BLACK XR6-VCT

I was going to post this a while back but forgot...

At a recent XR6T Dyno day in Bayswater, I got my VCT on the dyno
and it dynoed at 142 rwKw's. My car is on LPG, so for the second run I decided to play around and remove the LPG mixer from the intake pipe.
(I taped up the hole with tape nicely).

Now the funny part is that I expected more power, since the mixer
nearly halves the intake diameter of the pipe.

Anyway, I lost 4 kw's - amazing.

The guys at the dyno were scratching their heads, and one of them said that I should have reset the ECU to be fair to the test, since my A/F ratio was what was suffering. Anyway, my conclusion is that intake modifications ie. trying to get more air flow into the engine, seems to me to have little (if not the reverse) effect !!!

Any thoughts taximan and others....

__________________
Wheels: 17" Series 1 XR
Exhaust: VCT with no resonators & 3" mandrel from mufflers back, dump pipe
Pacemaker headers (Waste of money).
Air Intake: T-Series, K&N Filter.
Brakes: Calipers painted red, DBA slotted rotors & Lucas pads.
Windows: Tinted.
Gearstick: Shortened.
Fuel: Dual Fuel.
Dyno: 143 rwKw (Dynodynamics - shootout mode).
Heathcote: 15.87 @ 89.1 Mph.

EFFalcon

fwoah
thats weird.
surely most cars wouldn't do that!

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1995 EF II Falcon GLi: Heritage Green, 4spd Auto, AUII 17" Rims, Custom BA Front Bar, Lowered, Gas Research LPG, Clear Indicators, JVC MP3 Headunit, Phoenix Gold 6.5" Splits, Coustic 481QE Amp, Clarion 12" sub, Leather Seats, Power Window Conversion, 3.45 LSD, Pacemaker Comp Extractors, 2.5" Exhaust, Mandrel Bent Intake, High Flow Filter, Wade 1004 110 cam.

In Progress: BA XR Side Skirts, BA XR Rear bar, BA Shifter Handle.

taximan

Only thing I can think of is if you restict air down to 40mm at the gas mixer the air would have to be forced in harder eg.like a garden hose there is no pressure when you connect to tap until you fit an attachment like a spray nozzle then you have pressure so it should be the same for air, a large volume of air forced through a smaller opening should make the car go harder.
Hows that for a theory,am I wrong or right?

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AU series1 Futura Duel Fuel,ceramic coated Pacemaker Headers,Hi-Flow cat.2.5in. exhaust,T-series snorkel,K&N panel filter,D.B.A.Slotted Rotors

BLACK XR6-VCT

Interesting theory....

The only way to prove this, would be to put something simmilar
on a non LPG vehicle's intake pipe and watch the dyno results.

I think that my results may have been different if I had reset the
ECU by leaving the battery disconnected for a while...

__________________
Wheels: 17" Series 1 XR
Exhaust: VCT with no resonators & 3" mandrel from mufflers back, dump pipe
Pacemaker headers (Waste of money).
Air Intake: T-Series, K&N Filter.
Brakes: Calipers painted red, DBA slotted rotors & Lucas pads.
Windows: Tinted.
Gearstick: Shortened.
Fuel: Dual Fuel.
Dyno: 143 rwKw (Dynodynamics - shootout mode).
Heathcote: 15.87 @ 89.1 Mph.

LTDHO

The loss of power could be from a change in conditions in the day or the different running temp. Also the ECU would have been adjusting it's self for the air flow difference. It would need to re-adjust it's self.

__________________

BLACK XR6-VCT

On the dyno run with the gas mixer in the Air/Fuel ratio was around 11.5.

After removing the gas mixer, the Air/Fuel ratio dropped around to 11.0.

I am not sure what the optimal AFR is ???

__________________
Wheels: 17" Series 1 XR
Exhaust: VCT with no resonators & 3" mandrel from mufflers back, dump pipe
Pacemaker headers (Waste of money).
Air Intake: T-Series, K&N Filter.
Brakes: Calipers painted red, DBA slotted rotors & Lucas pads.
Windows: Tinted.
Gearstick: Shortened.
Fuel: Dual Fuel.
Dyno: 143 rwKw (Dynodynamics - shootout mode).
Heathcote: 15.87 @ 89.1 Mph.