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god i hope you guys sort this out eh...... i was gonna buy an rb26 for my gtst but ive decided to do the gtr camshaft swap cause the rb20 in my car is running fine and ive just spent over 3k on a turbo setup so should try and develop it a but more before i pull it out.... i also have microtech so i can adjust my ratios/timing if needed..... im keen to see how you guys go... good luck.....

and just a tip.... my mate broke his tensioner bolt on his rb20 after doing had timing belt... only problem was it happened at about 5000rpm as he diddnt realise he had over tightened it.... and the end result?? 22 bent valves so just be carefull and take ya time eh :)

I managed to throw the engine back together this morning and had just enough time before work to do some SAFC tweaks. After leaning it at low RPM quite a bit it has better, smoother throttle response. I still can't get it to idle above a couple hundred rpm. I need to find a way to get the idle speed up on the stupid thing, if I could manage to get to about 950 or so RPM I would be home free I think.

Can you tweak the idle settings with the ignition on without having the car idling already?

Thanks,

-Matt

good stuff Mabru! is it holding idle at all? or still stalling after a bit of effort.

have you taken it for much of a drive?

let me know when you have time.

i decided to get my rocker covers sprayed while its all apart. last night i managed to tear my finger right open and rip the nail off, so my poor little finger needs a break. so i wont have it back together till wed i think...

Nah Benny, same stuff so far, idles really really low then croaks.

I am going to try and adjust the idle speed a bit when I get some more time to look at it and tweak the low settings a bit. Once in a while it will idle, but it's not very common yet. I'll work it out but it takes time I guess. I promised a friend I'd do his auto-manual conversion tomorrow so there goes a chunk of my troubleshooting time!

-Matt

I did try it at first, but this whole cam issue has forced me to track down a couple problems that were pre-existing so I've gotten sidetracked a bit. The AFM plug was having intermittent contact and the water temp sensor was stuffed.

I've taken care of these two issues and now I can back on track again, I'm going to try and adjust the AAC after work this evening. As I posted earlier, leaning out the SAFC on the low RPM/low throttle made the car feel better but the idle was really really weak, to the point it would stumble and die off after a few minutes.

I'll give the AAC another go and see if I can coax it up a bit.

-Matt

WazR32GTSt

The reason it wont lean out is because the air passing through the AAC valve is still metered by the AFM. Thus the ECU injects the amount of fuel that corresponds to the AFM reading and so the A:F ratio should stay the same.

If you were to pull a vacuum hose off so the engine was sucking unmetered air it would get lean.

I think i might give up on the idea.

From what Sydney kid says, its a great upgrade with awesome results if you have an aftermarket computer to tune according the the cam change. However as i didnt have a new computer in my budget i think im going to pull the cams and just go adj pulleys.

I would love to keep them and have an average 25rwkw power upgrade, but unfortunately i dont think its gonna happen with a standard ECU.

So anyone out there with aftermarket management, mine are for sale $280 to who ever wants them. I paid $350 for them from T88 onboard, they have only done 30,000km.

Everyone else who is doing them, let me know how its going.

Ben.

The RB20 is an interference motor.. Ask Bl4ck32 all about that when his idler bolt snapped after the mechanic tensioned it too much. :)

I've had the same issue with the timing light, timing jumps about and is way way off the scale.

I put it down to a cheapish light. I also read some where a while back that you need a certian spec light. It may have been in the R32 Engine manual.

Yeah Bbenny,

I've given up for now as well, no amount of SAFC tweaking gave me an idle above stalling. I've already got the RB20 cams bolted back in now, I'll finish up in the morning and hopefully be none worse for wear. I'm sick of my car doing it's imitation of a statue!

I'm thinking that the 4 degree retard on the exhaust cam that SK recommended would make a hell of a difference.

-Matt

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