More Timing than High Oct table

[Kfred 513]

I'm wondering why my car is seeing more timing than the High Octane table is commanding. I have checked out all the tables on the spark advance tab and nothing seems to be set in a way that would add spark. Anyone with more experience have any input on this? Take a look at the quick 2-3 pull around 14 minutes in my log. The most obvious section is above .80 airmass and above 4800rpm. The car goes pig rich because it was the first test hit with Meth spraying, I am already massaging the VE table for that.

Also, i am on the 2 BAR OS.
2 BAR OS 1.7 smothed VE table after good AFR.hpthome.hpl

[DHC]

Take a peek at your PE/COT table

Why 2bar?

[Kfred 513]

Take a peek at your PE/COT table

Why 2bar?

Thank you Sir! That looks like my exact problem. How do most people modify this table? I would guess either leave it alone, or zero the entire table. Since i have changed the parameters for my car entering PE, seems like the timing corrections in this table may not meet the intent of the oem calibrator anymore. All Zeros might be the way to go.

I switched to 2 bar for a few reasons. I was chasing my tail on the VVE. Adjusting 5-6 cells resulted in 20+ being altered by coefficient calc. I spent a lot of time reading about changing the boundaries, and played with the bluecat tool a bit as well. Mainly i switched for a normal VE table. I have also been running the car in open loop SD only for at least 6 months. I have been told that the car only references the low octane table with the MAF failed. I recently added an Alky Control kit, and I want an ultra conservative Low Octane Table to help save the engine if the meth system ever fails in any way...seems like that isnt a possibility with the MAF failed. If i am wrong, please correct me.

[DHC]

I zero that table as I set my timing after my PE set. Sometimes I will change PE to get a couple more degrees of timing or lean it out at the top to bring in a little more HP. I do make sure the ECT and IAT tables are active. More heat should pull timing. The low octane table MAF only thing is new to me, maybe some else can chime in and confirm or deny.

I understand the struggle.

I have great success running blended but in the end most end up MAF mostly, I do build a proper VVE table as that affects transients and some other calcs. I tune the MAF perfect and timing table together, while building my MAF curve I start to rough in the VVE table. Lots of things affect my decision on where to set the RPM for high speed mode. Big cam cars I will use the VVE tables at and around idle and bring the MAF in once the airflow straightens out based on RPM. Small cams and blower cars most of the time end up with high speed mode all the time. Turbo cars get the SD only program as I have yet to get a MAF to work clean and smooth. If the MAF airflow and hertz readings are erratic than a airflow straightener works like a charm. When it comes to timing tables I always copy my High table into my Low table and remove 4 degrees while tuning and usually pull 2 more when complete. I feel that is enough buffer room for bad gas. Obviously watching my commanded table and cross referencing to make sure I am getting what I am asking for when I ask for it, just like you did in this post.

In my opinion the virtual tables are nothing more than a visual representation of the math and formulas. Sure we can data log it and apply error math and filters, but in the end it is not absolute and will change day to day, hence fuel trims and the factory getting away with the terrible stock VVE tables.

I have my opinions on how and why I do things and some may not agree and that is fine. With that said I am all ears for proven theories with proper data to back it up and I am not big headed enough to listen and try all ideas.

Why the Alky Control kit? Do plan on putting boost to this? What are the big plans for the car? Sorry for the questions just trying to understand thought process.

I am not familiar with alky use on NA motors, but am with boosted stuff. I honestly wont touch a alky car. My belief is that if the car needs a supplement, then other means need to be looked at to achieve end goal. Bigger injectors, bigger displacement, more boost, piston oil squirters, less compression, plug gap change, etc...

Hopefully this kind of makes sense

[Kfred 513]

Check this thread of mine where TCSS07 mentions it in post #4. He is sharp and was spot on with my issue. https://forum.hptuners.com/showthrea...d-Engine-Power

I decided on the alky control kit as a means to give the car more octane. I live in Vegas where 91oct is all i can get at a regular station, and E85 stations are limited. I spent a long time debating E85 or Meth and went with the meth for versatility. Im in the military and may end up someplace without Ethanol in a couple years, I have no way of knowing. I tuned my old 4G63 car on E, and it just proved to be a nuisance and I was always worried about it sitting too long and sticking an injector shut, even though that many people have good luck.

