All the way on stock internals....

[aaronjb]

10K !! What happened to your rev limiter. Did dropping it into the wrong gear mean even the ecu couldnt stop it spinning to that rpm?

Like Jon said - at that point it's the car that's turning the engine, so there's zip the ECU can do (unless it could electronically disengage the clutch, that is - or prevent you ever selecting the wrong cogs in the first place, like the SMT on the Roadster) - even if you switched the engine off, it'd still be turning at x0,000rpm..

Would then mapper need to run it richer in those cylinders that get hotter then? Or am I way off base?

You'd need some very trick engine management to do that - I don't know if even the top-of-the-line MoTeC stuff can run individual fuel maps for each injector (though I very much doubt it). You could run a weird-ass fuelling setup, with an RRFPR on each injector, I suppose and then up the fuel pressure (or rising ratio) a little on the lean-tending cylinders.. that might work.

Better off sorting the root cause, though, than covering it with fuelling - redesign the intake if that's the weak spot, or the fuel rail (say, twin outer feed to center return) if that's the weak spot..

(That's all based on my knowledge of other cars, naturally, but it should hold true on the 3S-GTE as well)

[ENSMR2]

10K !! What happened to your rev limiter. Did dropping it into the wrong gear mean even the ecu couldnt stop it spinning to that rpm?

Like Jon said - at that point it's the car that's turning the engine, so there's zip the ECU can do (unless it could electronically disengage the clutch, that is - or prevent you ever selecting the wrong cogs in the first place, like the SMT on the Roadster) - even if you switched the engine off, it'd still be turning at x0,000rpm..

I wasnt sure hence why I asked. Cheers.

Would then mapper need to run it richer in those cylinders that get hotter then? Or am I way off base?

You'd need some very trick engine management to do that - I don't know if even the top-of-the-line MoTeC stuff can run individual fuel maps for each injector (though I very much doubt it). You could run a weird-ass fuelling setup, with an RRFPR on each injector, I suppose and then up the fuel pressure (or rising ratio) a little on the lean-tending cylinders.. that might work.

Better off sorting the root cause, though, than covering it with fuelling - redesign the intake if that's the weak spot, or the fuel rail (say, twin outer feed to center return) if that's the weak spot..

(That's all based on my knowledge of other cars, naturally, but it should hold true on the 3S-GTE as well)

Sounds very hard to accomplish. Maybe the MoTeCs can do something similar

[aaronjb]

Sounds very hard to accomplish. Maybe the MoTeCs can do something similar

Individual fuel maps would be extremely hard to accomplish I think - but I imagine there are systems to do it (I wouldn't mind putting money down that things like F1 cars run per-cylinder fuel maps, though I have nothing to base that on other than the amount of power they extract from an NA engine )..

Then again, the easiest thing is just to run a slightly more conservative state of tune so you're not pushing the engine quite so hard.. so if you're going down the road where you're pushing those iffy cylinders that hard you're obviously already at the point of tuning for that last nth of a bhp - so money (and complexity) is probably of little object at that point

Like I say, much easier to rework the intake manifold (get it flow matched if it's not quite right) or the fuelling system if it's not maintaining equal pressure to all injectors.. and probably more effective too (if you can run all four cylinders at 10/10ths you'll get more power than running with, say, two cylinders that you can only push to 9/10ths - not to mention less stress on the crank I should think)

E&OE, IMHO etc etc

[MR2Mania]

You'd need some very trick engine management to do that - I don't know if even the top-of-the-line MoTeC stuff can run individual fuel maps for each injector (though I very much doubt it). You could run a weird-ass fuelling setup, with an RRFPR on each injector, I suppose and then up the fuel pressure (or rising ratio) a little on the lean-tending cylinders.. that might work.

Actually, my MoTeC M800 *can* have individual cylinder trims, not only for fueling but also ignition. I'm pretty sure even the "basic" M4 can do this too, although I'd have to check.

Incidentally, the latest "alpha" release firmware for the M400/M600/M800 ECUs effectively gives you LOADS of maps for both fueling and ignition (in a similar way to the best OEM ECUs currently around). Basically, instead of having air temp or other compensation trims, instead it just jumps to another map. One of the main reasons why MoTeC can't release it yet is because very few mappers will be able to get their heads around it without having to spend hours and hours relearning how they go about mapping an engine.

