EVO9 Mivec trouble

[Filin]

hi guys,

looking for the help with tune EVO9. I install 12 teeth trigger disk, all work fine but Mivec does not work. I removed 3 teeth from intake cam and left only 1 which is nearest to the cam sensor in TDC. VVC start is around 4.5 teeth, but I am not able to solve VVC range, VVC Modulo Div and other parameters

thank you in advance

Dima

[PQatPIT]

Is this 12-teeth trigger wheel on crank? If yes then much better solution is installing a 36-1, 36-2 or 60-2 trigger wheel instead. This way cam tooth significant edge has no chance of moving too much compared to crank teeth significant edge.

With 12 even teeth crank wheel VVC cam tooth has a chance to move too much and then ecu puts igniton and injection events 30 degrees too late or too early. With missing tooth strategy this is avoided.

[Filin]

Thank you for advise but the 12 teeth trigger is installed and I want to play with it. The mivec range moving is 1 teeth, but how can I calc CAM control range to find out cam range and Cam start? Let me know please

[RickS]

Hi Dima,
OK, a 12 tooth timing wheel has been fitted, but there really was no need as there is really very little advantage in the extra teeth.

In effect, with the advanced tooth at ~50deg BTDC, the system has about 6 teeth per rev.
Comparing the performance with the Evo X, or 2002 Sti, the gains are small, about 1degree of VVC resolution.

If it is really neccessary to fit a new wheel, then an Evo X, arrangement could be used in total and the settings converted from Evo X. The cam positions are determined by capturing the relevant cam timing edge and scaling it into degrees:
Camn Angle = Sync Tooth n + (Cam#n - Crank)/Tooth time (result in teeth.)
Camn ADV = (Cam#n Angle - Cam#n Start) × Cam range (result in degrees.)
Cam range = (degrees/tooth)/Cam control range %.

Hope that this helps and good luck.
RickS

[Filin]

Thank you for reply, but what is Cam control range%. Is this part of Mivec moving from 720degr in %? Let me know please.

[RickS]

Cam Range/VVC Range Option = °/t = degrees per tooth....
Number of internal teeth to give nominal 80°valve range. Usable range 10°-70°.

It looks like someone queried this before.... See....

http://www.gems.co.uk/gemsforum/viewtopic.php?f=6&t=81

BR
RickS

PS. There is also a post in the FAQ section of the forum that details how to setup VVC for EVO 9 should you need a refresher!...... See....

http://www.gems.co.uk/gemsforum/viewtop ... f=13&t=613

[Filin]

Thank you very much! All works well)

[RickS]

You're welcome and I'm glad that you are happy with the result.

A copy of the .CAL would be a worthy addition to our 'special' archive. A copy to the tech(dot)support(at)gems.co.uk email address would be appreciated.

Also, if you wouldn't mind, I would like to see some telemetry logs of the VVC.

Best Regards
RickS