My car, as you saw, is only running 17-18 peak timing. That is where I have to keep it to avoid any KR. Most LS7 guys can run 25*, and my cam should allow that. I blame low octane, and milled heads giving me mid 11:1 static compression. Since it is a street car, running race gas all the time is not on the table. The meth is no doubt a variable that is hard to nail down. Even with the progressive controler, the technology is a bit archaic. With all that said, in my case meth seems like the best way to go, and if it doesnt help me, ill just turn it off and save the pump for when i eventually go FI.

My car trapped 117 with the cam, but before the headers and meth, I'm curious to see how it does once i get the tune straightened out.

[DHC]

I did read that thread a while back, and again just now. I think your thinking on the low octane and MAF only is wrong and in that thread post 4 he said "since your still on a 1 bar os and in ve mode your spark will default to the low octane chart so you must copy your high octane over to the low octane to get the proper spark" That I agree with, SD in stock OS does revert to low octane table. Just wanted to clarify.

Got it and understood on your thinking about the alky. It is kinda weird the motor picks up KR any higher than it does. Even with comp ratio bump I would think 93 non-e should get at least 20-22.

If it were me I would revert back to stock OS, dial the MAF, VVE and Timing and call it. With the KR I would make sure fueling is on point and get timing to no KR. Then fill tank to 3/4 add a can of Boostane and add 4 from .7 down and blend up from there. Hammer it and see. Dyno would help, but not always viable. I have one and use it to rough in part throttle and dial idle and WOT fueling and timing. When done then to the street for drivability and final polish on fueling and timing. Then back to the dyno for power pulls and timing/PE changes for max effort tunes. Most of the time if I question KR is real or not Boostane, fresh fuel and re-test.

I am not saying what you are doing is wrong because in the end you did what you wanted and as long as the car puts a smile on your face, the rest doesn't matter.

Hopefully that table I showed you gets you to your target.

[TCSS07]

kfred513 - if your looking into bumping up your octane some more look into boostane - its a good product that works and will bump your octane numbers and pretty affordable if you didnt want methanol
what DHC said above - didnt read 100% through

[Kfred 513]

DHC I did a poor job explaining, but yes, I meant the stock OS uses the low octane table when in SD only. That is another big reason I switched to the 2 Bar since I have been SD only for about 6 months now. I have also been in open loop because after the headers i just couldnt get my NBO2s to cycle properly. End game I would like to switch back to CL operation, but the car just didnt run smooth. the sensors would stop cycling during highway cruise and idle. I know the process for adjusting them after headers, I just haven't taken the time to mess with it.

I wish I could find 93 non-e, but like i said, i'm in Vegas and i only know of E10 91. A few stations sell E85 but all of them are out of the way for me, E85 just wasnt the best choice for me. I also looked into Octane boosters, and over the long run, Meth is the cheaper option by a long shot. I understand the risks, and i accept them. I'm curious why you dislike the 2 BAR OS. Seems like most people that use it advocate for it even for NA setups. I haven't been using it long enough to find any negatives, but I always like to hear others opinions, especially since you have a lot of experience.

TCSS07 I for sure looked into boostane and other octane boosters in general. At the end of the day I went with an Alky Control kit. It will be interesting to see how it performs. I agree that a good NA build on good gas wont pick up much or anything on meth. However, I believe my car really does need the octane, and my low timing numbers back that up. Once i Get it all sorted out ill have to make a pass at the track without Meth, and then flash the meth tune and run it again, let the MPH do the talking...or not?? As always, thanks for your input!

[DHC]

I live in a state that is e10 91 or 91 without so our options are extremely limited, welcome to the Big Sky. I try and tune all my cars on e10 91 as that is most available across the region. Because of the random mom and pop gas stations and crappy fuel possibilities every one of my boosted builds leave with 2 cans of boostane, just encase.

O2 Swing with headers and big cam can be a huge PITA, I get it. That part of the tune can be very hard to nail down. From what I have found if you can get the fueling within +/- 3%, minimal spark correction, BRAF within +/- 1 g/sec and the torque/throttle follower tables dialed things really smooth out. I sometimes have to go back a mess up spark control and BRAF to get the "chop" people want. Down side is drivability, some don't car about surge and buck, drives me INSANE. Because we don't have the track days like most we just tune for drivability, reliability and fun factor.

I really think you can get the max from this car with some time spent getting the little things dialed in, using what ever OS you want. Fueling and timing are easy, it is the rest that takes time to polish out.

Are you wanting a MAX effort tune for everyday? Like, be ready for any other person that wants to play/race on the road? Or good daily tune and track/race day tune?

Keep up the good work