ok guys im buying a new mechanical pump, 110gph holley brand, and it only has 2 connections. one inlet for fuel from tank, and one from the pump to carb. my quest is what one do i connect to the pump and which one do i cut and make it higher than tank for the venting? is it a vent or a return line?i wanna get it on the ball but i dunno which to do. thanks guys

 

The smaller line is a return, not a vent. It needs to be blocked if you're not using a return-style pump or regulator.

 

ok and wont have any issues blocking it?

 

No

 

k thank u. since im running a bigger pump, do i need to run bigger fuel line? im gna be runnin a 100shot of nitrous to

 

No.

Not sure why you went with that pump. I'm running a Carter M6626 ($29.39 on summitracing.com), rated at 120 gph. It has the return line, uses the stock 3/8" supply and 5/16" return lines.

The reason the factory used a return line was to reduce the tendency for vapor lock.

 

thats awesome do u got the part number? id like to do that way better then blocking thank u man

 

i found the pump and ordered it. thank u. do i need a regulator for this pump?

 

No

 

U BEEN A REALLY BIG HELP!!!!!!!! THANK U. but one last question. y dont i need a regulator? will pump be ok running daily and with nitrous here and there? also it says up to 6.5psi max, dont i need more then that to run nitrous?

 

?

 

Any fuel pumped that exceeds 6 psi to the carb is sent down the return line by the pump.

 

im still confused. then if it only pumps 6.5psi am i gna ruin my motor for not accomidating for the nitrous since u need 7psi or more?

 

It would have been useful to know you were planning on using nitrous earlier.

 

take it i cant use that pump then? thought i posted it but must notta sorry.
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can that pump support 100 shot of nitrous?

 

i wanna go a different route and use an electric pump. can i just tap in by the tank and use that line to go directly to the regulator, and nitrous? totally bypass the mechanical pump and lines?