Variable Restrictiveness Exhaust - Meet Mr Helmholz

[David A. Cooley]

> This talk of fancy tuning is interesting and certainly improves the power
> per displacement but my question is does all this work actually make a
> better vehicle.  Isn't it easier to just use a larger engine with
> appropriate gearing to achieve the same power and economy without all the
> extra parts?
>
> For sure there is some small fuel economy gain in city driving with a
small
> displacement engine because it uses less fuel at idle.  But in cruise mode
> or WOT, specific power is not really affected by fancy tuning.

There is a lot to be said for proper tuning at WOT *AND* cruise.  I had a
1985 Buick GN, 3.8liter V6, turbocharged and NON-intercooled.  It ran 15.92
at 88MPH stock in the 1/4 mile and got 20mpg on the highway.  I manufactured
a lot of mods myself and bought some others... I had it running mid 12's and
highway cruise increased to 25-27MPG with the A/C on!
A 455 buick big block, mildly warmed over would have gotten me the 12 second
time slips, but MPG would have probably been close to half what the little
V6 was getting... You have to keep in mind that more CI = more fuel at
stoich.  you have to feed what you have.