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[Matias]

My fuel pump, hasn´t been working so well, the last day´s. So I was thinking of replace both of them, (The in-tank and the other) with one mallory or holley fuel pump with a regulator. I know that I won´t have any increase in performance with these, but I plan to make some improvement´s in the future, like a boost control, an MSD, may be an intercooler, so I believe that a bigger fuel pump with a pressure regulator will make thing´s easier.
Now, Does anybody know wich is the fuel pressure that I need for a stock 1981 931?. Do you think, that changing the stock fuel lines with aeroquip bigger lines and fitting´s will benefit in someway?
Thank´s

[924RACR]

Sorry dude, that's not an option. Those are mostly for carburetted cars, top out at maybe 1 bar/15psi. The CIS runs at a higher pressure than even EFI, at around 70psi, depending on conditions. You'll have to use a pump designed for a CIS system, which means either the original Bosch pump (they suck, and I work for Bosch, you figure it out) or an aftermarket replacement from Pierburg (a subsidiary of Hella), which are much better, quieter, and cheaper. I think you'll have to get an original for the in-tank pump, though. Check it out with your suppliers. Let me know if you need assistance getting a Pierburg pump, I have a supplier up here in Michigan who does ship, and hopefully will ship to Argentina... hope things are going better for you now down there!!

_________________
Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

[Zuffen]

I think Bosch has an all series of pumps rated for fuel pressure and rate that are for the doit yourself guys. They might have a pump in the CIS operating range

_________________
Bob Dodd - 924turbo@cox.net
931 1982, 944 1982 euro, 924S 1988SE, 93 968 tip 06 Silver Cayenne S, 06 Black Cayenne S

I have Way too many cars, parts for the 931,944 and 951

[Matias]

I assume so that getting bigger fuel lines isn´t an option either. Do you think, would be a problem if I replace the stock lines and banjo fitting´s with same diameter braided hose´s and aerquip fitting´s?

[924RACR]

I don't really understand why you'd want to replace the fuel line with anything other than stock. I know from personal experience that the Aeroquip stuff is highly expensive, and there's no performance advantage here associated with it's use.

_________________
Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

[Matias]

That´s because here in Argentina, due to the new economic law´s is impossible to acquire something imported. So I ask if the aeroquip style, hose´s and fitting´s will work right, because, we have a local manufacturer of those kind of thing´s. For me is much more cheapper than buying porsche-bosch part´s.
By the way, has anyone try to replace the oil hases that goe´s to the turbo and oil cooler with aftermarket´s one´s. Those hose´s are really expensive.....

[numbers]

Matias, I replaced the return hose from the turbo to the oil pan with standard 3/4 inch heater hose and hose clamps using the fittings off of the original hose. It works fine. Just take the original hose, and cut it off just short of the ends of the fittings. Then place one of the fittings in a vice, and cut the crimped piece off of the fitting and the remaining stub of hose using a hacksaw and cutting lengthwise on the fitting. Be careful not to cut into the internal barbed part of the fitting. The crimped part will peel off after you cut through it on one side. Do the other fitting the same way, and put your new length of hose onto the barbs on the fittings, and secure with standard stainless hose clamps. Total cost is a couple of bucks. I still have my original lines going to the cooler, so I don't know if this same method will work with them. However, it will probably work, except you would need to use a higher pressure rated hose than the heater hose. Heater hose works for the oil return line because it is not under pressure. But, of course, the cooler lines have presurized oil flowing through them.

[Matias]

That´s a great idea number´s... is ridiculous the cost of those original hose´s.