Big cams, OE manifold, way down on power.

[227bhp]

Just don't rock up asking what to do with a nail in your tyre, with your car after you put the jump leads on the wrong way or how big a compressor should be

[227bhp]

Indeed, if you don't believe us would you believe:

Max_Torque said:

to be honest these days, the only reason you'd run ITBs is to allow you to run a REALLY hairy cam! (Because the small downstream ((of the throttle plates) volume means at low speed you get a much smoother running engine as the internal EGR is prevented from getting back up into the plenum.

Modern throttles on modern plenums (big volume!) make good power these days, ITBs really are not needed ime.

if you want to do it properly, take a leaf out of BMWs book and use an M5 electronic throttle actuator to drive the throttles:

From here, but there isn't much else of use there: https://www.pistonheads.com/gassing/topic.asp?h=0&...

[227bhp]

stevesingo said:

276deg@ 0.1deg is not REALLY hairy though is it.

You still haven't answered what you are using for load on the ECU.

With 12mm of lift it is and the exhaust cam is a heck of a lot more too.
It uses Maf for load so I think you're barking up the wrong tree there i'm afraid.

[227bhp]

GreenV8S said:

Just out of curiosity, how do those runners tune when you have short and long in parallel? I'd have guessed that gave you the worst of both worlds, but presumably do somehow work. Is this a conventional arrangement?

I'm not 100% sure what you're asking there, but it's standard equipment and the cycle (as it were) is as I mentioned earlier, but at WOT. It'll use a different cycle dependent on conditions, how far the accelerator is pressed etc.
We have played with it to optimise it for our set up as obviously we're far from standard now. When we looked at the first dyno plot (with IMRC as std) I penned in the runner changeover times and they corresponded with blips on the power curve.
It's certainly not common knowledge that it acts like it does as standard.

The whole operation is like some bloke playing a huge church organ, he's got all these knobs, pedals, keys etc and can use them on their own, in conjunction with each other, at half pace or whatever else he desires to get the end result.
If you swap the bloke for the ECU and the organ the engine as a whole you realise how complex it is and why we're playing with the OE Ecu and not aftermarket. The standard engine has VVT, EGR, swirl flaps, 8 runners, DBW, knock, two Lambdas and your more normal spark and fuel control, it's also measuring traction, braking etc, it uses them all together and to different degrees too.
This is nothing special compared to others and 15yrs out of date too.

It's loud so if we do a WOT run from 2k up to 8 it sounds like an organ too as it goes through it's modes the engine note changes.
I'm not new to engines, but not great with ECUs and only have a rough overview. It's interesting how we can make a mechanical or ECU change then take it out for a run and log, if the MAF shows more air passing then we know we're making more power before we go back to the dyno.

Because it's DBW we can implement flat foot shift, downshift blip, launch control and if the car is cruise control equipped then the buttons double up as 3 different map settings, that's why I wanted to retain it.

[227bhp]

stevesingo said:

227bhp said:

stevesingo said:

276deg@ 0.1deg is not REALLY hairy though is it.

You still haven't answered what you are using for load on the ECU.

With 12mm of lift it is and the exhaust cam is a heck of a lot more too.
It uses Maf for load so I think you're barking up the wrong tree there i'm afraid.

MAF does not tolerate long duration cams. The pulse waves are disruptive to a good signal.

Pulse waves end at the bellmouth of the runners. The plenum also acts like a settling chamber, upstream of that is the throttle plate which is closed at idle, beyond that about 300mm away is the MAF, there is no way on this Earth it's being affected.

[227bhp]

dhutch said:

Do we know what engine this is yet?

It's completely irrelevant to the issues which should be being discussed. An engine is an engine, they all follow the same laws of physics and they're actually all pretty much the same inside from the same period in time (just before DI was introduced).
Manufacturers cannot afford to leave anything on the table these days.