kris

will one 4mm hole do the same job as two 2mm holes to get more air in on idle?keeps cutting out at junctions. ps its a 2.1 zetec turbo on OFAB management.

cheers kris

Al Bags

If you must do it! ...

1 x 4mm hole = 12.6mm area
2 x 2mm holes = 6.3mm area

Those areas are pretty big ... I'd start with 1mm max, near an edge. You can block off again OK if too large.

Keith B

Doesnt sound like a good thing to do but as Al Bags says start with a very small hole and then increase in size. You can always go larger but you can't go back. Doesnt the Zetec have a idle valve? The S2/S1 has a nice manual idle control on one side that you can quickly adjust.

pee vee

id start off by replaceing the idle control valve mate.
they are renound for going on zetecs anyway.
so its almost certainly that.

Oranoco

I would be inclind to find out what teh problem is properly than trying a bodge. Mate used OFAB FRST management on his 2.1 Zetec turbo with no probs so something must be wrong to cause the symptoms you describe

Al Bags

My thought entirely ... However, as I said .. If you must ... !

I have done quite a lot of LPG work, and done this tweak a few times. Mainly on Mechanical injection engines.
Use the bypass is the best way tho.