There's a reason why I love MoTeC products so much!

Oh, even if the MoTeC didn't have such compensations, as Enis suggested, you can just run a richer map alround to cover any cylinders that may run leaner. A lot of tuners already do this (some OVERDO it though, IMHO).

So you see? No manifold problem!

Regarding F1 engines, here's a bit of trivia for you. As soon as you even BRUSH the throttle, EGTs go WAY past 1200C! In comparison, on even the best built performance engine that we're likely to get our hands on, anything more than 1000C is too much!!

[V8Killer]

Am pretty sure the M400, M800 and even the M4 have a fuel trimming feature, which allows you to trim the fuel per cylinder. In-fact most aftermarket ECUs do this. The new Autronic can do this too as can the Gems.

[ENSMR2]

So which cylinders should be run richer? Or will that depend on the individual build/setup etc?

as Enis suggested, you can just run a richer map alround to cover any cylinders that may run leaner.

Yeah, got something right lol.

[MR2Mania]

So which cylinders should be run richer? Or will that depend on the individual build/setup etc?

To be honest, it'd be guesswork unless you had an EGT gauge per cylinder, but more ideally a way of reading lambda for each cylinder (not easy to do, as the temps at the points where you'd be trying to measure lambda for each cylinder will be too much for a sensor for any extended amount of time). I guess if you were a WRC team (or other top level motorsport outfit) you might consider doing this, as it would mean you could map each cylinder to be fueling just spot on so that you extract every last ounce of power out of the engine, but to be fair, the said teams would likely have the engine absolutely balanced for flow and such things to within a nat's whisker so they probably wouldn't need to have all these individual cylinder sensors to start with.

In the real world, you'd just run a bit richer than the optimum, which on a turbo engine happens to be 12.4:1 (very few tuners map in the 12s, though). The Americans generally map in the high 11s and sometimes the 10s (most widebands don't read richer 10s, so you don't want to overdo it).

Yeah, got something right lol.

Mate, you're showing more logic here than most!


Incidentally, looking at the US MoTeC site, it appears that even the base MoTeC M4 ECU can do individual cylinder trimming, but needs the "advanced tuning" option enabled (at extra cost, about £250 last time I checked). Here's the quote from their site:

The Advanced Tuning Option gives many extra features including traction control, the ability to configure the ECU to your existing sensors, user definable load and rpm sites, 512Kb of on board data logging, Fuel Secondary Load Table, 3D Individual Cylinder Trim tables, Acceleration Advance, 3D Dwell time table, Traction Control and Launch Control, Wideband Lambda Control, Gear Change Ignition Cut, Anti-lag, Gear Detection and Ground Speed Limiting.

Personally, I don't think that's totally correct though, as you can configure the ECU for many different sensors WITHOUT the advanced option AFAIK.

[Andy F]

Even my basic M4 has cylinder trims

The new Motec can also pulse solenoids, (fast enough) so you can control Nos and map it correctly!!
muts nuts

[ENSMR2]

So which cylinders should be run richer? Or will that depend on the individual build/setup etc?

To be honest, it'd be guesswork unless you had an EGT gauge per cylinder, but more ideally a way of reading lambda for each cylinder (not easy to do, as the temps at the points where you'd be trying to measure lambda for each cylinder will be too much for a sensor for any extended amount of time). I guess if you were a WRC team (or other top level motorsport outfit) you might consider doing this, as it would mean you could map each cylinder to be fueling just spot on so that you extract every last ounce of power out of the engine, but to be fair, the said teams would likely have the engine absolutely balanced for flow and such things to within a nat's whisker so they probably wouldn't need to have all these individual cylinder sensors to start with.

In the real world, you'd just run a bit richer than the optimum, which on a turbo engine happens to be 12.4:1 (very few tuners map in the 12s, though). The Americans generally map in the high 11s and sometimes the 10s (most widebands don't read richer 10s, so you don't want to overdo it).

