Rb26 Cam Gears

[djr81]

Sorry to re-ask a question that has doubtless been asked before (Search turned up nothing, however) but:

If, for example I set the cam gears to +4 degrees inelt & -2 degrees exhaust does this mean the timing needs to go to 16 degrees BTDC on the crank.

Can anyone with these adjustable gears on a stock RB26 (+ pods + exhaust + 1 bar boost) confirm these number to be about right?

I had this all figured out once, but old age & infirmary makes me forget.

[Beer Baron]

from memory my inlet is advanced maybe 6 and exhaust retarded about 4. gave a nice lumpy idle, and heaps more power everywhere. I don't think you need to do anything to correct the timing. you just adjust the cam timing at the gear and leave everything else alone. it's been nearly 2 years since mine were done though, so if somone else has a better memory than me, listen to them!

[djr81]

I assumed you had to as the CAS is driven off the exhuast cam.

[Full-Race Geoff]

which cams and which turbo setup do you have?

[djr81]

which cams and which turbo setup do you have?

Presently stock & stock.

[Beer Baron]

yeah sorry, since you remove the cas to do it I assumed you will re-set it when re-fitted. but you still want the ign timing to be 20 base, so that doesn't change. unless someone can tell me I'm wrong! 2 years is a long time for my poor memory!

[The Mafia]

keen to see results!

[femno]

Yeah you need to reset the timing after you change the ex cam position, even if you put the cas back in the exact same spot it will be wrong because you have shifted the cam. Set at 20 base.

[djr81]

Yeah you need to reset the timing after you change the ex cam position, even if you put the cas back in the exact same spot it will be wrong because you have shifted the cam. Set at 20 base.

Thanks Femno & Baron. Put the things in on the weekend. Adjusted the CAS so the timing light was indicating the same as the PFC handset.

Results? Well nothing much discernable from the data logger. Problem being that turbo motors are greatly influend by ambient air temps & I can't log these. Subjectively it felt much better through 4000rpm and seemed to spool up a little quicker. So I am happy with the results.

[Beer Baron]

mine made a very nice gain of around 30rwkw with nothing else touched at all.

I'll find the graph...

[r33_racer]

fark...30kws is good power, made just with playing with cam gears.

[Beer Baron]

ok, found the graph. I overstated a bit. it was 26kw gain. and absolutely nothing else touched except for the cam gears. the ebc settings, and power FC settings were left alone. at one point there was even more top end, but not as fat in the midrange. i preffered more in the mid range so I stayed with the result you see below.

[djr81]

Nice result.

I should add too that the idle doesn't appear to be adversely affected.

[Beer Baron]

yeah it was a good result. that was 2 years ago, car is a bit different now and with about 20rwkw more. my idle was definately affected. but I love it. sounds much tougher now. poor mans cam change I tells ya.

[nsta]

how easy is it to fit cam gears to a stock 26? im doing my timing belt at the same time if i go ahead with it.

thanks,

[STATUS]

Timing wont change as the inert part of the gera stays in the same position in relation to the crank.. only the outer advances or retards.

Beware too as i have used a few of the cheap ones lately and found them to be timed way out IE 0degrees is actually closer to 8 (cant remmember if it was adv or ret) so if you getting cheapies then check the cam timing first.

I first found it on AROSPEED Sr20 gears where they needed to be advanced about 9-10 just to get lost power back.....