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Thread: Tuning Help

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Posts: 1-10 of 26
2011-10-19 04:03:35
Tuning Help
Hey guys, it has been a while since I've messed with my car but now I'm back into it. I had installed a wideband while the car was sitting around (with a broken trans) and now that I have it fixed I can see that I was running decently lean. The tune I had put on there would hit mid 13's:1 so i have put it back to my old conservative tune, which actually still hits mid 12's:1 (I have a theory about this). I think that it may be hitting the mid 12's because the boost falls off rather quickly at higher RPM's (wastegate issue I believe) which changes the fuel pressure...

At any rate, I have attached my tune below (for the setup in my sig) and I want someone with some tuning experience to take a look at it. I'm getting mid 12's at cruise speed and when I step on the throttle it drops to very low 10's then slowly builds to mid 12's again. It's idling very rich as well. I know I can screw with the latency for the idle but other than that I am clueless. Any suggestions?

(This is with the B13RT w/LC .XDF)

I should also mention that it doesn't spool nearly as quickly as I think it should, with about 15-20psi at around 3500-4000rpm. I think it's just crazy rich down low and a little lean up top.
Last edited by RedDragun on 2011-10-19 at 04-07-57.
2011-10-19 04:50:06
Your K value is too high. Your fuel map values are too low, which further shows that your K value is too high.

On 520 cc injectors, and a little lean K value, my WOT Fuel map values are higher NA then yours are .

I'm attaching some OEM tunes so that you can use them as a reference .

Remember that adding a higher flowing MAF requires you raise your K value, while adding bigger injectors requires you to lower your K value. The higher the K value the richer you are, the lower the K value the leaner you are.
2011-10-19 12:47:52
After reading some of your material you have posted, you say that the Primary Fuel Map with feedback uses the O2 sensor? I don't even have mine hooked up anymore (that's where the wideband is at the moment).

So you are saying I need to richen the primary fuel map no feedback and lower the K value?

I have attached a tune that someone sent me a while back (the 17psi_293whp.bin) and one that is a combination of the one I posted earlier with the fuel maps from the .bin above and the injector voltage tweaked a little bit. This is the one that ran way too lean.

I promise I'll figure this out eventually... just wanna take baby steps so I don't have to replace an engine lol.
Last edited by Vadim on 2011-10-19 at 14-25-40. Reason: Attachments removed due to being Copyrighted
2011-10-19 15:04:28
No feedback map is the one you will mainly touch. Every part that shows 192 and above is knock sensor feedback area. If the knock sensor is not present then the 192 is read as 0. As in no additional fuel added above what the baseline is (K value controlled).

For fuel maps, when you see a value at or above 192, just take 192 and subtract it and you will get the actual value. Thus if you have a 200, then that's really an 8, and if you have 180, then it's really -12. If you look at the feedback map, you will see all of those 192's translated into a regular number.

For knock maps, it's 128 or above. Thus if you see 128 it's really 0* and 145, it's really 17* of timing.

Anyway, without an O2 sensor, you can tune your feedbacks out, or you can just remove feedback areas all together.

PS. I was notified that your bin's where copyrighted (JWT), thus I removed them.
2011-10-19 15:48:35
My bad on the .bin's, I honestly don't remember where a lot of them came from and it has been to long to remember which are copyrighted.

I will give a whirl later this evening or tomorrow and try to get the hang of it. I wish I had someone that knew this stuff that wasn't out of state!
2011-10-19 17:01:31
Originally Posted by RedDragun
My bad on the .bin's, I honestly don't remember where a lot of them came from and it has been to long to remember which are copyrighted.

No worries, I'm sure most people wont even realize what's what. I know I wouldn't have noticed it if it wasn't pointed out to me.

I personally just found an OEM bin that was made for my ECU specifically and built on that

Originally Posted by RedDragun

I will give a whirl later this evening or tomorrow and try to get the hang of it. I wish I had someone that knew this stuff that wasn't out of state!

It's a bit to learn, but really isn't hard once you get a hang of it. Just ask away and I'll do my best to reply quickly with what I know .
2011-10-21 02:45:41
Well, just got back from tooling around... The tuning trip was largely unsuccessful. My friend and I couldn't make heads or tails of what the values in fuel map actual do (or what they even represent). The scale is RPM for Throttle Position correct? We couldn't see any noticeable difference between setting all the red values in the no feedback fuel map to + or - 10. Didn't really want to mess with it much more after that lol.

EDIT: So lower the number is leaner, the higher is richer. 192=0, and above that is richening? Also, would it be beneficial to send a 14.7afr signal to my ecu from my wideband or to just dial out the feedback map?

Also, when you say to set the values so the ECU doesn't look at the feedback map, how would do that?

The red areas of the map vs. the blue areas of the map, what do those mean? I'm assuming the red areas are the ones used by the feedback map?

The end result of tonight was setting the K value to 42000 just for safety; the car now cruises at like 10.3 afr and at WOT in 1-4 gears it goes between that 11.8 or so. In fifth gear it seems to hit like 12.9 which I attribute to the load. I'm gonna post on a local forum and see if anyone around town has tuned with this before...
Last edited by RedDragun on 2011-10-21 at 03-16-07.
2011-10-21 05:06:10
RPM is for what RPM you are in. TP (Theoretical Pulsewidth) is engine load, it is not throttle position. Tuning TP out becomes tricky. You basically need to find out at what TP you are in boost, so that you can adjust your fuel and timing accordingly.

For O2 feedback to be enabled the value needs to be around 192 (yours is -12 points lower). To disable the O2 feedback (not really suggested), replace 192 with a 0, or if you have anything different then 192, like 200, take 192 and minus it from that number, in this case it would be 8. Your bin had 180's, that's negative numbers and fairly unusual. I would change all 180's to 192's.

Don't plug in your 14.7 feedback either, not yet at least. Now adjust your K value until your regular cruising AFR's are around 14.7. Then start adjusting your in load section to be rich enough, be careful it will be very lean!

Don't give up so easily. Have some confidence, people come into this thinking they can never succeed, and guess what, with that mentality they never do succeed. Gotta be open and willing to reread tuning material out there.
Last edited by Vadim on 2011-10-21 at 08-31-24.
2011-10-21 12:51:28
Not giving up, just frustrated. It's also very trick around here because the car is LOUD and finding a place to do this without upsetting law enforcement isn't easy lol.

Okay, we did set the K value to get the cruise to ~14.7, but when I pulled over and turned around, I couldn't get the thing to even move at partial throttle (no boost) it was so lean (scared me). After this we just put it to a very high K value and had fun for a bit (it spins at the top of third, I really don't know how much more power I need but I want it to run smoother and idle better).
2011-10-21 19:48:04
I hate driving my car hard right since it's na, so much louder then when it's boosted. Attracts too much attention

What wideband are you using? Also you said your running your WB instead of the Narrowband? Does that mean it's in the Jpipe?
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