Yeah, got something right lol.

Mate, you're showing more logic here than most!


Incidentally, looking at the US MoTeC site, it appears that even the base MoTeC M4 ECU can do individual cylinder trimming, but needs the "advanced tuning" option enabled (at extra cost, about £250 last time I checked). Here's the quote from their site:

The Advanced Tuning Option gives many extra features including traction control, the ability to configure the ECU to your existing sensors, user definable load and rpm sites, 512Kb of on board data logging, Fuel Secondary Load Table, 3D Individual Cylinder Trim tables, Acceleration Advance, 3D Dwell time table, Traction Control and Launch Control, Wideband Lambda Control, Gear Change Ignition Cut, Anti-lag, Gear Detection and Ground Speed Limiting.

Personally, I don't think that's totally correct though, as you can configure the ECU for many different sensors WITHOUT the advanced option AFAIK.

Top info! Thats why we need you around here dude!

Thanks for the comment lol.

The new Motec can also pulse solenoids, (fast enough) so you can control Nos and map it correctly!!
muts nuts

Anyone heard of solenoid controlled valves? When my mate was at ford they developed and engine with solenoid controlled valves. No need for cams. If something like this could be done we'd get perfect timing etc.

[MR2Mania]

Anyone heard of solenoid controlled valves? When my mate was at ford they developed and engine with solenoid controlled valves. No need for cams. If something like this could be done we'd get perfect timing etc.

Do you mean hydraulically driven valves? If I'm not mistaken, that's what kinda valves they've got in F1 engines, so that they can rev so high without valve float. That's why F1 cars rely so much on hydraulic control systems (these hydraulics drive things like the gearchange, etc, too).

To have something like that on a road car will take some development to create a package that is affordable to produce on a mass production scale. Mind you, Honda are probably not far off this with the valvetrain systems they've been developing over the last couple of decades.

Incidentally, the solenoid valves that Andy referred to also includes things like boost control valves. That's basically what the stock VSV and other electronic boost control valves are - electronic solenoids that are pulsed at a given frequency in order to bleed off the required amount of air to give a certain level of boost. The MoTeC is good at controlling valves like this, and hence why it makes for a damn good boost controller (in this respect, I personally reckon that the MoTeC would out-perform all the usual aftermarket electronic boost controllers that you see).

[aaronjb]

Do you mean hydraulically driven valves? If I'm not mistaken, that's what kinda valves they've got in F1 engines, so that they can rev so high without valve float.

Pretty sure you're right, there (but you knew that already )..

Interesting about the MoTeC btw - apparently I didn't read the specs well enough I haven't seen mention of it in any other ECU literature though - happen to know if the Emanage or Emanage Ultimate can do individual cylinder trims? (Just out of interest, really).

BTW - regarding EGTs.. All of the 1ZZ-FE turbo conversion folks that are running EGT sensors pre-turbo are seeing over 1000C on a pretty regular basis.. I was quite shocked (and a touch worried!), but it seems to be the norm

Confused me somewhat - especially on an engine never designed to be turboed, but apparently EGTs weren't all that much lower when it was an NA.. (I'm actually quite tempted to tap one of my two EGT guages into the manifold, since they're not being used in the 300ZX right now, just to satisfy my own curiosity)

[MR2Mania]

BTW - regarding EGTs.. All of the 1ZZ-FE turbo conversion folks that are running EGT sensors pre-turbo are seeing over 1000C on a pretty regular basis.. I was quite shocked (and a touch worried!), but it seems to be the norm

Mate, that don't seem right! The engines that run the hottest are the rotary/Wankel engine, hence why they also need to run that little bit richer than regular engines. I too have my EGT before the manifold and the highest I've been is high 900s when it was running a tad on the lean side. Which reminds me, Evo engines for some reason tend to run about 100C cooler than other 4-cyl turbo engines for the same given conditions. Weird....

[MR2Mania]

Interesting about the MoTeC btw - apparently I didn't read the specs well enough I haven't seen mention of it in any other ECU literature though - happen to know if the Emanage or Emanage Ultimate can do individual cylinder trims? (Just out of interest, really).

