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I wouldn't be so sure with that, man. Terry had huge timing issues on his blue R34 GTR (PFC) years ago.

Think about how many PFCs exist in RBs around the world without problemo in that department due to the speed of the thing itself...

None have become damaged or otherwise... If it was the problem would be stupidly well documented for such a popular piece of equipment

But isn't the problem with the design if the engine itself? Ever seen an RB in a dyno without the cam gear cover on? The belt flops around like nothing else. That "flopping around" must result in some sort of timing fluctuations, would it not? Timing taken off a sensor which is driven by a big rubber band won't be doing anyone any favours... Enter the crank trigger.

It's only been in the last 3 or so years the timing variance/scatter/whatever you want to call it has really been spoken about.

It would be interesting to ask the supra guys if they have the same issues as us with FC's. They have a crank trigger from factory.

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It's got to do with the optical sensor. I have seen it with my own eyes. We were bench testing an optical sensor and synch capturing the cas signal on a haltec and it was jumping all over the place. We mocked up a 12-1 hall effect cas and the signal was perfect. As nismoid mentioned it may be the new ecu's resolution or the pfc can some how read the 360 disc with its 6 triggers that are different widths that let it more accurately localise the engine phase and position in the rotation. Given all that I think the optical pick ups is the problem because even the aem 24-1 with the factory optical sensors has sync problems with the haltec

It's got to do with the optical sensor. I have seen it with my own eyes. We were bench testing an optical sensor and synch capturing the cas signal on a haltec and it was jumping all over the place. We mocked up a 12-1 hall effect cas and the signal was perfect. As nismoid mentioned it may be the new ecu's resolution or the pfc can some how read the 360 disc with its 6 triggers that are different widths that let it more accurately localise the engine phase and position in the rotation. Given all that I think the optical pick ups is the problem because even the aem 24-1 with the factory optical sensors has sync problems with the haltec

Would this timing problem discredit the advantages of going to the haltec

Not at all, it's just there is a problem that exists with all modern ecus and the rb cas. So as a result they are not plug n play as marketed, where the pfc is. So the buyer needs to be aware of the issues and potentially need to invest in a crank trigger. That's all

Just do your homework before u make the investment. Being through it all myself and knowing of many others with the same issues, and hearing the same thing across the world, if I had my time again I would have kept the pfc. No point having all the bells and whistles if the the basic stuff like air, fuel and spark can't be managed properly and consistently, especially if they market something as a plug n play ecu and then recommend a crank trigger to solve the issues.

But isn't the problem with the design if the engine itself? Ever seen an RB in a dyno without the cam gear cover on? The belt flops around like nothing else. That "flopping around" must result in some sort of timing fluctuations, would it not? Timing taken off a sensor which is driven by a big rubber band won't be doing anyone any favours... Enter the crank trigger.

What this does at high RPM is produce jitter in the RPM signal. It means you might bounce from 1 cell to the next on your map. If you are making 400kW and your tune is highly critical then this could be enough to ruin your day. If you are tuned conservatively it doesn't matter. That's the "it depends". It depends on what your margin is on the tune.

Also, I read elsewhere on SAU the problem was worse with aftermarket "performance" timing belts and that the OEM Nissan belt doesn't cause as much jitter. Seems like the factory belt having a bit more "give" in it is working in your favour in this scenario.

It's not about bouncing from one cell to the next.

It's the fact the ecu thinks the engine is either spinning faster or slower than it actually is and incorrectly commands timing.

It seems like the ecu manufacturer s should be able to write into their code a limit on how quickly the engine can change revs, and apply a smoothing function to the rev input. That would mean the jitter created would simply be smoothed out in the software and happy days.

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Thats right. Actually what happens is the edges of the home triggers and the cam position triggers cross over as the engine revs rise and fall, Therefore you get spark and fuel firing at the wrong time. Either you go lean or rich. The variance can change from day to day too. As what happened with my mates pretty much stock vl with a 35/40, one week it was fine the next thing it retarded by 15 degrees. at the time he was logging and we saw the events change in the rev sync log.Basically the home signal was changing its position by 6-7 cam position pulses. Interestingly he got an old motec from a mate that was obviously a slower ecu and it worked with no issue even close to what he was experiencing except for a few acceptable variations up top.

