I hope you can answers this.

Can a lean condition lead to knocks and spark retard?
If I get knocks in a certain rpm vs load map, should I start to lower spark advance or add fuel or both?

Does all your idle timing tuning be done in the "closed TPS spark advace vs rpm" or in the "main spark advance vs rpm" ?

I How is it with larger cams and idle, do thay need more timing to keep it idle nice?

And last:

If i add spark advance do that also lean out fuel? How do you balance that. Do you put as much advace as you can before knock then back it out, and then adjust the BLM in that area?

Thanks

 

Detonation is from the combustion chamber temps going high. Adding a little fuel or reducing the timing are cures. You have to experiment to see what your engine likes best. In tuning it's about giving the engine what it wants, not what you want to give it, and there is a difference.

Closed TPS

In general yes. The larger cam with more overlap in effect introduces it's own EGR effect at low speeds, so sometimes you need to add a little timing. But, it's easy to get carried away thinking smoother is making the engine happy.

Timing and fuel run hand in hand, you have to consider both. With time comes, getting it right quicker.

You'll see that at one time you'll be happy, but as you learn more you'll revisit things, and get them even better.

Might grab a copy of Tuning Tips from the FTP at DIY-EFI.ORG and see if that helps.

 

thanks

I got a hotcam now. WIth my stock chip the idle whas smooth. Now I have a new chip from a tuning company here In Sweden that used a wideband to set my fuel maps both cruise and WOT.
THey also did the timing, but im not happy with it. I got alot of knocks at 1300-1800 rpm @ 40-60 Kpa.
The BLMS are pretty strange, sometimes dead on, sometimes to lean or to rich. To lean when I let go of the throttel from a high rpm run. And to rich during slow acceleration. Strange.
The car goes like hell thou! The wot is dead on with the wideband.
The cars is also going lean in the same area I got my knocks.
So I will add som fuel there.

And with the new chip the idle is "hunting" when the car is cold!
I got my idle speed to 900rpm ( 6spd ). And when starting the rpm goes nice upp to around 1300rpm and then starts to drop. BUT all of sudden the rpm dropps fast to 500rpm and then upp to 1300rpm then drops...
After about 2 minuts the hunting has stopped.

My guess is, to little timing or to lean at idle. The "cool start enrichment vs coolant" kicks in first, when the rpm goes upp to 1300rpm. Then when its stops, it drops to 500 rpm and the IAC tryes to keep it from dying, and then it goes upp and down untill the engine gets hot ( after 1 minut or so ).?

And what should I look at in datamaster?
is it "LTerm-C Counts"
"LTerm Adj"
Sterm-C Counts"
??


Whats your toughts?

yes and i cleand the IAC did a minimal idel set, tps volt at 0.60

thanks