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About Jonofmac

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  1. Lol yeah. When it's a large portion of your career, hard not to be. Misinformation is frustrating and helps no one. Sent from my SM-N960U using Tapatalk
  2. Fair. I think the biggest difference you notice between the two is the 10 speed. Muuuuch shorter 1st gear ratio, really allows these things to move out from a dig pretty well. I'm coming from a 4 speed 4L80 in my cammed, head swapped, and stalled LQ4 in a 2003 2500HD lol. This 6.2 walks it from a dig (when it hooks, or if I use 4wd to launch). From a roll, I still think the 6.2 is faster The 2500 was a heavy girl, i got it across the scales and it weighed 6340 lbs and was making ~500 HP (crank, no idea what wheel was) over the stock 300 HP it made. I think my favorite thing about the 6.2 over the 5.3 when I was driving both was the torque at low RPMs. It would just effortlessly accelerate while maintaining low RPMs. Again, I'm coming from a stalled truck (3200 rpm stall), so when I was accelerating at all, i'd be at 4k rpm minimum. Perhaps it's a matter of perspective for me haha
  3. Sorry I haven't been able to work on this much recently, weather has not been cooperating. I finally got around to making the DIY video on how to remove the front grill.
  4. Since there is no DIY for this, I decided to take a few video clips as I was figuring it out during my Denali grill to a glossy black piece swap to make a DIY. Excuse the stuttering, I hadn't eaten all day and had tried several different things. I recorded after I had figured out how to remove everything. It's honestly not that bad, but you'll want 2 people when removing the fog lights and reinstalling that piece because if you're not careful, they'll fall out and scratch your lower bumper! Steps: 1) Pop hood and remove the hood release handle (2x T15 screws). Once screws are removed, handle slides towards front of vehicle and off. 2) Remove 10 plastic push clips along the perimeter of the big plastic cover. Lift straight up when done and plastic piece comes out. 3) For both fender wells, you need to remove the 2x torx screws just on the inside of the fender. 4) With your hand on the front-most bottom part of the fender flare, pull straight out to the side to release the clips. There is a 7 mm screw under the fender flare you need to gain access to. I ended up removing the entire fender flare and then removing the push clips individually, reinstalling them into the fender flair, and then install the fender flair as one piece on re-assembly. 5) Once the 2 torx screws and 1 7mm screw under the fender flare are removed, pull straight out to the side at the corner where the quarter panel meets the front lower bumper/fog light area. It *should* just pop out with some force. One of my sides gave me trouble and I had to use a plastic pick (to avoid damaging paint) to push on the pin to release it once I got it out enough. You then pull along the headlights. The piece in the middle of the fog lights will pop right out if you pull towards the front of the vehicle, or use a plastic pry tool. You MUST undo the fog light connectors from the fog light housing and remove the harness clips from the housing as well. I believe there is only a connector to disconnect on the passenger side but a harness holder/clip and the connector on the driver side. 6) To release the clips connecting this bumper plastic piece to the grill, you'll have to crawl under the truck and pull back the soft plastic cover that you'll see. You can stick a hand in there and release the locking tabs while having a helper support the plastic bumper piece and work together to remove it. The entire piece will come out this way. Note there are 3 plastic clips that hold the plastic in the bumper that will come out with a little force. 7) Remove the 3 (10 mm) bolts on the bottom of the grill that are now exposed. There are 4 (10 mm) bolts on the top of the grill that need to be removed as well. 8 ) You can either release the 3 locking metal clips (left, center and right sides) that hold the bumper in place now or later. I didn't notice a big difference. If you do it now, give a firm and quick jolt towards the front of the vehicle and you'll hear the clip release. Don't pull too far or you could break clips. 9) Grabbing the top of the grill, lift up (not too much force) while pulling towards the front of the vehicle. You have to lift the bumper a little bit before it'll come forward. 10) If you have a camera, undo the 2 (T25) screws holding the camera onto teh grill and then the bumper should be free. Installation is the reverse of removal. Best of luck!
