injector resistance

[Gary Derian]

I think Robert said, and I agree, that at part throttle VE is not important
(VE schmee E), economy is.  The last year for turbos in F1 were restricted
by fuel consumption limits, not max power so the Honda guys were designing
for the rules.  They could always run a little more boost if they needed
more power while maintaining fuel temperature for max. economy.

Before the fuel economy rules in F1 the 1.5 liter engines were running 60
psi (all you can get with a single stage centrifugal compressor) boost and
getting 1200+ hp.  With the fuel regs, I think they were down around 700 hp
or so.  Thats why they did not worry about VE.  I  think they also had a
thermostat in the intercooler to not overcool the intake air.  Again, they
were designing for economy, not max power.  I don't remember the exact
numbers but I think the specific fuel consumption was down below 0.40 lb per
hp-hr.

On a street engine with a turbo, you can usually boost enough to blow the
crank out of the block.  Designing for fuel economy seems like a good idea
here, also.

Gary Derian <gderian at cybergate.net>



>Robert Harris <bob at bobthecomputerguy.com> writes:
>
>>> If it ain't vapour it ain't agonna burn.  Period.  See laws of physics -
>
>combustion section.
>
>Ideally, for maximum power, fuel "droplets" will enter the cylinder
>under their
>boiling temp, having absorbed the maximum heat from the mixture possible
>(thereby making it as dense as possible), and will then completely vaporize
>
>after the intake valve closes and prior to ignition.
>
><<
>
>I agree with you 100%. But Gary said "vaporize coming out of the
>injectors." That would reduce VE unless it was direct injection and I was
>wondering what Honda was thinking. I know Honda's engineers know what
>they're doing, just wondering what they're up to? There is a lot of R&D in
>the racing world to minimize the vaporization of fuel upstream of the
>intake valve and now Honda is doing it on purpose....they must know
>something the rest don't.
>
>!^NavFont02F02DB000EMGoHGxMH6AHIDD0921
>
> -- Michael Baxter, MBaxter at Compuserve.com
> http://ourworld.compuserve.com/homepages/MBaxter
> From Reno, NV USA on 13-Jan-1998