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What is it? i was doing some adjusting on my 91tune the other night, added some spark. First one degree, logged, no ST or LT KNK RETARD. Added another degree, once again i got no ST or LT KNK RETARD, but got a couple degrees of KNK FUEL RETARD.
I could only find a couple of posts about knk fuel retard, and got conflicting info. What is this?
Fuel retard sounds to me like its pulling fuel.
 

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Discussion Starter #3
cant get my predator to work on my computer yet. computer wont recognize it. i have only been able to do the watch and record live.
 

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Maybe DiabloMike will chime in for some answers. ?
aarcuda,,, iv asked that question myself,,,, without an answer. Sure, got a list of the PID and hardly a description. (No I was directed to a site) PID list.
texaschally, I think, the Knk fuel retard is > timing pulled, beacuse of knk coming from fuel defiency. I see this fuel knk when I bang off the rev limiter,opps, I think fuel and spark shuts down, (both) on rev limiter. When fuel shuts off I get the fuel knk pid and showes pulling a deg or two.
DiabloSport, we hope will set us straight with an answer.
FT
 

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love your signature: 100% stock, then sneak in the vortech as an afterthought, for weeks I thought you had an awesome stocker
 

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KFR is a response to ST and possible LT knock. So it's confusing to me that you're seeing zero ST / LT KR and it's pulling timing in response to that. It's HAL's way of trying to protect the motor.

If you're not running 93 OCT fuel, then you need to for sure even if running the 91 OCT tune (my car preferred the 91 OCT CAI tune when I was stock and I've only run 93 oct fuel or better for the track).

The issue with your computer is you don't have the right driver for your computer to recognize the USB to Serial cable. If you search for the drivers you can usually find a free one that works. First go to DS website and go into Support / Downloads and you'll see the latest drivers there. If those don't work, then you go out on the net. The funny thing is, that's the hardest part of datalogging...once you get your laptop to recognize your Predator, the rest is pie.

HemiSam
 

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MMMMm Pie...

New question same topic... Heatsoak and ST knock? anyway to combat that? Is it something to be concerned with? I am having some STKN after the engine has been running for a few hours during a WOT burst.

Nothing too extreme, but if I can find a way to deal with it, I will be a happier guy.

To TXchally, hope you get the right drivers running, so you can get full use of it the Predator.
 

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If you frequent the DS forums, the guru's response to ST and LT KR is to throw more fuel at it. I personally didn't care for how that made the car feel and the only measure I had at the time were a bunch of 0-60 romps. It seemed I lost a few tenths getting the ST KR to zero.

When the car was stock I was basically running 93 octane fuel, the 91 OCT CAI canned tune and pulling fuel and adding timing across the rpm ranges at WOT. Worked for me but everybody's different.

HemiSam
 

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lashlarue, I was not trying to be cute. lol. Motor is 100% stock with 1 power adder. The SC. I wish I run a stock NA motor running low 12 high 11s wow it be cool.
Hemi Sam I do the same, with running the fuel octance higher than my tune setting for saftey measure and pull less timing.
OP and others, still wants to know what the Fuel KnK Retard means, and why it reacts as it does. I have been unsuscessfull at obtaining rock solid info.
No DiabloSport to help us yet with an answer.
Maybe a tuner could chime in and give a direct for sure answer.
FT
 

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FT,

I'm no expert but KNK FUEL RETARD is measured in deg (degrees). My understanding is that it's HAL's response, by pulling timing, to a measured knock issue. In other words, the knock sensors have picked up short term knock (and if over enough time that's long term knock) and HAL's pulling timing. Again, no expert but that's what it looks like to me.

I have not seen a detailed definition, just my logs and the exchanges on the DS forums, the LX forums and more limited on the Challenger forums. That's all I got to offer...

