fuel line and fuel pressure
#1
Member
CRAFTSMAN
Thread Starter
Join Date: Sep 2007
Location: Pensacola,Fl.
Posts: 51
fuel line and fuel pressure
i've got 1/2 fuel line all the way to carb.I've got a BG220HR pump with a return line on it.Im running a quickfuel regulator set at 6.5 psi.I've go two line's ran to the carb from regulator with a pressure guage in each and the pressure bleeds off about 3 psi at idle.question is do i need a return line and why is pressure dropping off?I've also got a BG 2 port regulator i can put on it.any help is very welcome!!!never had this problem before.....HELP!!!!!
#2
Senior Member
RACING JUNKIE
Join Date: Mar 2006
Location: EUGENE,OR.
Posts: 3,391
Oh Boy, the return or no return...
It is my experience that most carbs these days can handle more PSI than what needs to be returned. I have done both... but gone back to no return. My issue was giving up the extra fuel via return line & creating a lean intermittent condition at WOT. Scoot
It is my experience that most carbs these days can handle more PSI than what needs to be returned. I have done both... but gone back to no return. My issue was giving up the extra fuel via return line & creating a lean intermittent condition at WOT. Scoot
#3
Senior Member
EXPERT BUILDER
Join Date: Nov 2009
Posts: 267
This is a repost copy from an eBay listing I am watching. I was not aware of this information, but I think I will follow their advice... take it for what it is worth...
"We're still cleaning off our shelves here at Jet Racing and getting rid of some old inventory. You can find some really great deals by looking at all of our listings. Here we have a Barry Grant Throttle Bypass for a Holley Style 4BL Carb.
This is a Linkage controlled bypass with plate mounts under carburetor. Positive response from valve returns unneeded fuel to cell. Use with block mounted 15 psi Six Valve fuel pumps for alcohol.
Do not use with a belt-driven pump. Throttle bypasses were designed to operate with block-mounted pumps and, similarly, diaphragm bypasses with belt-driven pumps. Never use a throttle bypass with a belt-driven pump - they must function in pairs and are not to be mismatched. This is a common mistake and one that will definitely cost you.
You can browse our entire inventory at www.jetracinginc.com - the home of 6 IMCA Modified National Championships! Get your championship car from the best!"
"We're still cleaning off our shelves here at Jet Racing and getting rid of some old inventory. You can find some really great deals by looking at all of our listings. Here we have a Barry Grant Throttle Bypass for a Holley Style 4BL Carb.
This is a Linkage controlled bypass with plate mounts under carburetor. Positive response from valve returns unneeded fuel to cell. Use with block mounted 15 psi Six Valve fuel pumps for alcohol.
Do not use with a belt-driven pump. Throttle bypasses were designed to operate with block-mounted pumps and, similarly, diaphragm bypasses with belt-driven pumps. Never use a throttle bypass with a belt-driven pump - they must function in pairs and are not to be mismatched. This is a common mistake and one that will definitely cost you.
You can browse our entire inventory at www.jetracinginc.com - the home of 6 IMCA Modified National Championships! Get your championship car from the best!"
#4
Senior Member
DYNO OPERATOR
Join Date: Aug 2005
Location: Rifle Colorado
Posts: 585
Did you set the pressure with the the engine running? The pressure will drop with any deadhead type regulator when it's actually flowing fuel, so pressure must be set with engine running.....just a thought
Johnny
Johnny