But isn't the problem with the design if the engine itself? Ever seen an RB in a dyno without the cam gear cover on? The belt flops around like nothing else. That "flopping around" must result in some sort of timing fluctuations, would it not? Timing taken off a sensor which is driven by a big rubber band won't be doing anyone any favours... Enter the crank trigger.

It's only been in the last 3 or so years the timing variance/scatter/whatever you want to call it has really been spoken about.

It would be interesting to ask the supra guys if they have the same issues as us with FC's. They have a crank trigger from factory.

Of course it is - such is the joy of playing with 20yo motors.

But talking crank triggers and so on isn't just talking a simple ECU change, which in itself isn't cheap. It's now going towards a 3-4k+++ adventure.

The issue has always been there - but why has it come about? Because of the ECU speed. You didn't see it with the older/slower ones in such a prevalent manner

Not at all, it's just there is a problem that exists with all modern ecus and the rb cas. So as a result they are not plug n play as marketed, where the pfc is. So the buyer needs to be aware of the issues and potentially need to invest in a crank trigger. That's all

Yeah it doesn't mean a non-recommendation. For most people the issue won't be there as a run of the mill set-up won't bring up these problems in most cases. Certainly not a common problem with a Haltech, plenty of people around here using them without a problem at all for their setup. Same for all newer ECUs.

Just that the issue exists, think about it as part of the choice, if you've got a bit power dealio coming

There is no way anyone would want to drive a hq every day over a brand new car and anyone who says they would is a liar

You're going to have to call me a liar then. I would take a HQ over a VF any day. HQ to the same value of mods and resto as a VF is my only stipulation. Coolness factor + one gazillion in the HQ. Coolness factor of the oversized Cruze = zero.

Yes I am, cause the comfort level refinement level and safety level of the vf over the hq means for "every day use" no one will pick the hq

Cause while the hq might be oh how cool is this for 3 weeks, the vf will still be comfortable and refined after that 3 weeks when the reality kicks in that the hq is actually shit to drive every day

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Right. My R32 is so loud inside that I can not hear when my phone rings, have to turn the stereo up to the distortion limit to hear any music, has no air conditioning, firm suspension settings that mean you have to steer it every moment, uses heaps of fuel and blows my tyre budget every 6 months.

I drive it every day and would choose it over a VF. I can afford to go out and buy whatever the top shelf Coomode is right now. I won't do it, not least because it's a waste of money, but primarily because I don't want one, even though now is just about the last chance we're going to get to be able to buy a 6.x litre V8 monster RWD. If I was to spend that sort of money, then a nice HQ, which I would daily, might well be on the list. Or a suitable Camaro or something else muscley from back then. I like cars that are rough and lumpy.

I've owned old Holdens (including HQ and older), Commodores, Alfas and the R32. I think the older cars that are actively trying to kill you while driving them are a lot more interesting than the plasticated ESP'd ABS'd traction controlled parking sensored autoparking shitboxen that are available now, no matter how good their air-con or their GenY weenie entertainment systems are.

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Had a 116 GTV2.0. Red with plastic bumpers. Was mostly stock, mostly looked OK but mostly broken, like most of them. I rebuilt the engine with some sensible upgrades so it made a reasonable amount more power, had Konis and the like on it. Was a great little thing to drive. Used to spend an unreasonable amount of money on tailshaft donuts though, and would have cost more than I spent buying the R32 to make it genuinely fast......and then it still would have had Italian electrics.

Right. My R32 is so loud inside that I can not hear when my phone rings, have to turn the stereo up to the distortion limit to hear any music, has no air conditioning, firm suspension settings that mean you have to steer it every moment, uses heaps of fuel and blows my tyre budget every 6 months.

I drive it every day and would choose it over a VF. I can afford to go out and buy whatever the top shelf Coomode is right now. I won't do it, not least because it's a waste of money, but primarily because I don't want one, even though now is just about the last chance we're going to get to be able to buy a 6.x litre V8 monster RWD. If I was to spend that sort of money, then a nice HQ, which I would daily, might well be on the list. Or a suitable Camaro or something else muscley from back then. I like cars that are rough and lumpy.

I've owned old Holdens (including HQ and older), Commodores, Alfas and the R32. I think the older cars that are actively trying to kill you while driving them are a lot more interesting than the plasticated ESP'd ABS'd traction controlled parking sensored autoparking shitboxen that are available now, no matter how good their air-con or their GenY weenie entertainment systems are.

If there was ever a post that was taken so far out of context it's this one. You know exactly the point Brett is trying to make!

  • Like 1

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