MS First start

DemonGT

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Finished up my Pimpxs install and got the car fired up for the first time tonight. Started right up no issues and seemed to idle ok but has a surge.

Was wondering if someone could glance at my data log. I let the car idle and come up to temp.

looking at the tables for fuel and timing im not sure what i should be looking for to make improvements?
 
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a91what

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Some questions for you.

Are you running boost? how much?
COMP ratio? what heads?
What fuel?
Cam?
I see alot I would alter off the bat but each engine is a bit different.
 
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DemonGT

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No boost, staying N/A
about 10.5 to 1
Running Victor Jr heads
running 91 pump gas
Cam is a custom cam, i can get any specs you need just dont know them off the top of my head.
I gave the duration info to Stinger when i ordered the Pimp so not sure if that matters with the base
tune sent if its just a "generic" one for most applications to get you started or if its more personalized.

I watched your video for setting the timing off set and got it so my timing light shows 20 on the balancer
to match the black box in TS, but im concerned the timing is not right. I may have mentioned this in another thread
but years ago i removed my timing cover and when i did that i had to remove my adjustable pointer and i never marked its location before removing, so im not sure that matters in TS as long as the pointer is reading the same as what's in TS? Raising the timing when fixed did not see to raise up my idle, and it would only allow me to go down to 16?

I know i still need to do some work on the timing/fuel table. Do you recommends using the WUE auto function?

the AFR should be 14.7 but it was running around 13.3 or 13.5ish? So i need to take the numbers in the fuel VE down?
 

a91what

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First thing I would do is rescale the VE table for an NA application.. the tune they sent is scaled for 30psi and is using up alot of the fuel table resolution

The timing map should be ok to get you going for now. The AFR table is set to be rich at idle... you may want to rescale and alter the AFR table as well.. I could do all of this for you. or let you do it and tell you what to change

if you cannot lower the timing below 16* then you need to take a look at the IGN offset, it should be 10*
 
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DemonGT

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If you could tell me so i could try on my own that would be great. I really wanna learn and i feel doing it myself will help.

Where do i find the IGN offset?

Cam duration @ .050 intake 240 exhaust 246

the VE tables should only go to 100 instead of 300?
 

DemonGT

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Another thing i noticed is i have a 180 thermostat and in TS it was reading 173 when up to temp? Does the sensor need to be
calibrated or is it normal for it to read a bit off?
 

a91what

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You should have gone through and done a full sensor calibration before beginning any tuning. Its normal for a sensor to read slightly askew due to the nature of thermistors
 

DemonGT

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Went back and reread my instruction from Stinger and made some changes.

Did a little tuning tonight. Had a surging idle and was running rich. I adjusted the AFR table in the idle area leaner and turned the
fuel in the fuel VE down and it smoothed right out. The fuel cells in the idle area were in the 40's and i had to go down to 27
for the AFR to get to 14.5 and the idle to smooth out. I did a quick 5min log of the idle. 14.7 is normal for NA engine what is considered
to lean? Also, for close loop idle should i be using MAT or CLT?

Car still skinks like hell though lol
 

a91what

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CL idle you can use either, I make the rpm columns all one number anyway so it wont matter. 14.7 is stoic and is considered a complete burn of fuel in the cylinder. you can safely lean the engine out to 15.3ish or as lean as it will allow before it begins to missfire and otherwise complain. I personally just target 14.7 because I run cats
 
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DemonGT

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If i set the AFR in the idle cells it does not seem to change the AFR unless i change the same cells in the fuel ve? Im not understanding what is being looked at to get to the target AFR? If i have to manually change the fuel to get to my desired AFR what is the AFR table doing?
 

a91what

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It depends on how you have the tune setup.. did you select "incorporate afr" under general settings? You should, it takes the afr table into account.
The ve table has to be tuned no matter how you have the tune setup, that's what sets the main fuel. The AFR table is what the autotune will use to reach target. It is also used for ego control. Once the car is tuned you can then simply alter the afr table and it will affect the main fuel.
 
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DemonGT

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I will definitely check that out. I just thought it was odd that the AFR was set to 14.7 in the cells it was idling but my afr would not change
unless i adjusted the fuel ve table down. I figured the afr table was used for the autotune portion but was unsure how the afr was maintained during idle or
when not using autotune? I was under the impression autotune was not to be used during idle?

Once the tune is to a point your happy with do you continue using autotune when you drive or no?
 

a91what

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Autotune helps YOU dial in the ve table.. it gets things very close and then you can fine tune things and do some transitional blending.
Once the ve table is tuned and you have ego setup correctly then your "done" there are many other tables that need tuning but those are best done with datalogs over the course of a few months... that is if your looking for an oem quality tune
 
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a91what

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idle- with sequential injection - 14.4-14.9 ; batch fire - 13.5-14.7 depending on cam
cruise- 14.5-15
WOT- depends on the build.. NA 12.5-13 ; boosted 11.5-12.2 depending on boost level and if your cooling the piston with fuel.

these are generally acceptable ranges broadly speaking
 
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DemonGT

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When looking at a table when driving or revving the cells climb from left to right. I was wondering what would cause a engine
to be at a higher rpm, but a low kpa or %baro or a high kpa/baro at lower rpm? If everything is running correct it does not seem like
you would ever get into those cells?
 

a91what

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sometimes you wont.. low rpm and high KPA bins, high rpm and low kpa bins are typically never touched. I simply fill these areas in with values that make sense based on the VE trend.
You can plot the usable ve area in a map using the histograms in MLVHD
 
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DemonGT

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Well, after the car sitting all winter i decided to stop being lazy and get it up and running again and maybe do my first auto tune drive.

I completely forgot about datalogging, i was guessing it would not start after sitting but to my surprise it actually started right up and idle was pretty good. I
watched the closed loop idle curve and everything seemed ok and doing as it should. After the engine was up to temp it started to stubble and i noticed my AFR was going lean. The engine died and only then did i think of the datalogging.

I started a data log after checking for anything noticeable under hood and restarted the engine and it started and idled for a short time before doing the same.
Not sure if this is a tune issue or mechanical. I replaced the tank, pump and level sender about a year ago.

FYI after the second time it died i could not get the motor to run again, It would turn over and fire but not run.

attached are current tune and the short log i did after the first time it died. I have a second log i did after it died the second time of trying to start it
iv attached also.
 

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