Reply to "Weber IDF's and Panteras"

I have posted this in a similar thread some time ago.
But here it is again.
A different take on the Weber look, using injection.
My Pantera runs fuel injection, 8 x 48mm throttle bodies.
Similar set up to Weber’s & a similar look.
This is an old “Pantera Performance center” kit I found on Ebay.
I assume from the 1980’s.

Velocity stacks I custom made, they are in two pieces where the top screws on to clamp in place a stainless mesh screen.
I have run the car with & without the screens on the Dyno & it made zero difference to the tune or power output.
Not that was easily noticeable anyway.
Computer is a Motec with crank angle sensor, TPS & MAP sensors only.
I rebuilt the throttle bodies & re-set the butterfly clearances.
Runs really nice, easy to start & reliable.
Combined with the 11:1 CHI 4V heads it made more responsive & snappier power.

I don’t run the car in the rain, nor do I wash the car with water.

The only issues I have had is balancing the throttle bodies to make sure they are all breathing the same amount at idle.
Also, because of the high air flow of 8 x 48mm butterflies it requires a corresponding amount of fuel when snapping the throttle open from idle.
So running rich at idle was causing the spark plugs to foul.
Re-tuning the car at idle & leaning off the fuel didn’t work, it simply backfired.
So now I have changed the Spark plugs from NGK BCP6ES to a hotter BCP5ES.
Yet to try it & see if it has cured the plug fouling problem.

The other issue is that each throttle body has its own return spring. And they certainly are required to get the butterflies to snap closed.
But combine the tension of 4 x springs & it makes a very stiff throttle pedal.
So at some stage I’m going to have to look at a progressive throttle linkage to gain some more leverage & better throttle control.

In regards to Vacuum.
I run an 8” dual diaphragm booster as my master cylinder is 1 1/8” bore, (4 piston rear calipers).
I also run a vacuum bottle up front with an extra check valve.
I tried supplying vacuum from one port & it was no where near enough.
So tried 2 ports, still not enough.
Then went to four ports & that was sufficient.

regards,
Tony.