xlint89

I'm upping the performance of my 502 NA carb engine and it was recommended that I increase the fuel supply hose to 1/2" and get a better fuel pump.

I see all pick up tubes seem to be 3/8" and most have an aluminum fitting.

What are you guys using to increase the size of the supply hose?

And is aluminum good for this? I thought a brass anti-siphon valve was recommended after a certain amount of HP.

Thanks for any insight into this

F-2 Speedy

whats the hp going to be ?........I dont think a 3/8 line would have any problem supporting 600 +........providing its plumbed correctly

Rookie

A good fuel pump and 3/8" (-6) hose will support 600+ HP.
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xlint89

Going to be near the 600 HP mark. QFT 850 CFM carb

Might be cheap insurance? How do you find out when you need more fuel?

Is there a down side to 1/2" fuel supply lines?

Rookie

No downside to using 1/2" just cost and time. I ran 600 on my Scarab for years with no issues using -6. My fuel pressure maintained at WOT. You'll see a loss in pressure,but that can be the pump or the fuel line. Friend just went from -6 to -8 on his 700HP 540's last year and saw no change. This was on a FAST EFI system. FAST supplied the -6 (3/8") hose with their 1200 HP EFI kit. I know EFI is a little different, but not 500 HP different.

TomZ

You’ll he fine with 3/8. One thing… if you change the check valve fitting, make sure the new fitting doesn’t interrupt flow out of the tank. I removed them on mine and noticed the new fitting going deeper into the tank fitting than it should have. I’m going to put it back the way it was and monitor fuel pressure.

Xcomunic8d

I’m running -8 into my high pressure fuel pump (aem 50-1005) on my LS and -6 from the pump to injectors.

here’s a good video on determining fuel consumption needs of an engine.

I’m considering replacing my pickups right now. A few options I’m considering:

https://www.summitracing.com/parts/tnk-pt-16-12npt

https://www.summitracing.com/parts/jzp-835-008-11

https://www.summitracing.com/parts/fra-900701?rrec=true

ive got a bad case of whileitsapartitis… which has lead to acute complicating conditions of questionablespenditis and irritablewifesyndrome. You’ve been warned.

smokediver

You can buy 1\2 tubing and cut it to fit. As others have said , it’s not necessary. I have a gauge before the carb and a sending unit on my return regulator that’s hooked up to a dash gauge. Also highly recommend the O2 sensor !

xlint89

Thanks for the replies guys.

Hey X, I bought that Tanks Inc 1/2" pick up tube you posted in the first Summit Racing link. I find it questionable. The nylon tube is 1/2" ID, but the barbed fitting that it slides over is 3/8" ID at best. The hole drilled into the 90" looks smaller than that. (the whole thing is a single piece comprising of a aluminum 90* fitting with the hose barb extending out the bottom for the nylon tube to slide over) If I were to use it, at the very least I would have to run a drill bit through it to open up to 3/8" to match the hose barb ID.

F-2 Speedy

There's 1 review on that pickup you bought

★★★★★ ★★★★★ 2 out of 5 stars.

Beware of thread lube used

This fitting is aluminum, and very soft. Thread sealant was not enough of a lubricant to prevent galling and a 1/2NPT to 8AN fitting seized inside of this tube destroyed the threads. The thread form is quickly cut, and not very accurate.

TANKS INC: Please rethink the AL alloy you're using, or better yet make this out of SS like the marine industry does. The only reason I bought this was the 90 deg fitting. I would pay a premium to get this in a material that wasn't so soft and didn't friction weld itself to aluminum fittings.