When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I got my new fuel system put together at the engine end today. I wanted to run the feeds to the fuel bowls to each side of the pressure regulator, but with the fittings in place, it was just too tight. I had to run the lines to the opposite side of the regulator. It worked out well though.
The carb is a old 4781 I resurrected from the grave. It had a hack job done to remove the choke tower. I cleaned up the poor machine work and shaped the top like an HP. I also put jets in the air bleeds, idle restrictors and power valve feeds and turned it into a 4 corner idle. Put a new base plate on it too.
I haven't decided where or how I will mount the pump in the rear, or exactly where the feed and return lines will run yet. I'd like to run the lines before I drop the body back on the chassis, but I'm not sure if the -8 and -6 AN lines will fit where the original steel lines were.
. I'd like to run the lines before I drop the body back on the chassis, but I'm not sure if the -8 and -6 AN lines will fit where the original steel lines were.
Mike
They'll fit for the most part. I squeezed a -10 and -8 in the factory line locations.... Its super tight but they go. I couldn't use the oem clamps obviously though... Attachment 48355443
They'll fit for the most part. I squeezed a -10 and -8 in the factory line locations.... Its super tight but they go. I couldn't use the oem clamps obviously though...
Thanks Allen. I have some of the rubber lined clamps like in your photo I'm going to use, but it looks like there might not be room for them over the top of the frame in the fender well area.
Mike
Last edited by v2racing; Nov 21, 2017 at 12:47 PM.
Thanks Allen. I have some of the rubber lined clamps like in your photo I'm going to use, but it looks like there might not be room for them over the top of the frame in the fender well area.
Mike
Right...Can't use clamps in the fender well area, I tried.... I actually just ended up using BIG zip ties (3/8" wide and 18" long) to just go around the whole frame/fuel lines in 2 places in the fenderwell area. Kind of bubba but....it works, its not visible with the tire on and it holds both fuel lines with one tie instead of individual clamps.
I wouldn't mount the lines in a way that you will not be able to replace them with the body is on, because they don't last forever. I wanted mine relatively serviceable.
Also, make sure to cap off the factory return line at the tank. I forgot, and I was getting hellacious fuel smell/vapors in my garage. I swore I had a leak somewhere. Then I remembered I but the return on the rubber hose section at the tank, and never plugged it...Problem solved.
Right...Can't use clamps in the fender well area, I tried.... I actually just ended up using BIG zip ties (3/8" wide and 18" long) to just go around the whole frame/fuel lines in 2 places in the fenderwell area. Kind of bubba but....it works, its not visible with the tire on and it holds both fuel lines with one tie instead of individual clamps.
I wouldn't mount the lines in a way that you will not be able to replace them with the body is on, because they don't last forever. I wanted mine relatively serviceable.
Also, make sure to cap off the factory return line at the tank. I forgot, and I was getting hellacious fuel smell/vapors in my garage. I swore I had a leak somewhere. Then I remembered I but the return on the rubber hose section at the tank, and never plugged it...Problem solved.
I have just a little more room than you with -6 and -8 instead of -8 and -10. I may try the clamps to see how they fit. I have the body lifted with a 2 post hoist, so it's easy to set down and pick back up if I don't like the fit.
To replace down the road, I'll just cut the outer clamp with a cutoff wheel and pull the outer hose out of the way. I can then take the bolt out of the clamp to get the inner hose out. I'll just have to use a zip tie to put it back together then.
By the way, I'm still planning on doing a tech article here on building the 4781 850 double pumper and how all the mods lend to finer tuning. I've just been busy trying to get the frame off back together.
From: Las Vegas - Just stop perpetuating myths please.
Nice work V2! I like that constant return as it will maintain pressure steady all the time (have a return on my Q-jet also).
I estimate you spent more $ on all those fittings and lines than you did on the carb.. But it reads like you have some hours worked into that carb to.
As for electric fuel pumps if you drag race it's best mounted aft of the tank and to minimize noise transfer it needs to be mounted to the frame instead of any body panel - using isolation mounts.
Nice work V2! I like that constant return as it will maintain pressure steady all the time (have a return on my Q-jet also).
I estimate you spent more $ on all those fittings and lines than you did on the carb.. But it reads like you have some hours worked into that carb to.
As for electric fuel pumps if you drag race it's best mounted aft of the tank and to minimize noise transfer it needs to be mounted to the frame instead of any body panel - using isolation mounts.
Congrats.
You're right on the cost of the lines and fittings VS the carb. A friend gave me the carb. It had been setting in a bucket in his garage with a leaking roof. The bucket got water in it and destroyed the base that was on the bottom. You can see where there was corrosion on the top of the front bowl. I didn't spend much building the carb, mostly time.
The Mallory 140 pumps are really quiet, not like the noisy Holley pumps. I haven't decided on the mounting yet. I'll decide that once I put the frame back under the body.
Now that I have the body back on the chassis, I buttoned up the plumbing for the fuel system in the rear. I still need to get a rubber lined clamp to hang the filter with.
From: Las Vegas - Just stop perpetuating myths please.
Okay I had to look over the pictures several times. That's a fancy sump built into your stock tank. That should help considerably. Though you could move the pump further to the rear I don't expect any problems as it would be difficult to uncover the pump inlet line enough to get it to run dry.
Nice work. You may want to verify your gauge calibration and set your pressure with flow in progress.
Nice set up.
Mine is similar but I mounted my pump in front of the tank. No tire in spare carrier. I’m using an Aeromotive pump and regulator. Too many problems and too much noise from the Holley pumps for me.
I wanted to sump mine too but I didn't want to lose the spare tire tub capability...(I need it for traveling)
Looks like you have a solid setup there.
I did some testing with mine last week with a new electric fuel pressure gauge and the fuel pressure never drops below 7 psi at WOT....even at 140 mph...
Nice set up.
Mine is similar but I mounted my pump in front of the tank. No tire in spare carrier. I’m using an Aeromotive pump and regulator. Too many problems and too much noise from the Holley pumps for me.
Yes, the Holley pumps can be troublesome and are way noisey.
I wanted to sump mine too but I didn't want to lose the spare tire tub capability...(I need it for traveling)
Looks like you have a solid setup there.
I did some testing with mine last week with a new electric fuel pressure gauge and the fuel pressure never drops below 7 psi at WOT....even at 140 mph...
Makes you feel good inside...
You definitely have a system that you can grow into. Is there a 550 plus incher in your future?
New fuel system
. But it reads like you have some hours worked into that carb to.
