheel.  That's your new timing mark from now on.  Or you could just
pull the front head and do it that way.  <shrug> Either works...

So now you've got the right timing mark, but with nitrous, if you're
not using a good programable ignition with a triggered pull-out
(dial-back), then you're gonna have to choose how you set it up: either
it'll run hot and sluggy when you're not on the juice (timing set
retarted for the nitrous), or you risk terminal detonation when you hit
the giggle button (timing set normally).   All this is assuming a dry
set up, diff. rules can apply if you're going with a full-zoot wet set
up.  But for dry system, I'd go with a good programable electronic
ignition with an adjustable dial back, either throttle controlled
(small contact switch on the carb linkage) or wired directly to the
nitrous triggle switch. Good luck either way...

-Kuda