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I totally agree with whatsisname. I am expericencing the same problems with my stock ECU as its starting to show its limits. At a dyno day, the graph was climbing rapidly, then it nosedived by about 30kw, then rocketed back up to close to 170rwkw. There was no doubt the ECU was pulling timing badly. On the road, it was like I was backing off, then flooring it again. After that, the curve was smooth again, with 1 deg less on the base timing. I am thinking of doing the knock sensor mod so the ECU doesnt panic all the time..

in regards to the AFR's, on graphs ive seen with the stock AFM, the line is more up and down and messy looking before leveling out in the top end. I just had my car tuned with a Z32 AFM and the AFRs are HEAPS smoother and flatter. Maybe they are easier to get consistent with a Z32 AFM? i dont know. i dont really care either, as long as its safe and the car goes hard is all that matters!

Well done, new found power is awesome!

Enrico,

Why can't shootout accredited dyno's be compared? I take it this was a Dyno Dynamics dyno? I've seen hundreds of cars using 4th gear and they don't hit the speed limiter on the dyno, what's different about there's? I totally agree that dyno's are a tuning tool, and that aslong as the tune is good then that's all that really matters, but it's nice to have a final reading in shootout mode so that we can all compare figures without dyno bias.

enrico i doubt your AFM is maxing out at that power. With the boost your running and the power your making it should be absolutely no problem. My stock AFM only maxed out running 18psi boost on a cold night. I could almost get away with running full boost in warmer temps with the stock AFM. Mine with the stock AFM made around 230rwkw without maxing out (unless cold air temp).

Seeing as Z32 AFMs arent real cheap, plus if you do change it, you will need a retune on your uni chip, id be sticking with the stockie until it brings you problems.

Steve is their a way to work out what voltage the stock AFM is running out without getting a fancy aftermarket computer ?

Also remind me please, what is the peak voltage again for a S1 AFM ?

peak voltage is the same for all AFAIK, S1, S2 and Z32 - 5.115V, not sure how you would check it sorry, must be some way to measure the ouput though

the difference between skyline and z32 is what airflow produces the same voltage, z32 will flow more air for the same voltage reading as a skyline afm, so for example (figure purely for demonstration) the airflow for a skyline afm may read 5.115V, but the z32 may only read 4.25V. thus greater tuning ability at higher airflow

Gts-t Vspec, I will be gettin a figure from tilbrooks when the boost is upped and cam gear is dialled in. But until then, u will have to wait. Of course I would like a dyno read out in shootout mode, cos i know on this particular dyno, it is one of the lowest reading in SA. So obvioulsy i want a higher reading :D So i can compare to u.

Also, how come whatisname commented that our dynos were very similar in curve, then he mentioned that he was maxing out afm. Thats what has gotten me confused.

Another thing, Last night while driving (9ish), the car felt good, but when i was drivin another hour or so later (11.30), it felt awesome, like heaps more pulling power. Could this be what you guys state at maxin out afm, or would i feel it in a jerk of some sort. Or it could of been cos the colder air..

peak voltage is the same for all AFAIK, S1, S2 and Z32 - 5.115V, not sure how you would check it sorry, must be some way to measure the ouput though
Do you know if anything can be plugged in on a dyno and tested that way? I wouldn't mind knowing what mine is running at just to see if its causing a bottleneck.
Do you know if anything can be plugged in on a dyno and tested that way? I wouldn't mind knowing what mine is running at just to see if its causing a bottleneck.

A real budget way, is next time you are on a dyno, just use a multimeter to measure the voltage output from the signal line on your AFM...or perhaps more conveniently get a cheap batter voltage gauge (Jaycar???) and wire it up, you will soon know what its peaking at, some of the cheaper voltage gauges may even have a peak recall.

Haha the thing is Benm, u cant compare dynos, just how u have experience with some readin 203 for u then others at 180...

I dont see how people can still think they are compareable. Anyway, ill just use my digi multimeter and see what happens on a dyno run.

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