Mr Helmholz - simple model

[Todd....!!]

Gary,

All good questions, don't really know the answer, may try the high temp
paint deal when at the track next time and let ya know what happens
between usin the high temp vs the regular Krylon type spray paint..

As for rpm's, ya just paint the tube bolt it on, go thru the 1/4, check
the tube for where it's burnt, maybe try it a couple different
times...just to be sure, then cut the tube...

The rpm's aren't held constant unless you have some sorta newfangled
clutch setup like the top fuelers have that hold their rpm's at PEAK
power the whole run!  THAT would be nice!!

The throttle position IS held constant however, at WOT, that is....

LATER....!!

Todd....!!

Gary Derian wrote:
> 
> Doesn't cutting the collector change the standing waves and therefore the
> place where you want to cut it.  Maybe an iterative process.  I have no
> technical explanation  for this either.  I don't know why pressure waves
> would cause the paint to burn.  What if you had high temp paint that didn't
> burn, or low temp paint that burned all over?  Do you have to hold a
> constant rpm?
> 
> Gary Derian <gderian at oh.verio.com>
> 
> > I have heard exactly the same for an H-Pipe.  Paint it, and where the
> paint
> > has blistered up is where the crossover needs to go.
> >
> >
> >
> > >The way I was taught to roughly but effectively 'tune' my exhaust system
> > >on my 4 stroke v-8's engine's is to bolt about a 2 or 3 foot pipe to the
> > >header collector paint it black with some spray paint (preferably BEFORE
> > >installing the pipe) then do a run down the strip...
> > >
> > >After runnin the car at WOT for a 1/4, there will be a point on the
> > >'tuning' pipe where the paint has been burned off, and a point further
> > >up towards the header where the paint isn't burnt at all!
> > >
> > >At the point where the paint begins being burnt is where ya cut the
> > >pipe.. Whalaa instantly tuned exhaust...
> > >
> > >I've never heard a technical explanation of why this works or even if it
> > >helps or hurts or is just a guess at the correct length of exhaust
> > >pipe...
> >