RB20: which cylinder runs leanest?

[JH32]

Does anyone know which cylinder runs the leanest on an RB20?

I've heard some people say cylinder 6, but I can't remember if that is for RB20/RB25/RB26 :confused:

Cheers

[Doctor]

Ive heard 6 too mate.But like yourself cant confirm.

[Skyrine-Dave]

i would just do the same as the RB25 guys and put my highest flowing injector in 6 then the next highest flowing into 5.

[blind_elk]

I think its 6 on the RB26. It's furthest from the main air inlet.

But I think the problem is more related to the fact that #5 & #6 are furthest from the cool cooling water, so the area around #5/6 cylinders and combustion chambers do not get the same degree of cooling that the other forward cylinders get.

[yogi000]

On the VL RB30 it was was cylinder 6, but apparently this wasn't the case on the nissans as "apparently" the angle that the engine block sits was to fix this.

[Roy]

I suspect this isnt an issue on RB20s.

How highly strung is your RB20. Unless you are looking at over400hp i think you should be more worried about oil pump/cooling, and water pump/cooling.

[BHDave]

If you chop up the plenum and front mount the throttle body than you will definately run leaner on 6.

In general the airflow on a factory manifold is pretty even. Unless you are really leaning on the engine it isn't a big issue.

[red17]

Id say 6. I did 2 valves in 6 from detonation, all other cylinders were AOK.

Red17

[JH32]

I still have the factory plenum, and I only have mild upgrades so far. The reason I ask is because I now have an SAFC2, and want to monitor the "leanest" cylinder(s) with the knock sensor.

By the looks of things it's cylinder 6 ... cheers guys