STi Time Attack 2008 - new dyno figures !!

[ScoobieWRX]

As far as messing with the AVCS Duncan i understand making changes from 0' above 5200rpm on the std cams could have some dire consequences so you will probably need something custom to give you what you want, and like you say they are big bucks.

If you feel you have gone as far as you can on the std ECU then maybe it is time for something bespoke, maybe something you could swap between like the std ECU for road use and the competition ECU for when you need it, but then again a competition ECU should be able to run several maps so i suppose there's no point swapping then.

Bit of a dilemma Duncan, i wouldn't want to be in your shoes as it's quite a decision to make. Pity there wasn't a way to completely reprogram the std ECU to work more like a competition ECU or to further enhance it's workings.

Would reprogramming using ECUTEK take it several steps further. I think on the 32-bit ECU's you can store extra maps and there is further functionality with ECUTEK. They won't sell it to the likes of me as i don't tune cars for a living and i hear they are pretty strict about it. If i could though i probably would have done so by now.

[duncan]

Ecutek does not have map switching abilities on my model year. On the other model years, it is just a boost map switching facility so no good anyway as it will not alter anything other than boost targets. As my boost is controlled by the AVCR this would have zero impact on mine.

Ecutek does not have launch control nor flat throttle shifting either so I would be worse off and have to pay for the pleasure of someone else mapping the car. An all round loss of function and waste of money for my purposes.

I am at (or very close to) the limit of a lot of the existing sensor/inputs into the ecu such as the MAF where I am regularly seeing 4.94 volts readings from a 5V sensor and this is in an already enlarged MAF tube.

There is a possibility of a speed density hack on my ECU but there is no gtee that this will be forthcoming or actually provide a benefit. I have decided that Solaris is the ecu that I will be going with shortly once their Drive By Wire module is finalised. I am hoping that this will be in a few weeks although I doubt whether it will be soon enough for TA Snetterton.

That will give me 4 distinct full maps available and combinations of these maps as alternative settings to cope with fuel changes, boost changes and lots of other things. In total I will have a 8 position preset map switch - should be more than enough. It look very complicated but it has the advantage of a full and proper (and editable) knock control strategy as well as the usual full control of everything else, LC, FFS, ALS, Logging etc

With ref to the AVCS above 5200. I already run above 0 degrees of advance from that level and above and have done for some time to good effect (or at least i think it is) There has never been a conclusive study on the impact of these on actual power IMO, most data has been at best disputable and at worst down right misleading.... To study the real impact of this would require live/real-time mapping where we can physically change the cam timing and look at the figures on the dyno to see what works. It will be very hard to prove it using the reflash method. I will try and see if there is anything worth publishing on this.

To summarise (sorry got all long winded then) :whistle: ... Gary and I both reckon that a change of ECU will provide a significant BHP gain and consistency of results. This will then make any further testing or macro-component testing easier to analyse.

[ScoobieWRX]

Interesting about the AVCS above 5200rpm, maybe the issues are with 2L engines and 16-bit ECU's.

So i suppose the only thing for it is to map to rpm as opposed to MAF in due course. Is there not a bigger MAF you can use either aftermarket or from a different Jap car??

Although i've not heard of Solaris i have just done a lookup and read some of the blurb. Looks a very ncie bit of kit but as you said...a bit complex although it seems to do everything required and then some, bar wipe your bottom.

Will be sorry to see you go from the Denso ECU tuning scene in favour of the high end stuff I'll have nobody else now on BP for me to pick their brains as it seems to me to be only you and i that do ROMRAIDER mapping.

Good luck with that :thumb:

[duncan]

Interesting about the AVCS above 5200rpm, maybe the issues are with 2L engines and 16-bit ECU's.

What issues?

[antonioo]

nice work on it 8) good power on it :thumb:

[ScoobieWRX]

Interesting about the AVCS above 5200rpm, maybe the issues are with 2L engines and 16-bit ECU's.

What issues?

Something about the more variable the cam changes at the top the more likely AFR lower down will suffer creating bottom end power/torque loss and sometimes misfiring/det in extreme cases. It may well be this only applies to 2L boxer engines. Just something i read a while back when i started looking into AVCS timing and adjustments.

You have it either low down to mid range for driveability, or higher mid range to top end for higer revving engine and more power at the upper end. You can't have it all the way across the rpm range as AFR's can't be accurately maintained both ends, and might lead to det lower end if AFR's go very lean.

On mine the AVCS remains 0' after 5200rpm although changes at that end are pretty minimal and the biggest changes occur at between 1200 and 4200rpm. It may be wrong to call it an issue but this is only what i have read and applied to the changes i've made which have been between 1500 and 4000rpm.

I've experimented with many different settings on the AVCS to try and sort out the lag i was getting and this feels like it's greatly improved, but i cannot say for sure if it's the cooler weather that's helped or the recent AVCS changes i made.

Like you said it may be subjective and there is evidence for pro's/con's but all i know is AVCS is there for a reason and it's something else to play with.

Edited to add: I've had a look a a number of modified maps i have on my PC, some from other sources across the pond, some from Japan, and other EDM/ADM/SADM modified maps, and i haven't come across one that isn't zero above 5200rpm. They are all 16-bit maps that i have looked at. I also have some 2.5L maps i haven't checked yet, i'll see what they say.

Edited to add again: I've now looked at the 2.5L modified maps i have and none of them have had the AVCS played with above 5200rpm either, so it looks like you're doing some pioneering work there Duncan :thumb:

[duncan]

http://forums.nasioc.com/forums/showthr ... 90&page=17

Not pioneering at all.

[ScoobieWRX]

That puts a very different slant on things. These yanks really seem know what they are doing and don't mind experimenting. There's plenty of theory behind it as well as putting into practice. It would seem i am probably running a little bit too much advance lower down so will have to have a rethink on my cam timing.

I never go on NASIOC, normally OSECU or ROMRAIDER but maybe i should become a member, specially after reading this. I'll have to go through that thread from start to finish.

Cheers Duncan :thumb:

[duncan]

Generally speaking there isnt a lot of real info on there, it is more bitchy than scabbynet but that thread is interesting for the amount of detail in there.

yhpm

[ScoobieWRX]

I'll sift through and pick out what i need

RTYPM, Cheers.

(Text speak...very naughty, Stuart will do me!! :lol:)