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An engine will only draw in as much air/ fuel as it can unless it uses forced induction, whether it swirls or flows straight dont make squat of a difference and all the bends and interferences in the intake sytem will stop any swirling effect anyway. They are only good for scrap or possibly egg rings for the bbq.
I have tried one on a 3.9 V8, with no discernable difference to economy or performance.I also tried it in two places,just before the throttle butterfly and half way along the tube between the MAF and butterfly.
I drove to Brisbane with it and back to Sydney without. Fuel economy was basically the same , and no difference to power.
I chucked mine away when I moved house.
However the theory is OK if the swirl is near the ports. The new Mercedes V6 petrol has retractable aerofoils in the inlet manifold near the ports which extend at low revs to give turbulence in the manifold.
I reckon if you had 8 little hiclones one in each trumpet, it could make a difference, but maybe not. And it would cut high rev performance.
Maybe on a diesel, if it sat just before the ports, it could help. There have been several dyno tests of diesels ( Japanese) in 4WD drive magazines that say an increase in power was seen.
regards Philip A
As I said, it is the concept of a swirl which creates extra flow.Quote:
Originally Posted by isuzurover
Just like swirling a bottle of water to empty it.
But as has been stated, there are bends/restrictions and the end result is squat.
I think we all agree
THEY DON'T WORK
You swirl the bottle to reduce the vacuum forming inside the sealed container.Quote:
Originally Posted by Ralf_the_RR
And intake is totally different...
And laws is laws.... Ya can only stuff so much air through X-dia pipework at Y-psi.... Swirling it wont do squat!
You want better economy on a 3.9l V8... Retrofit the tri-plenum D2 manifold, the longer runners increase torque and assist economy.
I have a 99 LS Disco 3.9 Auto, and can't get better than 16l/100 on the highway, and I would not work it out around town, cause if I did I wouldnt drive it.
I have retrofitted a Thor on my 3.9 and I really agree onthe more torque. with the Unichip and heads I have over 50% more "Tractive Effort" from idle up to 2000RPM or so.
But my economy has not improved.
Next project is to look at the A/F ratios by sticking an oxy sensor in the exhaust, and if possible have the Unichip tuned on road for economy.
If not possible I guess it may be Megasquirt!!! Did I say that?
My economy is about 13.5-14.5 at 110Kmh and 20-22 around Avoca, Terrigal which is pretty hilly.
Regards Philip A
driven nice my old 3.9 v8 disco used to hang around 14l/100 city and down to 11/12l 100 on the highway.
but I detuned here somewhat, and like to drive around at 90ish on the highway.
Blk Knight, tell me more what did you do to get that economy,was it an auto or manual. If I drive at 90 or 110 it doesnt seem to make a big difference.
I Drive from Charters Towers to Townsville once a week, a flat road, and can not get better than 16l/100 , no matter whether premium or standard, it does idle better on premium.
74000k, and I think it is in good knick. Any hints ?
regards Andrew
Draft a semi:D
5 speed Manual, never pegged the pedal more than a thrid, second gear take offs, short shifts, had it detuned with a replacement chip that dropped fuel injection levels by 1/3 unless the throttle was wide open which then switched back to the full fuel map till the brake lights were on..(sort of like 2 fuel maps in one, one for power one for economy and it could tell what I wanted)Quote:
Originally Posted by Andrew
fitted a vacume gauge where I could see it easy and kept it as far right as possable.
disabled the aircon.
fitted electic fans on a dual battery circut
ran my 7.50x16 Lt olympic steel treks at 36 psi front and 48 rear and fitted a 2 inch lift with softer springs to make up for the stiffer rubber
replaced the aircleaner with one twice the size and routed the intake for cooler air
meticulous servicing, advanced the dizzy 1 degree from standard on the vacume side of business. coolant flush and change every second service (I had access to free coolants then)
while driving for economy cog swapped plenty to keep the engine between high idle and about 2800rpm max.
Never actually stopped, made full use of the height of the vehicle to read the traffic up to 5 sets of lights in front If i had to slow down it was always on the box not the brakes (bought it second hand sold it about 4 years,110k Km ish later with the same pads in it still with meat on em).
Drove in the morning evenings or night times only.
You know all those things that come in the book with the hiclone that says " to reap full benifit of this device you should also modify your driving style thusly"
Be warned to drive it that effeciently you need to be really really patient, no road rage, shut it down if its only going to idle for the aircon (which should be off anyway), Connie (swmbo) hated doing the trips where I was scrounging the tank sure Id have enough fuel to make it on city cycle economy with 20l to spare (in jerries) but what if the servo in the middle of nowhere is out of fuel or I hole the tank?.
and it doesnt take much to screw up the economy either.. When I was into her I could empty the 95l tank in less than 400k's