Pick Apart My Ign Map - Rb26 Tune

[djvoodoo]

timing should not be tapering down with increase in rpm..should do opposite.. more advance with rpm.

you may need to pipe the timing down bit to start then ramp it in.

Prior to getting it tuned I had a look at other RB maps and i was also wondering myself why the decrease. I have taken -2 deg off rows 14-15 in the 4000-6000 rpm range.

Will get the tune re-done shorlty

[Lithium]

... this is closer to being the main reason ...

I did wonder why this is? is that because the duration between each compression stroke is effectively shorter?

... than this is ....

torque drops off, less cylinder pressure so you effectively can dial in more timing

Though they both have an influence. This isn't a stab, I just think that if you are tuning your own car or dishing out advice it's worth understanding the fundamentals a bit better yourself... ponder on it. Not that I know anything, I'm one of many who have been put in their place for thinking they have a clue which might be worth sharing to help people get good results.

[djvoodoo]

I guess my next question is. Currently along rows N16-N20 in the Load areas L14/L15. Timing is already around the 20-22 degree mark. Whilst some are saying that it should increase as RPM closes out to max, I should not increase this anymore, but rather decrease along the 4000-6400 rpm band where MBT is.

Would it be a silly move to increase timing in N16-N20 even if knock stays the same? Would I see any advantage or am I already at the potential limit of this particular tune?

[Dose Pipe Sutututu]

Though they both have an influence. This isn't a stab, I just think that if you are tuning your own car or dishing out advice it's worth understanding the fundamentals a bit better yourself... ponder on it. Not that I know anything, I'm one of many who have been put in their place for thinking they have a clue which might be worth sharing to help people get good results.

Point taken on board, I actually tune my own cars and also my mate's cars. I have access to a dyno however do the bulk of my tuning on roads late at night.

However in the past instead of getting constructive criticism (which I always welcome) I get responses like "good luck blowing up your motor" OR "take it to a tuner" etc.. hence the jaded and cynically response.

If you compare us to forums like evolutionm.net where people openly share maps and talk about tuning, we are living under rocks.

[Dose Pipe Sutututu]

I guess my next question is. Currently along rows N16-N20 in the Load areas L14/L15. Timing is already around the 20-22 degree mark. Whilst some are saying that it should increase as RPM closes out to max, I should not increase this anymore, but rather decrease along the 4000-6400 rpm band where MBT is.

Look at your dyno graph and plot out where the torque peaks and beings to decay but yes you're on the right track. perhaps the range 4000 to 6400 is quite excessive, I won't tell you what exactly to do..

also keep an eye on EGTs.. don't drop timing too much

[djvoodoo]

Ok.

So assuming the Dyno run was done in 4th gear, max torque appears to be at around road speed 125-130kph, which would equate to around 4600 rpm and then starts to fall.

So assuming in this Load area, I reduce the timing to around 20deg, the remainder of the timing map should be equal to or higher than 20 deg (if knock is not reading higher, and EGT's remain the same)