rb20det diy tuner

[alexj]

thought i'd say hi

i've got a hcr32 rb20det mildly modded; 0,9bar with a big exhaust and FMIC with a self-tuned safc 2 using my innovate lm1 - current making 230bhp at the hubs.

i've got s13 370cc injectors and a rb25det turbo waiting to go on but i'm keen to replicate the safc tune i've already got with a rom edit and get everything setup right first.

anyway i've just got nistune installed - i chipped my ecu back in feb/march and have messed about with liveedit, consult and an ostrich emulator a bit. but couldn't get my head around watching the lm1/datscan map trace/liveedit all at once .... while at the same time trying not to destroy my engine.

hopefully i can make some progress now - just thought i'd run some ideas past the guys on hear see if what i'm thinking of makes sense.

so my initial plan is to turn the closed loop flag off on the cruise area of the fuel map, turn all the safc adjustments off and go out and trace afrs and adjust the k value until i start getting something like the stock theoretical afrs

question. is adjusting k the right thing here - i mostly read about adjusting k for new injectors? i know from the alpha correction that consult shows and the safc adjustments i've made that i need about 10% out of the fuel map almost everywhere to get sensible afrs - so i figured i'd adjust k to get everywhere close. is that a good plan?

pahse two is to then tweak the fuel map to get it spot on - but sure the best approach to doing this - road, track, dyno . i don't know how many load/rpm sites you get to map on the road without driving like a idiot which i'm not ...

thoughts and or advice would be great

alex

[Fusion Ed]

Hey Alex, where in London are you? anyway, sounds like your going about it the right way. Don't expect to be able to do this and drive however. You will need someone to drive for you to make a good job. If your Heathrow side of London, once you have the hang of it you could always head over to Surrey Rolling Road and tweak it there.

Ed

[alexj]

i'm in twickenham - funny you should say that, i did have surrey rolling road in mind for the on boost/ high load mapping. i'm still trying to figure out which of my friends i trust enough to drive for the road mapping ....

i'm right in thinking that for these sort of purposes i shouldn't adjust the TP scale at the same time as the k - thats only needed if change injectors?

literaly
1.turn off the safc adjustment
2.turn off the closed loop flags
3.reset the ecu (cleear the self learn)
4.hook up lambda and consult inputs
5.drive arround whilst tracing
6.teak just the k value until the trace is somewhere near the theoretical afrs for the matching cells on the factory map

doh the more i think about it the less i think i know what i'm doing lol

[Fusion Ed]

Well your not far from SRR at all! I'm Croydon way.

There is no benefit to turning off the closed loop flags, they actually help. Reset is a good idea. If you have a lambda sensor you will need it on the down pipe to get a reliable idle afr. You can get the K value pretty well just sitting still, you may need minor changes once your moving.

You sound like your doing fine.

Ed

[alexj]

i've been a bit shy with getting on to SRR to book some time - not sure how they'll take it if i phone em up and say; hey i've got some software i dont know how to use, can i come down and waste some your dyno operators time while he patiently watches me make a dogs dinner out a simple task that he's seen done properly 100 times ...

re the position of the lambda sensor - i've got a boss in the decat pipe that i have used for the 02 sensor the few times i used it - i even drilled a hole through the floor under the passenger seat so i don't have to dangle the wires through the window do you reckon putting the lambda probe in the decat pipe would do the job well enough?

i kinda of had two alternate plans; the one described above and another where you leave the closed loop switched on and adjust the k while watching the alpha aka "self learn fuel adjust" in the consult data and try and get that to 0 (not much point watching the afrs since the ecu will be trying to keep the to 14.7)

BTW really appreciate your input, i've read a fair amount about this stuff online and i'm a IT techy by trade, so its not far from my comfort zone, but you're never sure you've understood something until you can run it by some else.

[Fusion Ed]

Charlie (the guy at SRR) wont mind, hes a good chap tell him Ed from Fusion Motorsport recommended him.

Just do a couple of hours on the road with a friend to familiarise yourself. Although to be honest depending on your spec you may be ok on the road, and a rolling road is over kill. I did two pulsar GTI-Rs with nistune this afternoon, on the road no problem. Both running about 1.4 bar boost. Generally I prefer to use the r/r if cars start to exceed 400bhp or so.

You seem to have all the right ideas. I actually find the whole nistune system one of the easiest quickest mapping systems I have used.

Oh and by the way I use the method of closed loop feedback to get the K value about right then go for a drive and confirm that it collates higher up the load maps too.

[alexj]

thought you might be interested in some data logged last time i had it on the dyno - pretty much the same spec as now - only added a turbo elbow since i think. chassis dyno so power at the hubs. third gear pull

http://www.skylinegts.co.uk/alexjr32/ec ... 6abbey.GIF

the lambda probe was the dyno's not my lm1 and so an up the tail pipe job, therefore fueling isnt quite a lean as it looks but as you can see my diy safc "tune" does a reasonable job of keeping the afr level at 11.5-12 ish - so it shouldnt be too hard to replicate this with a ROM edit.

i'm hoping to get a bit more top end out of it (the peak power is at 5500 rpm or somethinge and use to be at 6500 when it just had the exhaust and none of the other mods). I can't go leaner but it maybe running out of TP scale on the ignition map and pulling timing (read that on the skylinesaustralia forum a guy called cd_drift)?