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Thanks heaps for the fast responses guys

Seems odd that the old tune had soooo much more timing in it, possibly something we did wrong on the dyno?.. the torque figure seemed to be higher when getting up to the load point and then settled lower after that.

its definately on the lean side in a few areas, i would try and get them richer then see what it wants timing wise.

if the motor is the same as before switching to E85 then i would have expected it would want more timing rather than less ?

Motor is certianly unchanged, never even came out of the car.

I too expected from all my research that more timing would be required. Something isnt right here...

Is it making more power? To much timing can kill off power before any nock.

Same reference angle in the calibration? Kalmaer did have some bugs in it wonder if there was something here?

Power increase is marginal at best (5kw..)

Not sure what you mean about reference angle? Both the new and old bins are up...

Holden202T wrote:its definately on the lean side in a few areas, i would try and get them richer then see what it wants timing wise.

if the motor is the same as before switching to E85 then i would have expected it would want more timing rather than less ?

According to dynosim ethanol likes slightly less timing. Must burn faster. Anyway, timing ended up pretty bang on, make best torque at around 24 deg full noise, plateau from 22 to 26 deg. After experimenting with AFRs, V6s like 8.4 on E85.

Interestingly torque falls over a cliff after 4000rpm, its looks unnatural.

I believe the issue maybe with valve springs are weak and loosing control. There is weird noises from about 3000 rpm on heard through the knock ears.

Biggvl wrote:Power increase is marginal at best (5kw..)

Not sure what you mean about reference angle? Both the new and old bins are up...

it was 10kw

Not sure how reliable that xdf is there's some weird numbers in there, Not sure how much air flow these have at full noise but if it's anywhere around 800 the timing looks pretty expected peaking at 26 degree.

Dylan wrote:Not sure how reliable that xdf is there's some weird numbers in there, Not sure how much air flow these have at full noise but if it's anywhere around 800 the timing looks pretty expected peaking at 26 degree.

That was the max timing I tried where it was starting to go past MBT. So seems pretty good where we got.


On a side note, everything I calculated and predicted with E85 was virtually bang on. I calculated and also checked sources and got a figure of 8.4:1 at 100Kpa.

we tested the full rang and power remained stable from 8.6 to 8.2 out side of those numbers the power started to fall.

Though ethanol can take a lot more timing before it detonates, its MBT according to dyno sim is less and if that old tune was anything to go by, then yes it did require few deg less to be bang in the middle of MBT range. Also dynosim shows same engine on ethanol the torque improves at lower speeds. Also seemed to happen if the old tune was anything to go by.