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topfuelman
June 7th, 2008, 07:16 AM
Tried to do a driving log and managed to collect some data. Not really sure what I'm doing right or wrong.
I know the car is mostly running rich but I am not sure where/what to tackle in the tune.

I am attaching the log and the tune that is in the car.
This is a tune that was provided to me as a starting point for my combination, but was not expected to be correct as is.

Engine has ITB's, and is running SD. 383 c.i LS1 stroker, manual.
altitude up here is about 4500 ft above sea level. The car has race cats, and full dual 3" - 2.5" exhaust.

I have not touched the tune file that was provided to me, other than I scaled the injectors flow table to what I thought was correct for my 42lb delphi injectors running at 58psi fuel rail pressure.

Can anyone offer any advice for the me to give to the fellow that will be helping me tune this on a Mustang load dyno.

Thanks,

T

joecar
June 7th, 2008, 08:53 PM
Also log the following:
MAP (kPA)
KR
IAT
ECT
VSS
DYNCYLAIR_DMA
DYNAIR


You have to keep the channel count below 25 (at the bottom of the PIDs tab)...

Drop the following:
MAP Sensor (V)
LONGFTAVG
MAPBOOST_DMA
MANVAC

You're running in OL, so drop these:
LONGFT1
LONGFT2
SHRTFT1
SHRTFT2

Are you running a MAF sensor...? If so, the log MAF (g/s) also.

topfuelman
June 8th, 2008, 04:42 AM
Okay,

I did my best to log what you requested.
Am not running a maf.

log attached.

Thanks for any insight that can be provided.

Trev

joecar
June 8th, 2008, 11:49 AM
Trev,

Add these PIDs:
TP
IBPW1
IBPW1
INJDC1
INJDC2 (these last two don't use any channels)

Do you have a wideband...? If you run in OL and/or SD you really need one.

cme265
June 8th, 2008, 12:46 PM
Trev,

Add these PIDs:
TP
IBPW1
IBPW1
INJDC1
INJDC2 (these last two don't use any channels)

Do you have a wideband...? If you run in OL and/or SD you really need one.

ditto, get a wide band o2, just might be your new best friend:cheers:

topfuelman
June 9th, 2008, 04:20 AM
After a few hours on the dyno, the tune is working much better.
We are however having some difficulty with the sensitive transition in fueling with the slightest cracking of the throttle. My excellent local tuner could explain it better, but it is something to do with the map signal and the huge change in airflow that happens very quickly when slightly cracking the throttle.

Can these areas of fueling be adjusted in higher resolution to overcome this?
Apparently with ITB's and weaker vaccuum signals, this is a common tuning difficulty.

Please feel free to throw your thoughts in here!

Trev

joecar
June 9th, 2008, 06:02 AM
I think that GMPX is working on finding the transient fueling table and add it to the tune file definitions for some tunes.

Questions:
- did your tuner adjust the injector flowrate table...?
- did he adjust your VE and/or MAF tables...?
- did he adjust the OL AFR and PE AFR tables...?

If it's ok, post some logs (I don't think he would mind logs, but I think he will mind the tune).

topfuelman
June 9th, 2008, 12:22 PM
Not sure what you mean by GMPX, but I will drive and log the car again tomorrow and post the log when I have it.
I'll add the other channels that you mentioned earlier.

Sorry, I am not sure what the tuner adjusted, as we did about 4 hours on the dyno.
I know he is now doing some further research on tuning ITB's with a fairly weak vacuum signal, and that we are going to have another session next weekend.


Trev


I think that GMPX is working on finding the transient fueling table and add it to the tune file definitions for some tunes.

Questions:
- did your tuner adjust the injector flowrate table...?
- did he adjust your VE and/or MAF tables...?
- did he adjust the OL AFR and PE AFR tables...?

If it's ok, post some logs (I don't think he would mind logs, but I think he will mind the tune).

5.7ute
June 9th, 2008, 12:49 PM
Since you are running the COS5 you should be able to utilise the alpha n (TPS VE Table) to aid in the tuning of this set up. This table was designed for the ITB or large cam engines with a weak map signal like you have.
If you log the GM.VETABLE_DMA pid once your main VE table is dialled in it will give you a starting point to tune this table.
Take a look here http://forum.efilive.com/showthread.php?t=2599 You will have to skip forwarda bit but it explains the process better than I could.

joecar
June 9th, 2008, 01:55 PM
Mick (5.7ute) is right, the TPS VE table is just for you... :cheers:

Ross (username GMPX) is one of the two EFILive people... he is the one who makes the calibration definitions for each OS;
the other person is Paul (Blacky), he writes the user software and FlashScan firmware.

topfuelman
June 9th, 2008, 03:18 PM
Awesome! My tuner had mentioned trying the alpha n table at the end of our session, so I think he is on the right track. I will pass your comments directly on to him and hopefully he can get this beast dialed in for me.

You guys are brilliant in my books. This stuff is a bit too complex for the way my brain is wired.

Cheers,

T


Since you are running the COS5 you should be able to utilise the alpha n (TPS VE Table) to aid in the tuning of this set up. This table was designed for the ITB or large cam engines with a weak map signal like you have.
If you log the GM.VETABLE_DMA pid once your main VE table is dialled in it will give you a starting point to tune this table.
Take a look here http://forum.efilive.com/showthread.php?t=2599 You will have to skip forwarda bit but it explains the process better than I could.

5.7ute
June 9th, 2008, 04:12 PM
Steve (Oztrack) & Dan (Delco) have both tuned these ITB engines successfully. Hopefully one or both of them can chime in with a few tips to help get this set up for you.

joecar
June 9th, 2008, 04:19 PM
There's more info on the TPS VE table in the COS5 thread (it's a pretty long read tho... 25 pages worth): showthread.php?t=2599 (http://forum.efilive.com/showthread.php?t=2599)

topfuelman
June 10th, 2008, 03:30 PM
Skimmed and summarized the relevant info and comments from this 25 page thread on using this feature.

I believe this will be the cure we've been searching for.

Can't wait for the next tuning session on the Mustang dyno this coming weekend.

I'vel attached a Rich text format document summary (brief) in case anyone else finds this info useful.

Thanks for the awesome input!

T:grin:


There's more info on the TPS VE table in the COS5 thread (it's a pretty long read tho... 25 pages worth): showthread.php?t=2599 (http://forum.efilive.com/showthread.php?t=2599)

topfuelman
June 11th, 2008, 02:19 PM
Say, My tuner thinks I may have screwed up my Map sensor as in his own words

" with large changes in airflow from about 40% throttle to 100% throttle there is no change in MAP signal. I understand the difference between static and dynamic pressure, but not of this magnitude. "

Does this sound like a MAP sensor issue?

I did accidently wire it up wrong and ran the car a few times before we determined there was no map signal. We rewired it and were then able to generate signal voltage values but perhaps not the full range the sensor was designed to deliver (due to the miswire???)

Here is the type of set-up I am working with. raw, and an installation shot win the chassis. There is a small volume plenum in the valley of the manifold casting for a map sensor and for brake booster vacuum source etc.

I've gone ahead and ordered a new MAP sensor to replace it, as it is 9 years old anyways.

T

joecar
June 11th, 2008, 03:40 PM
Test your MAP sensor using a MityVac style hand vacuum pump, observe the MAP pid on the scantool as you apply vacuum.

Yeah, if it's old replace it.

Double check your wiring.

Nice manifold...:cheers: