[Mk2] [Turbo] A question for anyone running 264 cams with standard rev 3 ECU

[Danbob]

Is anybody running a stock rev3 ecu with HKS 264 cams?

If so,. Did you set cam timing to the HKS cam card?

And with that timing does your car idle ok? Does it stall at all when off throttle


I am trying to diagnose why my engine hunts for idle and stalls when off throttle, checked all the usual things, want to check if it's a known fact that the stock ECU can or can't deal with those cams without problems.

Thanks
Dan

[Milo_101]

What are the cams set at at the cam gears?
It really depends on a couple of factors, but typically the idle quality will suffer the more you play with the cams on the stock ecu.

Besides, setting your cams per HKS cam card is good and all, but you really should go to the dyno and adjust them there and see what combo makes the best power/ or generates the torque curve of your choice.

THe hks cam card might not best setting for your particular engine.

[Danbob]

Hi, thanks for your input.

But really I just want somebody who is running 264 cams in a rev 3 engine on stock ECU to tell me if their engine can idle at stock idle rpm, in order to aid my diagnostic process.


Are you running 264 cams in a rev3 with a stock ECU?

[Milo_101]

No, But I was running GSC 268 High lift cams on stock ecu at one point.
But i hadn't degreed them on the stock ecu as I knew the idle would suffer.

Like I said before, most people install them straight up (@0) while still on the stock ecu, because the more you adjust them, the more your idle quality will suffer.

Basically you can degree them to straight up (@0) and your engine will idle like normal again, until you get a standalone ecu and them adjust them and you can tune the mixture or raise idle speed a bit for it to idle properly.

I'd rather have an engine that makes 15 less hp/tq but has good idle quality and no stalling off-throttle, than the other way around, don't know about you.

On the stock ecu, there is just no way around it.

[Danbob]

OK, that is much more useful information, thanks!

I'm not running stock ECU permanently, just using it to run in my freshly built engine and want to ensure everything is running correctly mechanically and electrically first to have a stable platform from which to start tuning with the standalone. (As everything is new to the car)

However the car will stall out once warm at idle, which is preventing me from moving on until I diagnose it. So far I have already checked everything vacuum related, exhaust leaks and electrical, so was starting to consider valve timing, and valve clearance as possibilities.


That's why I just needed to know if other people had ran these cams (or similar) with stock Rev 3 ECU, To check it was actual possible to get it to idle with these cams.


I had maybe naively assumed that the cam card would specify the neutral values to set the cams as a baseline before tuning so set them there.
I'll swing them back to zero this weekend and see if that solves it. Will owe you one if it does.



Cheers
Dan

[jimGTS]

Usually when a 2 is sat doing nothing for a while, the iscv can sometimes stick open or shut, causing very similar systems.

Either high idle, or stalling when at a stop.

Worth a check and cleaning it out.
If you don't want to even go to dismantling hassle, you can check its opening and closing by feeding it 12v and listening to it. Check bgb for the pins.

[jimGTS]

Oh I had 264s on my old car, both inlet and exhaust adjusted on cam wheel to, so even more aggressive, and I had no problems with idle on stock Ecu when I was testing something.

[Danbob]

Hi Jim, yeah ISCV was the first thing I checked. Confirmed it's physically functional, electrically in spec and the 12v supply and harness to the ECU is OK. Got a new ECU on the way in the post to rule that out aswell but don't have high hopes that'll fix it.

Had you degreed your 264s all the way to the cam card specs (103 ex, 110 in)?

Was it on a rev 2 out rev 3? The us boys imply that the AFM ECU copes with cam changes better.

Cheers
Dan

[jimGTS]

This was on my old rev5 turbo.
Car came with them installed already. I assume they were installed straight up and adjusted with cam gears for a more agressive setup. Even that wasn't enough to effect the oem ecu. That I can remember anyways. We are talking 5+ years ago.

Sorry I can't be any more help than that.
I have considered getting some 264s, where did you get them?

[Danbob]

Mine came with an engine I bought and had to strip down for parts as the block was no good.

Ok, if they were only adjusted a couple degrees on the cam gears and idled fine it's possible that what Milo is saying is still my problem and the hks cam card specs are too far out for it to idle properly.

They have come out quite far from the 0 setting on the gears. Around 8 degrees retard on exhaust and 2 degrees retard on intake, which is comparable to what I've seen other people state they have ended up with when setting hks cam's to 103/110.


Hopefully when I stick then to zero on the cam gears tomorrow it will have an effect prove out that the engine is healthy and then I can move them back again when tuming properly