You're right on that one but at the 4L power level I'll have WAY more torque (stock 4L torque is 225 ft lb at the flywheel. Stock 4L HO is 238 ft lb at the flywheel)
The existing Ford pump is capable of producing in excess of 60 PSI, but that is because of the way the fuel system is set up for gas injectors. The pump will only produce pressure when there is restriction. If the fuel is free flowing to the IP and then the return line, the pressure will only be what the volume of flow generates through the restriction of the IP.Exactly. I'm using the stock Ranger pump as my lift pump and will add an aftermarket, adjustable fuel pressure regulator to dial the pressure down to TDI-friendly territories.
I did that on an engine swap (albiet not a VW engine), and the supply pressure of 60psi that I had would go into the injection pump, and any excess went into the return line. But the return line of the injection pump was shared with the injector return line, so the now higher pressure of the return line was making those little slip-on return lines at the injectors pop off. Not good, and diesel all over the engine bay haha!
I'm leery of putting unregulated fuel pressure to the inlet of the IP. For one thing what happens if I pause between turning the ignition on and cranking the engine (ie waiting for GP's)? I'm not too concerned about additional cooling/lubrication since the IP is designed to survive without any additional flow provided by a secondary pump. I would be worried about the functionality of my N108 since it works off the differential pressure between the case pressure and the inlet pressure to the pump. Too much inlet pressure (60+ psi) could force the injection timing piston to be full retard and not allow any advance.
OK. I got it all sorted out.
I purchased the Nitrous Express 15956 regulator which is a modified Holley 12-803 (single inlet, dual outlet, 4.5-9psi operating range) with an added bypass port in the inlet AND a fuel pressure gauge. This small fitting accepts a jet that bleeds off pressure/flow so the pump isn't dead headed into the regulator. Once assembled the fitting and jet are an AN-3 fitting. I wish they had said this somewhere in their wesite! They simply state it is a D-3 outlet which doesn't mean anything to me...maybe this is normal lingo in the nitrous/aftermarket crowds.
For future reference this kit comes with:
I had to purchase:
- Regulator
- Mounting bracket
- Bypass fitting
- Bypass jet
- 1/8NPT - 3/8NPT reducer
- Fuel pressure gauge
Ok, you may now return to Toyota-TDI-awesomeness.
- AN-3 to 1/8NPT 90deg adapter. I would have prefered to go up to a 1/4NPT or higher but 1/8NPT was all I could find for adapters from AN-3. For my install location I also chose to go with the 90deg turn. I put together a few different combinations of adapters and this ended up being the cheapest at $16.
- 1/8NPT - 5/16" barb (not pictured)
- M6x1.00, 12mm long bolts and washer (x2) and tapped the holes to receive them
- 3/8NPT - 3/8" barb adapter (x2). Again, I would have prefered 5/16" barb but was limited by the selection at my FLAPS. I can get a 5/16" line over these barbs so I'm going with it.
You could just not have a fuel pump and simplify the issue al la me? lol
hah, less accurate.. amatureIs there a slightly less accurate version of it on the other end of the motor?
hah, less accurate.. amature