Mate, the basic Emanage is just a piggyback (so won't be able to do individual cylinder stuff), and I remember when speaking to a certain Unichip expert I know (a *real* one, not a claimed one!! ), he wasn't that impressed with it and he even went as far as to explain where and how the Unichip was considerably better. I don't know much about the Ultimate, though, so can't comment.

[lower]

I think the solenoid comment refers to solenoid operated intake and extract valves. Most of the manufacturers have been playing around with these because it would mean you could get much better control of fueling for both power and economy. But the solenoids need a significant amount of power to run and really need to run at 48V which is a problem for cars at the moment.

[Bender Unit]

Guys, that is CLASSIC ringland damage, caused by the excess boost. No det there (can you see any pin holes, or worse, melted sections?).

Take it for what it really is - a classic case of overboosting cracking the stock pistons.

Problem is Dino the picture you see posted by Screech is taken by me, he has another piston which is also cracked in the same manor. He managed to have two pistons dropped - however the failure apparently happened at 8psi? So either the pistons cracked but held out and then failed or somthing like detonation shocked them and caused them to crack. The pistons were before failure taken up quite high in the boost range from what I recall.

Cheers

James

[ENSMR2]

I think the solenoid comment refers to solenoid operated intake and extract valves. Most of the manufacturers have been playing around with these because it would mean you could get much better control of fueling for both power and economy. But the solenoids need a significant amount of power to run and really need to run at 48V which is a problem for cars at the moment.

Yes, thats it.

It was a one off engine done by ford when my mate was there. There were no plans for any mass production.

[aaronjb]

Mate, that don't seem right!

I know - that's what I said I was adamant that they shouldn't be as high as that.. but everyone with an EGT guage reads roughly the same values - like I say, even stock NA form they're well up there..

[Fred]

F1 cars use pneumatics to open and close the valves , this system isn't being used on road cars because of the incredibly high noise levels produced .

Ducatis use the cam to open and close the valves , removing the need for valve springs as used in the conventional system .

/trivia

[MR2Mania]

F1 cars use pneumatics to open and close the valves , this system isn't being used on road cars because of the incredibly high noise levels produced .

That's the one!!! =D> That's why I didn't say for sure, because the one thing that was niggling me as I posted it was that I doubted F1 teams would want to add the weight of fluids needed for a hydraulic setup.

They use some kind of inert gas don't they? Or something that won't suffer extreme temperature changes or be affected by moisture, etc? ISTR that these systems have proven to be Toyota's Achilles heel this season, with Jordan suffering a few failures that were done to the pneumatics.

Ducatis use the cam to open and close the valves , removing the need for valve springs as used in the conventional system .

That's interesting! When I get a spare couple of hours I'll have to try and look that up and see exactly how that works mechanically. Thanks for that info!

I think the solenoid comment refers to solenoid operated intake and extract valves. Most of the manufacturers have been playing around with these because it would mean you could get much better control of fueling for both power and economy. But the solenoids need a significant amount of power to run and really need to run at 48V which is a problem for cars at the moment.

So how does such a system work? Is the solenoid used for instantly banging the valves open and shut, rather than pulsing, and hence why it can handle highish revs? I'm not too great on electronic devices, but I wonder if I'm on the right lines about, I wonder if you could vary the distance that the valve is pushed by, hence an ECU could not only change duration of the valves but could also control lift? Interesting system, but one that I'd imagine would take ages to perfect.

[MR2Mania]

Problem is Dino the picture you see posted by Screech is taken by me, he has another piston which is also cracked in the same manor. He managed to have two pistons dropped - however the failure apparently happened at 8psi? So either the pistons cracked but held out and then failed or somthing like detonation shocked them and caused them to crack.

Was there any sign of any pin dents? You could be right. What about from thrusting? Since you built your engine recently, do you remember which side is the thrust side on the 3SGTE? Mind you, if that was the case, you'd have noticed other anomalies, like a bent crank or ovalled bearings. Other than that, did the pistons look OK?

The pistons were before failure taken up quite high in the boost range from what I recall.

Mate, I've now re-read that a few times, and don't understand what you mean (I can't understand your sentence)?