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Discussion Starter · #1 ·
Just a question on ignition advance.. Cars been mapped by RB Motorsport and runs absolutlet fine, but i do like to tinker a bit and belive that lots of time can be spent fine tweaking the map after a professional tune.

Soooooo...

On my power FC i have adavnced the ignition by the ign/inj setting (Rod sensible locked out he full map!!!:D ) by a couple of degress and using the map tracer to see at what load sites i might get a knock warning (engine light set to flash at 30 knock). Drove home tonight watching it and throughout the first 4 quadrants on the map i.e. upperleft 2x2 square there was no hit on knock.

Is there much benefit to be had either performance/response/economy wise by playing with ignition timing in this and possibly other areas of the map?? Can you go to far with ignition advance without getting knock in these load areas what would happen?

Dont worry wont be doing this and using fullboost & fullthrottle !
 

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To be honest if your car has been mapped by RB Motorsport I can hardly think of anything in your map that you not being a Pro could be able to improve.

Just leave it as is and enjoy driving it. :)
 

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Discussion Starter · #3 ·
Yup i know Rods maps are very good so your right..

just that i didnt think a tuner would spend the few hours for mapping optimising a map at the lower load sites and would probably more concentrate on the more critical areas of the map. Im bit like Kismetcapitan and cant help tweaking stuff!!
 

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i think your right chaz i believe higher ignition at lower load can increase fuel economy and power coming on boost and even bring it in earlier, i cant speak for rb motorsport but i think that alot of tuners do as you say concentrate on the fueling for higher boost as this is where you see the effects more obvioulsy, i would guess that a tuners own car would have alot more hours spent mapping on the road and on the dyno to create that perfect map, whereas we the paying customer are constricted but how much time is avaliable and the cost
 

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much of my mapping does indeed include that "off-boost" quadrant, and you can enormously influence drivability by changing both the ignition and fueling.

The trick however, is that you are off-boost. At WOT and boosting, ignition mapping is rather straightforward - as much advance as she'll take without knocking. But when puttering around, one needs to think more like a N/A tuner would, and in mapping non-turbo engines, more isn't always better. It's very much hit-or-miss and a very tedious trial and error process. I mostly focused on the 3000rpm range because I hate turbo shuffle (who doesn't??) and it can be cleanly mapped out if both ignition timing is optimized, and the fueling is just right. With fueling, you have your zones where you're shooting for economy, your full-boost zones where you dare not run too lean (yet too rich saps power), and the in-between parts, where you can directly control the nature of your torque curve by manipulating the fuel map.

Save your original map!! Then you can start fiddling - 2~3 degrees at most, and it will keep you entertained for a loooong time! Setting my full boost map didn't take long. Tweaking the spool-up part of the map for fastest turbo spool took a bit longer, and there is an overlap zone between the WOT diagonal, and fast highway cruise (say, 100~120mph and 0.3~0.7 bars boost continuous), where I had to compromise the fueling from max torque to eliminate shuffle.

But street driving and the 1500-3500rpm range, can be fiddled with endlessly. When it's right, the car is snappy, almost as if it's a V-8. Then the season changes and it all goes to pot and you've got to start over again :p (there are temperature compensation tables but they are far from precise - if you are picky about performance, one really does require 2~3 maps and switch between them throughout the year based on average ambient air temps, plus humidity can noticeably affect things by acting as an anti-knock agent, yet displacing oxygen in your intake charge.

It's definitely true: a tuner can't spend 15-20 hours on the road (no traffic required) to fine tune a map....or one could, but surely that's going to cost a lot of money! But the first quadrant is a good place to get a feel for mapping - the upper right-hand quadrant rarely gets used except on overrun, and high-load low-rpm doesn't get used either - my FC Edit logs have never touched that zone. I suppose I ought to tow a boat if I want to dial in that section!

And it goes on and on :)
 

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I am sure Rod has put a "safe" map in it, timing and fuel wise. Same as Nissan and other makers do with stock ECU's. If you like to live dangerously then I am sure you might sharpen things up with some more advance and a bit less fuel at some points. As an old tuner I used to know had on a sign above thousands of pounds worth of dead engine internals nailed to the wall, "Speed costs money, ultimate speed costs LOTS of money, how fast can YOU afford to go....?". I'd leave it alone unless you don't mind risking a bit of det and buying Rod another bike or other new toy :) Is it running closed loop off boost? If so the O2 sensors should give a pretty good cruise mixture.
 

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Discussion Starter · #7 ·
Thanks for the responses guys, all interesting. Given that Rod has locked the map out (cos he knows what im like lol :D ). I cant play too much but can at least try a couple of degrees of timing and mod the fuelling whilst in the safe low load, low rpm areas of the map.

Chris - probs already paid a big chunk off Rods mortgage with a very nice engine rebuild so know where ya coming from!. I've actually turned off the 02 feedback control to get bit more economy as Rod has purposely made it lean at tottering / cruising speeds maybe 15-16:1.

Kismet- dont have the ability to do the full on fettling that you seem to love !!! but much appreciated for the info. What would happen if i put say something ridiculous like 10° advance in the low load areas guess you might not get knock but maybe stall the engine as the ignition would be way to late to transfer power efficiently to the piston?
 
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