This is an olde subject that I'm rekindling now. What is the working
pressure of the PI metering unit? I seem to recall that the injectors close
at about 80psi. What is the minimum needed to run them at 6000rpm's?
I've got a gauge connected to my pressure line at the pump relief valve and
get a drop to about 90psi @ 5000 rpm's and can't hardly see 6000 rpm's. I
think this is a fuel pressure problem as I've checked timing, ignition and
metering unit and that seems to be okay. I've got plenty of vacuum @ idle
and can richen it up easily via the choke cable. Could this also be the
maximum fuel adjustment?
I'm still running a Lucas pump and I show 120 psi when idling and cold, the
pressure drops a little as the fuel warms up. When I accelerate the
pressure starts to drop to about 100 psi and as I get to 5000 rpm's the
pressure drops to about 90 psi. Any thoughts or ideas? I'm looking at
going to the Bosch pump, but I also want to make sure this is the right area
to focus.
Thanks, Charly Mitchel
TR6 #44
----- Original Message -----
From: "Terry and Cindy" <Roadandtrack2@hypermax.net.au>
To: "fot" <fot@autox.team.net>
Sent: Thursday, June 09, 2005 4:13 PM
Subject: RE: Tr6 PI and racing
> We have used Lucas PI on race cars since it was new. I have experience
> with them on outright formula race cars and triumphs
>
> The system off a TR6 or 2.5PI is fine up to a point. The biggest problem
> you will have is the pump. Lucas PI pumps were great when new, but are
> now mostly stuffed. We use a bosch pump but they produce such pressure
> when loaded , that they destroys the TR relief valve. We run 2 modified
> Lucas valves in parallel. The other hassle is that in other than flat
> out use, there is a lot of hot fuel being returned to the tank. If you
> live in a hot are, you will need a fuel cooler in the line. Also, don't
> be tempted to run a small tank, as the fuel gets too hot.
>
> The vacuum control unit is biased to "nice" road car use. For race use
> find a "snail cam" arrangement and ditch the vacuum controller. These
> were fitted to all the proper Lucas race systems and can still be found.
>
> The Lucas bung seals in the metering unit will not handle many types of
> modern unleaded fuel without stuff up. Test one in a sealed jar of the
> petrol you use for a few weeks
>
> We have not found much improvement with lengthening the intakes , but
> have proven they like a very long snorkel with cold air intake feeding
> the plenum box. Basically, the longer the better
>
> A couple of local racers have converted their system to full electronic
> with a single throttle body, but none of them have ever found meaningful
> power increases as far as I'm aware
>
> Terry
_______________________________________________
http://www.team.net/donate.html
Fot mailing list
Fot@autox.team.net
http://autox.team.net/mailman/listinfo/fot
|