adjusting A/F ratios on a RB20DET?

[sLo-32]

Ive been told that on the RB20DET there is a screw just behind the injectors facing towards the firewall that adjusts your A/F? Can someone confirm this? and give description of where exactly it is. I know it isnt wise to adjust your A/F ratios without getting it tuned on the dyno, but this is purely just out of curiosity.

[Chris32]

I think from memory, in a manual on the net it has something to do with the idle adjustment or something like that

[Roy]

Havent heard that before, perhaps they meant the idle control valve. I know some of the older Nissan AFMs had an adjustment screw on them, but no way you can confuse the two locations

[blind_elk]

Ive been told that on the RB20DET there is a screw just behind the injectors facing towards the firewall that adjusts your A/F? Can someone confirm this? and give description of where exactly it is. I know it isnt wise to adjust your A/F ratios without getting it tuned on the dyno, but this is purely just out of curiosity.

Who on earth fed you that piece of crap information. The adjustment is for the Idle Air correction, has nothing to do with overall A/F ratios. Its the unit attached to the rear of the inlet manifold. If you look across the engine bay from the driver's side, there is a screw basically inline with the brake master cylinder reservoir.

As Roy said, some of the AFMs had an adjustment for AFR.

[Chris32]

There is a adjsutment on the back of the computer as well, here is the page from the RB20 manual......

It is to do with the idle adjustment, and like the one on the manifold, it will not adjsut anything more than the idle

You can adjust overall AFR's by installing a bleed valve on one of the vacum lines going to your fuel pressure reg. I have seen a article in a old Zoom mag where this was done. From memory -Joel- had one intstalled on his car with decent results

chris