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Re: upgrades to my car

Sly, Dennis wrote:
> Carl,
> what do you mean bog factor? do you mean the turbo not spooling up quick
> enough. If so, I was reading the other day a theory about moving the
> catalitic convert closer on a 21/2" to 3" exhaust to create more back
> pressure. What do you think?

> >I know the 5.0 guys can get below 2.0 on street tires, but they're
> >not dealing with the bog factor like we are...I don't think
> >Chris ever got below 2.1 on his drag tires last week.

Maybe it's not a problem for you guys at sea level, but I HAVE to spin
the tires fairly hard or I'll bog.  I think Chris has to spin them
some, too, even though he's got the 86 turbo and the stock flywheel.
The 5.0 guys can get quicker 60' times by not spinning at all, but
I can't.  That's all I meant by "the bog factor".

I think that creating more pressure after the turbo will always be a
bad thing.  We want maximum pressure before the turbo, and minumum
pressure after to get boost the quickest.  Once we have boost, then
we want the minumum possible pressure that will still allow us to
maintain boost before the turbine, too, which brings us back to VATN.
Without VATN, the 0.48 A/R turbo is probably best all around, with
a slight advantage going to the 0.63 for modded motors, and top end

Someday I'll get around to calling Aerodyne and asking them for information
that would pertain to our cars, but if someone else is motivated enough
to do it sooner, go for it...