[Diy_efi] RE: Diy_efi digest, Vol 1 #413 - 12 msgs

[Dave Dahlgren]

I think you need to introduced to the long straight at Daytona up on the
banking.. No matter how heavy or light your car is you hit the aero wall so to
speak where it is on the floor and she won't go no faster... That is what a
brake will give you and you better be correct at that point. The better after
market stuff has tables and corrections for what gear you are in. You can and
should change timing fueling and boost according what gear you are in as it
compensates for the relative load on the engine.
Dave

Shannen Durphey wrote:

> Using a braking type dyno to tune a car for WOT can produce misleading
> results.  A lightweight car with a high power to weight ratio would
> typically never see the same load and duration that can be applied with a
> brake type dyno.  Running up to a specific rpm and holding that rpm while
> fuel and spark are tuned in will tend to heat parts more than they would be
> heated in "normal" operation.  The consequences can be more fuel/ less
> spark than optimal get dialed into the final tune.  Power may be down, fuel
> consumption may be up, or both can occur.  The inertial loads alone provide
> more than enough resistance to provide an acceptable street and competition
> tune for these vehicles.
>


_______________________________________________
Diy_efi mailing list
Diy_efi at diy-efi.org
http://www.diy-efi.org/mailman/listinfo/diy_efi