Dual Weber IDF 40s, Carb Rookie question... Options

[malcolm2]

Hello everyone. I will preface by saying that this is an engine from a 914. (IMG:style_emoticons/default/piratenanner.gif)

But it is in my VW Bus. Just now getting it moving down the road. Everything is new.

Carbs are new and I am a carb rookie, as well. Bought them from Aircooled.net and had them cleaned and set-up for the bus. My 914 has L-Jet FI, this group has taught me enough about that system to be dangerous.

So here is my question for the carb experts. What should the Pump Valve spray look like? It seems erratic and drippy. It kicks in 1st as I open the throttle, not a spray but pore, really. I will say that I see that in all 4.

[930cabman]

I run 12+mm on my 40IDF Weber floats. I prefer to have the fuel level a bit lower as opposed to higher. Is your fuel pressure in the 1 - 3 psi range? I run around 1.5 and seems to work just fine.

[malcolm2]

I run 12+mm on my 40IDF Weber floats. I prefer to have the fuel level a bit lower as opposed to higher. Is your fuel pressure in the 1 - 3 psi range? I run around 1.5 and seems to work just fine.

That is my next recommendation.... As I started doing test drives around the hood, it was suggested to run at 3.5 psi.

Recently, it was recommended to drop to 2.5, so once I get the carbs back on and the idle adjusted and sync'd, I will drop the pressure.

Whole thing started when I noticed the pressure was 1.5 not sure what happened with that, but since then, I have made enough changes to pretty much start from scratch.

So here I go...

[930cabman]

I run 12+mm on my 40IDF Weber floats. I prefer to have the fuel level a bit lower as opposed to higher. Is your fuel pressure in the 1 - 3 psi range? I run around 1.5 and seems to work just fine.

That is my next recommendation.... As I started doing test drives around the hood, it was suggested to run at 3.5 psi.

Recently, it was recommended to drop to 2.5, so once I get the carbs back on and the idle adjusted and sync'd, I will drop the pressure.

Whole thing started when I noticed the pressure was 1.5 not sure what happened with that, but since then, I have made enough changes to pretty much start from scratch.

So here I go...

For me 1.5 works great (on the street), a track machine might be different and I have never ran the float bowls empty with 1.5 psi. Staying on the low side makes sense for me.

[porschetub]

I run 12+mm on my 40IDF Weber floats. I prefer to have the fuel level a bit lower as opposed to higher. Is your fuel pressure in the 1 - 3 psi range? I run around 1.5 and seems to work just fine.

That is my next recommendation.... As I started doing test drives around the hood, it was suggested to run at 3.5 psi.

Recently, it was recommended to drop to 2.5, so once I get the carbs back on and the idle adjusted and sync'd, I will drop the pressure.

Whole thing started when I noticed the pressure was 1.5 not sure what happened with that, but since then, I have made enough changes to pretty much start from scratch.

So here I go...

Not really sure about that ,1.5psi is very low,specs are around are 2.5-3.0 normally for your carbs.
Are you running a quality fuel specific gauge rated to just above your pump output ? ,I have found if you run a say a 10 or 15 psi gauge for a max fuel pressure of 3.5 psi the gauge may be off due to the range of the gauge.
I suggest you check your gauge,cheers.


For me 1.5 works great (on the street), a track machine might be different and I have never ran the float bowls empty with 1.5 psi. Staying on the low side makes sense for me.