88BlueGT

Well, I know that its a return style fuel system from the factory so anything not used gets returned to the tank BUT I was just wondering if there were any disadvantages of running one on a stock car. It just makes me wonder why they even sell 155's & 190's if it doesnt harm anything to have the extra fuel flowing. Why not just make one upgrade to a 255? Any comments on this?

88BlueGT

TTT

r.barn

the extra fuel flow will heat up the gas more than it would normally

when you heat gas it loses octane, you will derate the octane in your tank
by heating it up more than is needed by constantly pumping it up to the
engine for no reason.

my 155lph pump feeds my engine just fine.

koesterca1

whoa I didn't know that...it can't be by much though.

OnyxCobra

so what size fuel pump is good for a boosted head/cam 302? say to like 8psi.

r.barn

255's for boost

boosted engines require much more fuel per hp made
than an n/a engine

OnyxCobra

thank you. so if i got the 255 now i'd be okay til i added the blower?

r.barn

sure it just pumps more fuel up to regulator than you need.
excess just gets sent back to tank.
Though it can cause some back pressure against the pump
which will make it run hot, thus heating the fuel even more.

samseed101

You would be surprised. Heated gasoline expands quite a bit. As it expands, you get less "energy" or molecules in the same volume of space. When heated, gasoline expands about 2.5 more than water at that same temperature. So it can make more of a difference than you think.

BTW, that is also a reason whyon hot days, you wantto get gasoline early in the morning while it's cool out.The industry standard says they are supposed to sell it at 60 degrees. But there have been reports that some companies don't do that.If the gasoline is slightly warmer... thenit expands and you actualyl get less gasoline molecules per gallon. Therefore, you end uppaying the same amount of money for a lesser amount of fuel.

2 kwik

2 PUMPS FOR A BOOSTED CAR..I USE A 190 AND A 105