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'08 SDenali - a little tuning help from forum geniuses?

Posted: Tue Aug 05, 2008 12:33 pm
by G8RDenali
Hey Guys,

Everyone on this forum has been VERY helpful with getting me (a newbie) on track with tuning my 6.2L Sierra.

When I originally installed a tune (the 87 Octane performance tune), I had some pretty significant knock going on above 4700 RPM's. As per Mike's recommendation, I amended the tune to add +5% more fuel under WOT above 4,700 RPM's . However, I'm still getting some knock.

With the excellent help of Mike and 06MonteCarloSS, I've managed to do my first Datalog. I'm hoping to adjust my truck to do the following:
1) Eliminate the remaining Knock / pinging above 4700 RPM's
2) Get rid of the damn governor
3) Milk every last ounce of economy out of the truck while still realizing some power gains.

The truck has a Volant intake and Corsa exhaust (I heard this can make it run a bit lean). I live in Florida, so 95 degree heat and high humidity is common.

I'm going to upload the CSV, if anyone can give me a hand tuning this bad boy, I'd sure appreciate it!


EDIT NOTE: I did my log at steady cruise with the cruise control on. The problem I'm having (pinging) is at WOT, does this mean I should jam the fun pedal during my log? Should I do several full throttle accelerations in the log to get maximum data, or can you brain-iacs tell what's up with the truck simply by looking at this cruise data?




Thanks,

RE:

Posted: Tue Aug 05, 2008 8:16 pm
by ches111
First of all.. The file that you posted was the dataviewer file NOT the exported .csv file.

That is ok I was able to look at it anyways.

Your Bank 1 LTFTs are on average ~9.3 and Bank 2 are at ~8.1 on average.

So I would change the injector slope -9 and have a go at that..

Lew will probably back that up..

Hope that helps.

Remember to drive ~50 miles after the change. I would still monitor right away to make sure any changes you make were NOT fat fingered.

RE:

Posted: Tue Aug 05, 2008 10:47 pm
by 06MonteSS
yup...

haven't looked at the log, but if Ches111 did and your average ltft's were 9.3 and 8.1, then yes, go -9% on your injector slope setting...

and again, like he says, go 30-50 miles before you log again...

RE:

Posted: Tue Aug 05, 2008 11:15 pm
by ches111
Lew I am NOT a Canuck!! I am an American!! ;)

Get your NBS 07 GMC and Chevys straight would ya :)

RE:

Posted: Tue Aug 05, 2008 11:20 pm
by 06MonteSS
:lol:

wow, my bad man... sorry... just read it quick and briefly glimpsed at the pic....

I edited my post to give you credit...

:lol:

wow, I feel bad...

sorry dude... again, my bad!!


hahahaha


no harm, no foul??

:lol:

RE:

Posted: Tue Aug 05, 2008 11:23 pm
by 06MonteSS
HEY G8R, DO WHAT CHES111 SAID!!

RE:

Posted: Tue Aug 05, 2008 11:23 pm
by CANUCKPREDATOR
Absolutely there is a foul. Get your shtuff straight Chevy is the other truck. GMC only builds trucks. :)

RE:

Posted: Tue Aug 05, 2008 11:24 pm
by 06MonteSS
hahaha...

dude, I got too much shit goin on...

I know..., like I keep tellin' Mike at diablo..., gotta read ALL of the words...

:lol: :lol:

RE:

Posted: Tue Aug 05, 2008 11:25 pm
by 06MonteSS
oh shit, now THAT was Canuck!!!

WTF!!!

you guys are confusing me!!!

RE:

Posted: Tue Aug 05, 2008 11:26 pm
by 06MonteSS
I know how to tell 'em apart... Canuck is pulling his house behind his truck...

got it...

RE:

Posted: Tue Aug 05, 2008 11:33 pm
by CANUCKPREDATOR
Its so much fun messing with ya Lew!! :)

RE:

Posted: Tue Aug 05, 2008 11:41 pm
by 06MonteSS
:lol: :lol:

Re: RE:

Posted: Wed Aug 06, 2008 2:05 pm
by G8RDenali
ches111 wrote:First of all.. The file that you posted was the dataviewer file NOT the exported .csv file.

That is ok I was able to look at it anyways.

Your Bank 1 LTFTs are on average ~9.3 and Bank 2 are at ~8.1 on average.

So I would change the injector slope -9 and have a go at that..

Lew will probably back that up..

Hope that helps.

Remember to drive ~50 miles after the change. I would still monitor right away to make sure any changes you make were NOT fat fingered.

THANKS ALL!!! I'm going to give it a shot based on what you said and let you know how it comes out.

Also, I've looked everywhere, but I can't seem to find out what the hell LTFT stands for-- any help? Is there a place I can go and READ what the hell changing injector slope (and all other variables) one way or the other does?

Thanks,

Re: RE:

Posted: Wed Aug 06, 2008 2:10 pm
by mikel
06MonteSS wrote:I know how to tell 'em apart... Canuck is pulling his house behind his truck...

got it...
OK, thats funny...

Re: RE:

Posted: Wed Aug 06, 2008 2:22 pm
by 06MonteSS
G8RDenali wrote:
ches111 wrote:First of all.. The file that you posted was the dataviewer file NOT the exported .csv file.

That is ok I was able to look at it anyways.

Your Bank 1 LTFTs are on average ~9.3 and Bank 2 are at ~8.1 on average.

So I would change the injector slope -9 and have a go at that..

Lew will probably back that up..

Hope that helps.

Remember to drive ~50 miles after the change. I would still monitor right away to make sure any changes you make were NOT fat fingered.

THANKS ALL!!! I'm going to give it a shot based on what you said and let you know how it comes out.

Also, I've looked everywhere, but I can't seem to find out what the hell LTFT stands for-- any help? Is there a place I can go and READ what the hell changing injector slope (and all other variables) one way or the other does?

Thanks,
LTFT = Long Term Fuel Trim... these are a couple of the parameters you will need to log.. you will have 2 of them... Long Term Fuel Trim Bank 1 and Long Term Fuel Trim Bank 2

for info on making adjustments, read here:

http://diablosport.com/index.php?name=P ... opic&t=917


adjusting the slope negative makes it spray more fuel, so it makes you richer.

adjusting the slope positive makes it spray less fuel, so it makes you leaner.

if your average LTFT's are, for example, +6... you would adjust your slope to -6% to get them down to around 0.

if your average LTFT's are, for example, -5... you would adjust your slope to +5%...

etc etc etc...