Fuel inlets for IDA Weber

[sen2two]

For those of you running a down draft Weber. Have you noticed any benefit from running the fuel inlet to the top port instead of the side port?

I am using a Mallory comp 140 fuel pump and Mallory 4309 regulator with all -8 fuel fittings and lines up to the regulator. From the regulator to the Weber is -6. the car is a 51 mm IDA Weber. And I am debating on using the top or the side port to feed the fuel. I see most of therace cars that use Weber's use the top port, but still others use the side port. this card is setup for blow through if that makes any difference.

[Whizbang]

honestly.... i have no idea.

My 48 IDA runs through the side port. I do not see any reason that it would matter and instead its a form of "option" for connection fuel lines on multi carb setups on non rotary applications.

[730RWHP12A]

inlet you choose wont matter. the restriction is the needle valve.. -6 is plenty big

[sen2two]

I have a 3.2 glass ball needle valve from Jaycee.

Ok, The main reason I ask is because all of the Jaycee Webers I have seen use the top inlet as a feed source and the side port is plugged. I also noticed the top port is larger than the side port. But both are larger than the -6 line so I was unsure if that mattered. I was also was unsure if removing some of the turbulance had any effect on the needle valve regulating fuel as well....


I might be over thinking here though. My blow through set up isn't that wild.

[Whizbang]

what pump jets are you running, out of curiosity

[sen2two]

Not sure about my pump jets. I haven't started the car yet (on this tune) since I am building the turbo manifold right now.

37mm chokes
3.2 Glass ball needle valve
60f10 idle jet
120 idle holder
195 main
150 air corrector
f-3 turbo e-tube

[730RWHP12A]

Not sure about my pump jets. I haven't started the car yet (on this tune) since I am building the turbo manifold right now.

37mm chokes
3.2 Glass ball needle valve
60f10 idle jet
120 idle holder
195 main
150 air corrector
f-3 turbo e-tube

your going to need at least a 65 or 70 idle jet, and unless your turbo is tiny a 190 main jet is wayyyy too small.. start rich, not lean. i would drop in some 230 main jets.. what size turbo are you running? you have the black solid float i hope.. where did you get the carb hat?

[Whizbang]

i run a 195 main jet for the 13b 6port stocker. With 165 air
65 idle jet
F7 emulsion tube
65 pump jets
closed exhaust
40mm venturi

[sen2two]

your going to need at least a 65 or 70 idle jet, and unless your turbo is tiny a 190 main jet is wayyyy too small.. start rich, not lean. i would drop in some 230 main jets.. what size turbo are you running? you have the black solid float i hope.. where did you get the carb hat?


The turbo is a Holset HC1. Similar to the hx40 but much smaller hot side and slightly smaller compressor side. I only plan to run 10-12 psi on this set up.

I made my own carb hat. And yes I have the black float already.

[sen2two]

I should ad that this is on a small street ported 12a.

[730RWHP12A]

I should ad that this is on a small street ported 12a.


it should run good, granted the carb hat seals properly..