Bon, j'ai mis une heure et demi avant de retrouver, j'ai failli craquer...
Pourrais tu penser très fort "je t'aiiiiiimeeeeee!" ?
Ca me va, moi aussi
Le lien:http://forums.tdiclub.com/showthread.php?t=369604
Le texte proprement dit, en espérant que celà te serve:
The trick on these pumps is 2 fold. as it is a staged pump!
1)inertia is the killer of the 12mm and 14mm. 2) the factory limited the front rotary vane pump. It can only flow a fixed volume of fuel. No matter how much piston and cam plate mods you do it is a fundamental limit.
4mm cam plates do exist! They are not cheap, ~400ea. From the research I have done the 11mm pump is 3.3mm and the 10mm is ~3.1mm.
Using that
a stock 10mm pump flows .243cc/rev
a stock 11mm pump flows .314cc/rev
a 12mm/10mm combo flows .351cc/rev
a 12mm/11mm combo flows .373cc/rev
a 10mm/4mm camplate flows .314cc/rev
a 11mm/4mm camplate flows .380cc/rev See that you can see a 11mm head with a 4mm cam plate can actually out flow the more aggressive 12mm/11mm combo. Now the other advantage of this combo is the weight of the plunger!
The 12mm plunger is heavy and the bigger the mass the more issue, plus it has more surface area which is more friction!
More friction is more heat, which can only be cooled with fuel. The issue that keeps coming up is the piston starving of fuel! This will not change with any piston or camplate. The higher the RPM the more fuel demand the more the primary issue becomes apparent.
The thing that will always limit the pump is the supply pump. It's a fixed rate vane pump, lift pumps help, but you can't really shove much more fuel in there. I've been playing with 6bt parts to see if I can find something that drops in and will supply more fuel. This would mean more fuel flowing through the entire pump, meaning cooler fuel, and less high RPM starvation!
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