WB Maf Tuning ... Questions/Logs

[2000C-5]

Why would I go back to stock OLFA table instead of leaving it at 1.0 (14.7). It idles great from hot or cold starts???

Does it matter? It's only used in open loop anyway, right?

Okay....that makes sense....thanks.

Yea, my exhaust gets hot!!! ..... I have Titanium (Z06) catbacks and they turn PURPLE after a day at the track


DH

Cool.

...and that 0-119 in 11.26 seconds don't suck either.

[Dirty Howie]

Does it matter? It's only used in open loop anyway, right?

Thats what I'm thinking too. But since I don't really know I put it back to stock. I think it idled rougher.......I will test this at a later date....but I wanted to go back to CL finally. See next post.

...and that 0-119 in 11.26 seconds don't suck either.

Must be my tuning prowress


DH

[Dirty Howie]

Well I couldn't wait for more input before going back to ClosedLoop (are you guys on vacation or something ). I left COT disabled. I put my OLFA table back to stock (but would like input on leaving it 1.0)

I setup my histogram/config to record fuel trims and burst knock (as suggested by Russ). And there is a lot of it !!!!!!!!!! I guess burst knock is in negative degrees so but I figured out how to get it to display properly on the histogram. Still not sure which table to use to get rid of it

The log below isn't real long and the ambients are not warm (this was at nite) but I would like to hear any input. I like where my AFR is ..... a little lean at low rpm/cruise and a little rich at WOT. My fuel trims seem negative but maybe too much?????


DH

[EC_Tune]

Actually looks pretty good Howie.
The only time you get Burst KR is when you go from a low throttle to a high throttle. Just like it's supposed to work.

The Burst KR tables are on the Spark Retard Tab:
However you can reduce the effect of BK by increasing the values (Mult table by 1.5 as a good start) on the Burst Knock Enable Delta Cylinder Air Threshold vs RPM. You can also decrease the values (closer to 0 where it is negative) on the Burst Knock Retard vs Engine Run Time (ERT) vs Engine Coolant Temp (ECT)

[Dirty Howie]

Actually looks pretty good Howie.

Well thats good to hear.........

The only time you get Burst KR is when you go from a low throttle to a high throttle. Just like it's supposed to work.

The Burst KR tables are on the Spark Retard Tab:
However you can reduce the effect of BK by increasing the values (Mult table by 1.5 as a good start) on the Burst Knock Enable Delta Cylinder Air Threshold vs RPM. You can also decrease the values (closer to 0 where it is negative) on the Burst Knock Retard vs Engine Run Time (ERT) vs Engine Coolant Temp (ECT)

Thanks for spelling out which BKR tables!!!!!!!!

So I have a question: Should there be SOME BKR or is it OK to have none???


DH

[EC_Tune]

If you zero out the BKR tables and you don't get actual KR, leave em zeroed and add timing to the higher g/cyl area... LOL

[Dirty Howie]

Thanks Doug and Russ !!!!!!!!!!!

I logged on way to work first.....and had BKR of up to 7.5*(first log)

I zero'd out the two BKR tables referrenced above ... see tune below.

Then I logged on the way home from work.......and had NO BKR and NO KR (second log)

And there was NO audible ping. I still want to monitor for ping and KR/BKR in hotter temps........before I feel comfortable.

I'm "NOT A TUNER" but my fuel trim histogram looks awsome I think ??? My VE/AFR however is not to good .... should I worry about this??


DH

[EC_Tune]

Yeah, a little rich at WOT but *very safe*. Looks like working on the AFR Error% vs MAF hz at WOT should straighten things out nicely. And pick up a little power as well.

[Dirty Howie]

Yeah, a little rich at WOT but *very safe*. Looks like working on the AFR Error% vs MAF hz at WOT should straighten things out nicely. And pick up a little power as well.

I intentionally tuned the maf so AFR was rich at WOT because of the pinging I would get at ambient temps in the high 70's thru 80's.

I know I should have tuned the MAF to the commanded AFR and then used the PE table to adjust the AFR lower in the higher RPM regions. And played with some IAT tables as well but I only had a short time when the temps were in the 80's and didn't want to mess with something new. I can always go back and do it the right way once I see that these AFR's keep the ping away.

But as you say the AFR at WOT is "safe" and I might try adding some timing as you suggested.

Plus I am going to the track in a couple of weeks......do you think this tune is OK for the harsh track conditions its going to see


DH

[EC_Tune]

If it pings when ambient temps rise, I would work on the IAT spark table to take out a little mroe spark when ambient temps go up. I wouldn't necessarily add main spark.

[Dirty Howie]

If it pings when ambient temps rise, I would work on the IAT spark table to take out a little mroe spark when ambient temps go up. I wouldn't necessarily add main spark.

Thats because you know that there is such a thing as "IAT Spark Table" where as this is news to me.

Just to clearify.....I wouldn't add spark if I get ping I was going to try to add spark if I DON"T get any ping with my current settings when it gets over 80* outside......hopefully this weekend.

But I will look for the IAT Spark table and check it out....THANKS


DH

[EC_Tune]

Ugotit!
Don't forget to post your times!

[Dirty Howie]

Ugotit!
Don't forget to post your times!

Open track racing at WSIR not the drag strip. 30 minute sessions of balls to the walls. Thats why I was asking if this tune seems safe. But I will post those times if you like.....

Im bringing my MPVI for logging and possibly my laptop if I have enough time between sessions to check for KR etc. You have to drive with the windows down so you can't hear pinging @135 mph down the straight


DH

[EC_Tune]

LOL The wind noise probably drowns out a LOT of other noises. LOL
Are your current times like your sig? Or are you getting better now?

[Dirty Howie]

LOL The wind noise probably drowns out a LOT of other noises. LOL
Are your current times like your sig? Or are you getting better now?

Unfortunately my that is my best time. I usually am right at 1:40.

But now that I am tuning my car who knows

Its supposed to be a light turnout so I should get lots of clear laps (no Porches in my way )....only thing slowing me down is my BALLS

******I added 1* of timing in high MAF/RPM and turned off LTIT per your tip*******

No KR (might add another 1*) and no PING. But want to see some 80* ambients first.

Seems like it did idle better. But noticed 19+ AFR at startup.

Hope cruizing around at 15.5 AFR is Okay ...... gas prices are getting rediculous


DH

[EC_Tune]

We're getting screwed, blued, & tatooed here in CA.
Look here

[Dirty Howie]

We're getting screwed, blued, & tatooed here in CA.
Look here

Sucks !!!!!!!


DH

[NHRA-TA]

Dirty Howie how come under your name it say not a tuner?

[EC_Tune]

Special Request of the Admins...

[Dirty Howie]

Special Request of the Admins...

.....And cause I ain't


DH