Misleading?? Shane, nothing against you here...but i've installed Paxton,
Vortech, ATI, and Powerdyne's on many vehicles over the years and have never
seen any problems on the daily street driven vehicles at all. As long as the
auxilliary fuel system was installed properly, the fuel enrichment works just
fine. On the Powerdyne, in this specific case, the FMU plate can be adjusted
from a 4:1 - 16:1 depending on the modifications. From what Shawn described,
it's nothing that the PD FMU system can't handle.
On the "Big Boys" who use seperate controllers, yes...there is a big difference
and tuning is required...depending on the type of system they're using. Larger
injectors, timing curve changes according to rpm and boost, fuel pressure
changes, etc. But again, the systems available to the regular "walk-in"
customer are more than adequate for what most are doing. (Those with the 12-
second and quicker vehicles will obviously require some extra tuning.)
I'll use my truck as an example (V8's should stick to the 12:1 FMU plate right
from the start and prefer 24# injectors):
(1) Powerdyne w/6# Pulley, factory injectors (or FMS 19# High-Flow), 48mm V8
TB, Headers, Exhaust, Ignition, and mild intake "cleanup": 10:1 FMU w/no retard
required.
(2) Powerdyne w/9# Pulley, FMS 24# injectors, 50mm Billet TB, Headers, Exhaust,
Ignition, and mild intake "cleanup": 12:1 FMU, ICON custom curved to retard
in .5 degree increments (up to 3 degrees total) from 2200-5500rpm.
(3) Powerdyne w/10# Pulley, FMS 24# injectors, 50mm Billet TB, Headers,
Exhaust, Ignition, and mild intake "cleanup": 12:1 FMU, ICON custom curved to
retard in .5 degree increments (up to 3.5 degrees total) from 2200-5500rpm.
- Bernd
> bernd@texas.net wrote:
>
> > With the fuel curve, most of all the Supercharger kits come with a fuel
> > enrichment circuit of some sort. Leave the fuel enrichment up to the
external
> > systems (FMU/Pump, Boost-A-Pump, etc.). They control the enrichment under
all
> > conditions and only under boost.
>
> Thats a little bit misleading tho because whenever you increase the boost by
> changing pulleys, open up the breathing by porting heads, going w/the new RT
or
> ported aluminum heads, larger throttle body, headers, etc. you will again be
on
> the lean side where you need to manipulate the fuel delivery curve. None of
those
> external systems will compensate for that. Thats why the big boys use real
> controllers - you know where you are actually in control - not at the mercy
of
> someone else's expected outcome.
>
> Latr,
>
> Shane
>
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