fuel line

marvstrick · 02-04-2010, 08:42 PM

i have a 502- 450 hp chevy. iam running#8 fuel line from regulator,my question is would #6 be better. c/cm 9777 marvin

njk53 · 02-04-2010, 08:48 PM

Do you mean from the regulator to the carburetor?

marvstrick · 02-04-2010, 08:52 PM

yes from regulator.

Mark Lewis · 02-05-2010, 08:46 AM

Had a 750 from davinci that always ran better than a 850

tj310 · 02-05-2010, 09:11 AM

If your reg is in front of carb bigger is better. Thanx Trevor

Greg Reimer 7376 · 02-05-2010, 08:53 PM

This sounds crazy, but running a big huge line from the pump at the rear of the car to the regulator at the front can aggravate a fuel starvation problem.You can sit there with the pump on adjusting the regulated fuel pressure all you want, and to no avail, because the weight of the fuel in the large line reacts to inertia forces within itself, resisting forward motion inside the line ahead of the pump. A smaller main fuel line doesn't do this,because inertia forces on the fuel are much less. Sometimes,more isn't better. Number 6 AN fuel line is about 3/8" inch ID, the #8 should do it, but that's where the placement of the regulator in front of or to the rear of the carb might come into play here, as well.Pro stock cars leave so hard that it takes a huge push to overcome the weight of the fuel trying to stand still in the line.High pressure overcomes the inertia on acceleration, but floods the engine by overcoming the needles and seats when the car isn't accelerating.Critical balance here between fuel flow requirements of the engine,fuel line diameter,pump volumne,and pump pressure.

Ken Haase · 02-06-2010, 01:48 AM

Aren't the fuel cells up front on Pro Stocks now?

Greg Reimer 7376 · 02-06-2010, 11:24 AM

If they are, that's why!!

02-04-2010, 08:42 PM	#1
marvstrick Member Join Date: Jan 2008 Posts: 149 Likes: 143 Liked 32 Times in 9 Posts	fuel line i have a 502- 450 hp chevy. iam running#8 fuel line from regulator,my question is would #6 be better. c/cm 9777 marvin

02-04-2010, 08:48 PM	#2
njk53 Senior Member Join Date: Jul 2007 Location: East China, MI Posts: 504 Likes: 0 Liked 0 Times in 0 Posts	Re: fuel line Do you mean from the regulator to the carburetor? __________________ Nelson Kowal Stock 345

02-04-2010, 08:52 PM	#3
marvstrick Member Join Date: Jan 2008 Posts: 149 Likes: 143 Liked 32 Times in 9 Posts	Re: fuel line yes from regulator.

02-05-2010, 08:46 AM	#4
Mark Lewis Member Join Date: Apr 2006 Posts: 330 Likes: 55 Liked 184 Times in 37 Posts	Re: fuel line Had a 750 from davinci that always ran better than a 850

02-05-2010, 09:11 AM	#5
tj310 Member Join Date: Sep 2009 Location: Dresden On. Canada Posts: 460 Likes: 0 Liked 0 Times in 0 Posts	Re: fuel line If your reg is in front of carb bigger is better. Thanx Trevor

02-05-2010, 08:53 PM	#6
Greg Reimer 7376 VIP Member Join Date: Nov 2008 Location: Glendora,Calif. Posts: 1,112 Likes: 165 Liked 654 Times in 209 Posts	Re: fuel line This sounds crazy, but running a big huge line from the pump at the rear of the car to the regulator at the front can aggravate a fuel starvation problem.You can sit there with the pump on adjusting the regulated fuel pressure all you want, and to no avail, because the weight of the fuel in the large line reacts to inertia forces within itself, resisting forward motion inside the line ahead of the pump. A smaller main fuel line doesn't do this,because inertia forces on the fuel are much less. Sometimes,more isn't better. Number 6 AN fuel line is about 3/8" inch ID, the #8 should do it, but that's where the placement of the regulator in front of or to the rear of the carb might come into play here, as well.Pro stock cars leave so hard that it takes a huge push to overcome the weight of the fuel trying to stand still in the line.High pressure overcomes the inertia on acceleration, but floods the engine by overcoming the needles and seats when the car isn't accelerating.Critical balance here between fuel flow requirements of the engine,fuel line diameter,pump volumne,and pump pressure.

02-06-2010, 01:48 AM	#7
Ken Haase Member Join Date: Mar 2007 Posts: 233 Likes: 0 Liked 1 Time in 1 Post	Re: fuel line Aren't the fuel cells up front on Pro Stocks now?

02-06-2010, 11:24 AM	#8
Greg Reimer 7376 VIP Member Join Date: Nov 2008 Location: Glendora,Calif. Posts: 1,112 Likes: 165 Liked 654 Times in 209 Posts	Re: fuel line If they are, that's why!!