MIVEC tuning
You can run a little more timing with less MIVEC once the turbo is lit off. It really is cam and combo dependent though. I can tell with S2s it seems tapering it off and adding the timing in is better than something like Cosworths that need to be kept advanced for awhile to keep them making torque.
aaron
aaron
I've been fiddling more with MIVEC at high boost. At first I thought that less MIVEC at high boost was beneficial, but after fiddling more, I'm getting best gains by keeping MIVEC maxed out at 28.8 deg until about 5K rpm even with 27 psi of boost and a relatively restrictive exhaust (stock O2 housing, 100 cell cat).
The thing that was concerning me is that there might be charge flow reversion if the intake was opened too soon because of high residual pressure in the cylinder. In a datalog, this would show up as either no increase in load with more MIVEC or possibly even a decrease in load with more MIVEC (because load scales with airflow). However, even at 27 psi, I get higher loads as MIVEC is increased all the way up to 28.8 deg. Torque is better as well out to 5K rpm. Out past 5K rpm, I need to do more testing to figure out what is working best.
The thing that was concerning me is that there might be charge flow reversion if the intake was opened too soon because of high residual pressure in the cylinder. In a datalog, this would show up as either no increase in load with more MIVEC or possibly even a decrease in load with more MIVEC (because load scales with airflow). However, even at 27 psi, I get higher loads as MIVEC is increased all the way up to 28.8 deg. Torque is better as well out to 5K rpm. Out past 5K rpm, I need to do more testing to figure out what is working best.
Yea, the car was very sensitive to knock with more advance. The result map made the most power with no knock. I layered dyno charts of multiple MIVEC maps... first with flat 0's, then 14.4's, then 28.8's to get the end result
Last edited by recompile; Jun 30, 2009 at 06:48 PM.
You can run a little more timing with less MIVEC once the turbo is lit off. It really is cam and combo dependent though. I can tell with S2s it seems tapering it off and adding the timing in is better than something like Cosworths that need to be kept advanced for awhile to keep them making torque.
aaron
aaron
I'm using the FP actuator too, which I think usually brings the tq in later, maybe around 5500 rpm with peak load around 280
Last edited by SWOLN; Jul 1, 2009 at 12:02 PM.
need a little advice on my mivec map from the more experienced...I'm running Kelford 264's on the stock turbo with meth at 29psi. So far with the help of a fellow evoM member this is what I've come up with:
From what I have gathered, tapering the timing as it approaches peak tq is best and also in the high rpm area.
If anyone else running the Kelford 264's with stock turbo is willing to share their map that would be great.
From what I have gathered, tapering the timing as it approaches peak tq is best and also in the high rpm area.
If anyone else running the Kelford 264's with stock turbo is willing to share their map that would be great.
Registered User
Joined: Nov 2007
Posts: 1,507
Likes: 2
From: Trinidad
mivec tuning is really ur setup.
i recently had Johnbradley's map on my car, off boost drivability - the car was awesome!
i was able to push a lot more timing.
then i switched to another map and had to pull timing but the car felt good. the car feel lazy off boost though.
i am currently trying different Mivec maps - but no dyno
NOTE: these were on stock cams and stock turbo.
i think i am gonna work on developing one for a off and on boost i will keep u guys posted. for now i would love some member feedback on what to look for.
i recently had Johnbradley's map on my car, off boost drivability - the car was awesome!
i was able to push a lot more timing.
then i switched to another map and had to pull timing but the car felt good. the car feel lazy off boost though.
i am currently trying different Mivec maps - but no dyno
NOTE: these were on stock cams and stock turbo.
i think i am gonna work on developing one for a off and on boost i will keep u guys posted. for now i would love some member feedback on what to look for.
Well I've seen a couple maps floating around the place, I was thinking about trying the one that JohnBradley did for the cosworth's from an old thread: https://www.evolutionm.net/forums/ec...orth-cams.html, but then I've been hearing about the map that he did for the S1's (which I think is a closer comparison to the 264 Kelfords) when he was on stock turbo, but I can't find it anywhere...anyone have a link to it?
Evolving Member
Joined: Jun 2007
Posts: 156
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From: NorCal
This may be a noob question but after reading this tremendously long thread I'm still not sure.
Would it be a bad idea to zero out the mivec map, tune everything else (boost, AFR, Timing) and then come back and perfect/finalize the tune by tuning the mivec map? Thanks for any suggestions/comments.
Would it be a bad idea to zero out the mivec map, tune everything else (boost, AFR, Timing) and then come back and perfect/finalize the tune by tuning the mivec map? Thanks for any suggestions/comments.
This may be a noob question but after reading this tremendously long thread I'm still not sure.
Would it be a bad idea to zero out the mivec map, tune everything else (boost, AFR, Timing) and then come back and perfect/finalize the tune by tuning the mivec map? Thanks for any suggestions/comments.
Would it be a bad idea to zero out the mivec map, tune everything else (boost, AFR, Timing) and then come back and perfect/finalize the tune by tuning the mivec map? Thanks for any suggestions/comments.
Evolving Member
Joined: Jun 2007
Posts: 156
Likes: 0
From: NorCal
EvoM Guru
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From: Tri-Cities, WA // Portland, OR
2) Tune AFR, timing, and boost.
3) Try a variation on the MIVEC map.
4) Check/reset AFR, timing, and boost.
5) Check for power increase/decrease.
6) Loop back to #3 until you have what you want.
In my experience, there's not that much to be had in tweaking the MIVEC map. Its worth tuning it, but don't expect to gain 20 whp unless you start with a really lame MIVEC map. More common gains are in the range of 5-10 whp.