HemiSam
 

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Having a 180* stat should eliminate any heat soak problems, Sunday I made my fourth trip to HMP 1/8th track, The 1st was a baseline early in March. [email protected] Ive improved as my 60ft.s have gradually improved.Two weeks ago a 392 6-speed ran , his best a [email protected], later that day he let a friend drive it, an unexpected pro tree,caught us both off guard, but he, more than me. I ran a [email protected] he spun and simply gave up and idled down the track.Sunday I posted my best 60 ft a 2.11, and my best time [email protected], considering I forgot to turn off esp and didn't use auto stick. Duh!My R/t short shifted 1-2 at 4800, 2-3 at5400 so I had a nice long run in third and still posted a PB. Think my screw up cost me at least a tenth and 2-3 mph.The gassers outnumbered the stockers at least 10 to 1, so I was fighting the water box all evening long.My first run a [email protected] was with my worst 60 ever a 2.57. My second listed above was in the left lane where the water wasn't so bad, still had to manuever over two puddles,but staged with dry tires.Unlike HRP in Baytown where the staging lanes are long enough to drive around the water, that simply is not the case at HMP.
 

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HS Im seeing the same, as myself I log the KNK and the knk volts to each pid sensor then I go over the logs like im looking for a cure for cancer.,,, lol. I see what your saying, and understand what HAL does. Just not enough,,,,,I been looking for the answers, and have a call set up in the morning to get it explained to me. In detail.
Mention E-85 and D.S. is all over it. Look for a answer about tuning, as the O.P. is and others, something D.S. should know about and help with,,,,CRICKETS
FT
 

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Feel your pain, G. I had issues with the Trinity for a while and that was like pounding my head against the wall. Got it worked out, but it wasn't as easy as it should have been. Let us know what you learn. We could use it...

HemiSam
 

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Discussion Starter #14
@sam, im running only 93oct with the 91 tune. i wasnt showing any ST or LT knock. im thinking i was leaning out a bit, hadnt added fuel for TB. i assumed that since i wasnt getting any knock, all was good. Finishing up my exhaust and wideband install tomorrow, so i'll be able to track that AFR from now on.

I have downloaded/installed/uninstalled/reinstalled every driver diablosport has. Cant get it to work, and havent had time to mess with it since.
I need to get back on that.
 

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Yeah. The USB to Serial driver can be a giant PITA. Also, it's dependent on your operating system. If you search on google for USB to Serial drivers there are some free ones. Just look for one for your op system on the laptop and don't be pulling down from a site you don't have a thumb up on from whatever virus protection software you use (e.g. McAfee, Norton...). You'll get it. Shouldn't be that damn hard, though... I wouldn't mind DiabloSport having some real competition ;-)

HemiSam
 

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oddly enough, my diablo trinity worked with Vista and Windows 7 by the radioshack USB to serial driver for the cord I got for the Innovate LM 1 wouldnt work on windows 7. I needed a new cord and driver. its all good now
 

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I really don't understand DS's fascination with e-85, true it has an octane rating of 107, which would be a tuners wet dream, but it takes btu's of energy to create power.and e-85 falls about 30% short.Nascar is running pure ethanol but those are carburated applications where it's relatively easy to double or triple jet size in order to get the volume needed to make power.To do this in a fuel injected engine would require a huge increase in the size of the injectors and a head redesign and cam change to get the amount necessary into the combustion chamber and most likely compression ratios above 12.5 to 1. If I wanted a race engine, I would have bought something with a race engine and it certainly wouldn't weigh 4100 lbs.
 

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Last night I ran Capitol Raceway outside Washington DC. Crofton to be exact. I run a 16 challenger 6.4 scat pak. I experimented with fuel. I ran 11.995, with 93 octane without VP octane booster additive. I ran 11.904, not my best of 11.6, with the octane booster. VP is a reputable name. I mixed 1/2 quart with about 4 gals of 93 in the tank. Shook it vigorously and did the run. The better results could be, and probably are, because I raised the launch speed and the temp was a bit lower. BUT WAIT, DON'T CHANGE THAT DIAL THERE IS MORE! The real test came with data logging on the Trinity. The knock retard completely disappeared. As we all know ...the warmer it is out the worse that gets and my logs from previous days show some knock retard on stomping on it at high rpm's
usually taking from 2 to a high of 8 on 2 rare occasions. The data log graph was clean.
 
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