Porsche Enthusiasts Club Forum

Hi again everyone.

I am gradually getting closer to getting the engine in! Just has some uprated axles fitted to handle the power (along with disc brakes all round to stop the thing) so next on the list is the radiator which is being made and now the fuel system.

So can anyone tell me what the required fuel pressure and flow rate is for the 4.7? Obviously I want something that can easily handle it in case of future modifications.

Will be using a swirl pot with LP pump followed by HP pump with filters before each pump.

Thanks!

Hi

Ok...for my Nitrous system I have to have a fuel pressure transducer on the end of the right hand side fuel rail which sends a signal of the pressure to my Maxx Digital controller , so I can give you some figures of what my S2 "USUALLY" uses... with a standard pump.

Idle = 39 psi
Accelerating = 42 -44 psi
Hard acceleration = 46-47 psi

Under Nitrous power (I have another 16 Venom Injectors for my Nitrous,) which wont affect your pressures = 49-52 psi... but thats running the 8 normal injectors plus my other 16, all from the same pump....

So basically you need a pump which will run between 39 and 47/48 ish...

Hope this helps

All the best Brett

Thanks mate! Looks like the usual infection pumps will handle that easily and a 2 bar adj reg will work well. I plan to fit a temp cheap reg to work with my current engines car then upgrade when the v8 is in. Will have a total of three fuel pumps (two feed from each side of the tank into the swirl pot plus another for the engine)

You know if I will have any probs running a 100psi pump through a reg at only a couple of psi? I know it will be returning a tonne of fuel back to the tank but hoping not to have probs as I don't want to have to buy a temp fuel pump as the cost of fuel system is already about £700 with all the lines, pumps, fittings, reg and swirl pot!

Hi

I am not really sure about the answer to your question as my engine doesnt run fuel the way you will....

All I can say for definite is that you WILL need a pressure of 39 to 48 psi AT THE FUEL RAILS, then obviously a return to the tank (wherever that is lol)

I would love to see some pictures of how you are doing all this when its all fitted

If you ever run it anywhere in the South near me, I would also like to come and see it and watch it run... ?

All the best Brett