debacle-racing

gday all,
does anybody know if you can run a return line back to the tank from the pump?
or do you have to put a t piece in line after the pump but before the reg?

cheers, justin.

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ch7472

The best thing to do is to run a return line from the reg. You wil find the mallory 3 port retun reg the best for this. Run your fuel line up to the reg out to the carby and then back to the tank. Why are you useing a holley black.

debacle-racing

because i own it.
whats wrong with the black pump anyway. it is on a race car. i got the black because a few people i had spoken to said that their blue pumps wernt cutting the mustard. i know there is probably a million cars with blue pumps that run fine. im not knocking them (getting in early before i hurt someones feelings) the black pump is there now and its staying there. i have blown enough money on this car.
i also run a bg 2 port reg.
i didnt really want to run a return line from the carb back to the tank. its a pain in the arse.
any other ideas?
can you run a return line from the pressure relief valve in the pump?

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TruBlu351

If you ran a t-piece at the pump outlet there would be hardly any restriction flowing back to the tank.....you would therefore have almost zero pressure at the engine bay reg. These holley carbs (mallory too) weren't designed to run a return line at the pump.....unlike certain Barry Grant models that have a built in pump bypass.

So, as far as I can see it, you're going to have to swap out your standard single line regulator for a bypass reg and plumb in a return line to the tank. Normal regs don't allow this.

BUT, any reason why you need the bypass setup in the first place? It's normally a street car thing where it eases the pump load and extends its life....being a "race car" you should be OK with the single line??

Plumbing a return line isn't that hard. I used 1/2" aluminium tube bent to shape wuth tube nuts on the end. Looks schmick and relatively cheap. Here's a pic of my mallory reg and return line out the bottom.

Note, the return line should be less restrictive than the feed line to prevent backpressure....although 1/2" both ways should be fine.

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XE Falcon
393 Tremec TKO 9"

xdclevo

You will have to run the return line back after the reg under the bonnet, or do like most and don't run one at all. The black sounds like a good pump. I am about to buy a new one, but the Mallory 140. Sounds like both do the same job by the specs.

debacle-racing

thanks trublu351,
ive been having a few probs with the fuel system, and this is just a starting point.
the pump has konked out a couple of times (wiring is fine) and i thought that this may be the problem.
cheers, justin.

here is the "race car"
http://www.hioctane.com.au/photos/14...s/DSC_7601.htm

this is before the caltracs.

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TruBlu351

Hey, nice ride! Getting some airtime there on the fronts!!

How do the new 60 foot times compare with teh new caltracs?

Has the pump been audibly stopping or just fuel pressure dropping off? ie: how's your tank pickup setup? You running a dash fuel press gauge?

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XE Falcon
393 Tremec TKO 9"

TruBlu351

Hey, if you put the link inbetween these characters with no spaces, the pic gets displayed.

[img]link[/img]



This one looks crazy.....would be a handful at 120mph Please tell me you whopped him!

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XE Falcon
393 Tremec TKO 9"

debacle-racing

that run broke the diff, slapper bars,bell housing, gearbox, engine mount and it was a 1.53 60ft

we have actually run better ets with the caltracs (dunno why) and the 60 fts are up to shit, to the caltracs defence, we have had them set up wrong, really wrong. i didnt set them up the way i was supposed to and i had the wrong springs in the ute. we just purchased some rancho adjustable shocks but havnt run them yet, but cant wait to! the ute is bare bones at the moment getting a cage and an engine freshen up.

the pump has stopped. the old tap with the screwdriver handle trick fixed it though. fuel pressure seems fine (fuel pressure gage is mounted outside the window) pressure not dropping off at all throughout the run.
i think i have some fuel evap. probs too.
at present i am running 1/2" hydraulic line from the cell to the reg. i am going to change that to 1/2" aluminium line (like in the pic) while the car is in pieces.

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debacle-racing

ithanks for that.
i havnt raced him yet, the ute has run 11.40. i think the van runs similar times and runs a bit of happy gas. wild ride. he reckons its fine to drive.
i will stick to the ute i think!

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