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914World.com _ 914World Garage _ How much fuel pressure do you run?

Posted by: nebreitling Nov 21 2003, 04:47 PM

Hi all

i'm just wondering how much fuel pressure everyone runs in their F/I 914's (Djet). are there benefits from increasing the fuel pressure from the stock value?

nathan

Posted by: Brad Roberts Nov 21 2003, 04:54 PM

It will run rich if you increase the pressure. Leave it between 29-30.

B

Posted by: nebreitling Nov 21 2003, 05:12 PM

cool, thanks

i just bought an in-line fuel pressure gauge that i'll keep in the engine bay.

full tune up and crane xr700 install this weekend.

thanks again, nice avatar

nathan

Posted by: Brad Roberts Nov 21 2003, 05:30 PM

Um.. you dont need a inline guage. You have a "test port" on one of the fuel rails. I dont recommened leaving a fuel gauge in the engine compartment unless it is liquid filled and hard mounted to something.

b

Posted by: nebreitling Nov 21 2003, 08:16 PM

i don't understand the "test port" on the fuel rail

this is what i ordered:

http://store.summitracing.com/productdetail.asp?p=1668

and

http://store.summitracing.com/partdetail.asp?part=SUM%2D800260

it is liquid filled/mechanical, i was going to splice it into the fuel line near the fuel pressure regulator

my fuel rail looks like this (attached)

thanks, brad. i appreciate (and obviously respect) your advice...

nathan

Attached image(s)

Posted by: Brad Roberts Nov 21 2003, 08:26 PM

One side of your fuel rail has a extra nipple hanging off of it for the cold start injector (that you will never use).

B

Posted by: Brad Roberts Nov 21 2003, 08:28 PM

You ordered the correct pieces (good job).. but the inline piece wont work with your METRIC fuel line. If you force it.. you stand a chance of splitting the ends that you push onto this.. this is of course assuming you have the proper fuel lines on the car.

B

Posted by: nebreitling Nov 21 2003, 08:40 PM

i see.... incidentally, i must have two of the same-sided fuel rail -- as i don't have an extra nipple. on my car, i mean.

errr, on my self too. although once, i was with this chick (true story), and let's just say that there was a mole which appeared to be....

thanks

Posted by: Brad Roberts Nov 21 2003, 08:41 PM

No cold start valve fuel connection ??

B

Posted by: nebreitling Nov 21 2003, 09:35 PM

HA

i'm a damn idiot.... of course there's a third nipple on the driver's side fuel rail! i've seen the thing hundreds of times -- hell, i just replaced the fuel lines a couple months ago. sorry, i'm not quite as incompetent as i might at first appear (almost, though)

hey, that makes me think: i could pretty easily weld a 1/8" NPR fitting onto this 3rd nipple (everytime i say that i get freaked out and remember that mole) and very cleanly mount the gauge to that....

not like this car has ever had a cold start in its life

n

Posted by: Brad Roberts Nov 21 2003, 09:39 PM

By a second pipe setup from somebody and wash it thoroughly before welding.

That way if you screw it up.. you can leave the current one in place.

I like the idea of welding a fitting to it.

B

Posted by: fiid Nov 22 2003, 06:19 AM

Just to be a word of caution - you aren't supposed to weld fuel tanks because the fuel soaks intp the metal.... I don't know if something similar would happen with a fuel delivery tube, or how dramatic the effect would be, but take care.

Posted by: nebreitling Nov 22 2003, 11:30 AM

thanks for the warning, fiid

i did something like this once before on my old morris minor (not the tank) -- i think just the fuel rail piece would be okay as long as it got a thorough wash, dry, wash, dry, and then a test pass with a torch.

i have a friend (mentor, really) who used to weld fuel tanks. crazy motherf-cker. he would top off the tank COMPLETELY and then weld. the theory was that no O2, no explosion. can't believe he's still around.

of course, gas tanks need to be steam cleaned before welding. or better yet, taken to a professional

Posted by: Steve Thacker Nov 24 2003, 03:02 PM

That welding full tank trick doesn't work 100%. I once was welding with an arc under my moms old grabber to fix the muffler. I laid the rod down to reposition my angle. When I scooted around, my arm caught the wand and flipped the rod onto the bottom of the tank. The next thing I know I see these purty flashing lights. The tank went up and blew ole Stevie about 40 ft away. The great thing was I still had my eyebrows! The car needless to say went to a better place....instantly. The lady in the ambulance was real religious and thought the Lord was looking out for me! Uh huh lady why you don't go and tell my mom that and just maybe she won't beat the living hell out of me!!! LOL

I'm also suprised that they didn't pick your friend's / mentor's ass up in Dayton,..err a piece of him for speeding.

Posted by: nebreitling Nov 24 2003, 03:35 PM

HA!

you're a lucky sob too, my friend...

Posted by: Steve Thacker Nov 24 2003, 03:43 PM

Man don't you know it!

I still got my ass beat off once my mother realized that I was OK....Figures LOL

And for my next trick ladies and germs I will perform my death defying welding trick. Please hide the eyes of your little ones. Based upon the last test this could get messy LOL