fuel line questions

All right race guru's fill me in if I'm missing something. I run a -10an from my tank to the pump (about 2' away from the tank) to -8an line up to the reguoator and 2 -8an lines to my carb. This setup was recommended to me by several people I trust (1 is the owner/driver of the Lucas Oil Monster truck), and I've had no real problems with it except for a pump going bad on me. Putting the new motor in this past weekend to try to run, I realize I didn't have the carb fittings for the HP Dommy carb and everywhere was closed on Saturday night for a Sunday race. Anyway talked with a few local guys that run big motors (some chevy, some ford guys) and they ALL asked why was I running -8an from the regulator to the carb. I ended up borrowing some -6an fittings and lines from a guys wrecked truck that has way more hp than me, and was the typical setup that the 5 other people i talked to ran. So am I missing something with them using the smaller lines from the regulator to the carb? The guy I borrowed the lines from runs a -10 from the tank all the way to the regulator and steps way down to the -6 stuff. I would think the severe drop would cause a choke point and not keep enough fuel fed to the bowls. Thoughts, explanations, trashing my buddies, what you got?

most folks think they gotta have a garden hose ran to the carb which has a very small hole in it when you think about it. #8 is a hell of a line IMO.i'v saw some fast stuff with a stock 3/8 line.

I run a -12 to the pump, -10 to the reg, and 2 -8's to the carb. I have had no problems with fuel delivery.

'65 T-BOLT wrote:I run a -12 to the pump, -10 to the reg, and 2 -8's to the carb. I have had no problems with fuel delivery.

what kinda pump you got? a #12 line?g/d,thats a LINE

Big pumps need a big inlet hose..........the BG400 and the Prostar 500 really need a -12 or you can damage the pump from cavitation. -10 to the regulator is fine, from there -6 is fine for gas and maybe better.............take a look at some prostock motors and see what size they use...........something about turbulance into the needle and seat. Alky you better have -8's to the carb.

Bg400 with an aeromotive -12 filter ahead of the pump, bought the bg pump for cheap, want to swich to a aeomotive or magnafuel pump in the future. I know it is all over kill

alky ...-8 to the carb! cool! now all i need to do is have Jon come to MD and set me up!

he'll give you the A+tune

that he will! I hear that the tuning window is of a larger margin with alky. is this correct?

So long story short, going back to the -6 line from the reg to the carb wouldn't be a bad idea then? My pressure is set at around 7 1/2 psi and on the throttle, I've seen it go down to about 5 1/2-6 psi and that was on the old motor and 850dp carb. I don't want to starve the new motor and 1150 dommy!

i dont think the line will starve it as long as the pump's a pumpen.

for your little bitty engine Id figure 5/16" hard line and a stock mechanical pump would work.