ok guys now im super confused i have a 91 camaro rs and i went to hook up my fuel lines to my holley carb and the lines are 2 different sizes ? does any one know what those sizes are?

ok well ive been really searching hard and i found out that one is a feed line and one is a return line. now i just need to know the sizes of the lines.... still searching, open to any help thank you.

fuel line 3/8 and return is 5/16 it says it on them on the black soft part

I hope you know that you cannot simply "hook up" either of these lines to your carb!

You MUST get a RETURN-STYLE fuel pressure regulator and put it between the lines and the carb! There is no other way. And ONLY a return-style regulator will work - if you see ANY regulator that sells for less than $80, it is NOT return-style and will not work.

You are looking for the Mallory 4309 regulator, or equivalent.

Your in-tank fuel pump on your 1991 car produces WAY too much pressure for a carb, and since the car has a return style fuel system, you have to use a return style regulator.

thanks could that also be the reason why my motor isint starting ?

There could be any number of things.

Did you change over to an HEI vacuum advanced distributor?
Get the firing order correct?
Check the plug wires for continuity?
What's timing set at?
Is this a motor swap, or just changing over to carb?
What motor do we have? What size carb?

Before we get it started and drive all over the neighborhood and fry the tranny - is this an automatic? If it is ...

Did you install the proper geometry corrector for the TV cable?
Did you adjust the TV cable properly?

Need lots more information...

yea i forgot to mention that i figured he had that part figured out.