I've got a 2ltr zetec on twin weber 45 carbs, it runs fine at idle, starts fine, however if u blip the throttle hard the carbs seem to bog down almost to the point the car cuts out, however if u rev it with light throttle it revs up fine, no problem atall, just under hard throttle it bogs and almost dies, any ideas? Thanks.

 

Either wrong jets for car/setup or not setup/balanced right, did you just bolt them on and plum them in or have you set them up

 

I bought the carbs brand new and they were setup and jetted for a 2 litre zetec, bolted them on there and it ran fine, just when u give it the hard throttle it bogs down and almost dies, I haven't had them balanced since they have been on the car so possibly could be a balancing issue.

 

Yeh check the ballencing, also what pump/fuel setup is it using, the whole bogging out issue as you probily know is sucking in to much air at an instance, which you can't help but you can aid it by giving it more fuel when required

 

I'm using a facet low pressure pump rated from 2 - 5 psi, and I'm using an adjustable pressure regulator set at 2.5 psi, I can't see or hear any air leaks anywhere, just have to get them properly balanced and see how it gets on, they are the later dcoe carbs with the 5 progression holes to eliminate the dreaded flat spot on the zetec's.

 

The flow rate may not be able to keep up with the throttle response

 

Do I need to adjust the fuel pressure abit then? The regulator dial goes from 1 - 5 psi, I was told 2.5 psi is enough but I'm not 100% sure?

 

You should have an ignition on fuel pressure, a pressure at idle and it should be altered to suit up through the rev range

 

You have to decide if this is bogging down through over fuel or stumbling from being lean.