CMA small detail question (part load)
 

Hi everybody, i searched all over the forum and still haven't found a solution for one detail in the part load measurement.

How can i set the throttle valves to exactly 9 degree angle, so i can get a good measurement? I have a wideband sensor on the exhaust, so no problem to test the car on the road, but according to instructions i have to set the throttles to 9 degree, then slow down with brakes till 2400RPM all in second gear, and don't know how to measure it.

thanks!!

Ariel

There are special protractors for this. Someone on the early S registry was making perfect replicas of the factory tools for a price that was understandibly high. I think there are other tools out there that will do the job for less money.

That's why i want to avoid protactors ;)

My actual procedure is, accelerating till 2400 RPM in second gear and check the AFR.

OK, I misunderstood your question.

Are you experiencing flat spots in the powerband or something? I wouldn't really care what the AFR was at 2400 rpm as long as it wasn't super rich that it would foul the plugs. My car doesn't do much til at least 4000 rpm. Really it needs to be over 5000 for power (S cams).

I have set up a few 2.2s and 2.4s and simply adjust for ~7% CO at idle and ~7% at ~3k rpms.
No load testing, no angles.
All the ones I have set up ran pretty well.
Not saying this is right and I would be interested to see what others do.

Thanks for the advice BK, those are some around my parameteres for part load, but idle are a little bit lower, maybe i should adjust it

I am going to take measurements on the weekend, but i wanted to be sure to do the part load procedure, because as always tell here in the forum, never deviate from the sequence.

As for now, i have around 12.1 at 2400 RPM in second gear on a dynamometer, and around 13.3 at idle.

When climbing RPM with load it will reach somewhere around 11.8