  5. Your statement would be true except for one major thing: Transmission gearing. The 5.3 winds gears out a bit more for the same acceleration of the 6.2 since the 6.2 makes more torque. The power to the wheels is the same to accelerate both vehicles, but the power produced at the engine will not necessarily be the same. Sent from my SM-N960U using Tapatalk
  6. I'll admit I gun mine at a lot at lights. Maybe not full wot but enough to get it to shift around 4k rpm. It's just how I drive drive I've been accustomed to more power than necessary. I give the truck more gas since I'm used to the ease of acceleration that a 650 HP vette gives you, so I end up pushing the truck more to keep up with leisure acceleration in my Vette lol Sent from my SM-N960U using Tapatalk
  7. Nice. So you're now resorting to personal insults instead of showing any data. I provided a snippet of how a piezoelectric knock sensor works because you were confused. I corrected your claims, buddy lol. My ego suffers no bruises from your unsubstantiated claims or personal insults. I actually am an electrical engineer with both hardware and software experience for embedded devices and frequently work with several large OEMs (I do more than just automotive). To correct you trying to put words in my mouth, I never said it will anticipate knock before it can happen. I'm saying knock is not a binary yes there is knock/no there is not knock entity. I'm saying that you can measure the relative combustion volume/knock level and see if you're on the threshold before you get to full blown pinging. No, you won't exactly how far from knocking you are, just that you're at seeing higher combustion pressure rises. You act like the only vibrations that occur in an engine are knock. You clearly lack the understanding of what knock is and what is causing this vibration. I explained it once but I guess it didn't stick... To try to dumb it down more: as fuel gets ignited, pressure in cylinder rises quickly and this force pushes down on piston. This pressure profile varies greatly depending on when the fuel mixture is ignited (amongst other things). Too late, make reduced torque. Too early, peak pressure occurs as piston still going up (also results in negative work/reduced torque). These vibrations from combustion are ALWAYS PRESENT, but to varying levels depending on when ignition occurs and charge density. Yes, I completely agree that knock sensors cannot see the future. I never claimed they could. They must measure things that already happened. What you repeatedly fail to comprehend is that these vibrations that they see exist in every combustion cycle, regardless of whether knock is happening or not. The relative magnitude of these vibrations are what change as rapid cylinder pressures increase. ECUs sample this analog current/voltage. Misfire detection wouldn't be possible if they saw 0 vibrations except when knock occured. Don't believe me? Go hop on HPT or EFI live and change your knock sensor sensitivity to make it sensitive. You'll get "knock" reported under light throttle. The reverse is true too Sent from my SM-N960U using Tapatalk
  8. Oh my God. Yes. Excuse me for giving a simplified explanation for those that don't have degrees in electrical and computer engineering. First, it's called a piezoelectric crystal, not a piezocrystal. Yes, it's not a literal microphone, but it behaves in a similar manner, which is (to simplify it) convert combustion noise into an electrical current which can be sampled by a MCU's ADC. That vibration they detect is always present, not just during knock. Combustion is noisy. Have you personally tuned a knock ****** system? Because unless you have, you have nothing to stand on other than your (lack of) "knowledge". I know how these systems work and have worked with them with several large OEMs. Knock is not a binary thing, despite what you think. There is not only a pinging that the ECU detects. The piezoelectric crystal characteristics are tuned for a resonant frequency to make actual knock frequencies more sensitive than combustion noise (glorified band pass filter). Since knock is not a simple YES/NO, they actually can (and DO) estimate how close to knocking you are. The "noise" from knock, is a result of peak cylinder pressure happening too early, and creates a non smooth pressure waveform vs time (if you plot cylinder pressure through the cycle). This jagged edge of pressure creates the pinging you hear, however the knock sensors are sensitive enough to pick up smaller magnitudes of this and even the absence of knock (misfire detection, anyone?). They have several different thresholds uses to determine when knock has happened, which vary per RPM, and load, and even cylinder which are uses to determine the relative "volume" of the combustion. This is not up for debate, this is quite simply how the systems work. It is NOT just responding to knock which has already occured, if that were true, misfire detection would not work). I even attached some literature for you to show I'm not talking out of my ass. Yes, it is tuned to detect knock frequencies (that's the goal of a knock sensor), but they measure the knock level. Note that knock level is merely an amplitude of combustion noise for a given frequency, and this can range from none to full on audible pinging. I don't care how you think these systems work, dude. Thank you for providing literally 0 explanation to how you think the systems work and proving you don't actually know. Go back to buying canned tunes. Please don't spread misinformation. Sent from my SM-N960U using Tapatalk
  9. As a note: premium is not required. Look in your user manual and it says 93 recommended. Fuel octane rating down to 87 can be used with decreased performance. Straight out of the manual. Be careful saying it's required I agree with your notes about the 6.2 and 5.3. I noticed it a lot during the test drive. 6.2 has fantastic passing power, even when towing my 6k trailer I can pass effortlessly. Sent from my SM-N960U using Tapatalk
  10. I would argue that it still is quite relevant. The L86 vs L87 are virtually identical outside of DFM vs AFM from every piece of data I can find. Same bore, stroke, compression ratio, HP and torque. The introduction of the more advanced variant of AFM (which is DFM in 2019), won't affect any WOT measurements. The only thing it could affect is part throttle might see less of a difference than the AFM models. DFM is an evolution of AFM, where the engine has 17 different modes instead of the 2 in AFM (V8 vs V4). DFM can run on a number of cylinders ranging from 2 to 8 cylinders instead of 4 or 8. It also rotates the combustion between used and unused cylinders to help with uneven wear. That was the only "significant" change of L86 to L87. I could find all this with a quick Google across a few different websites and looking at GM's tech specs. The larger MPG drop of the AFM vehicles was due to the engine having to run in V8 mode more than it was with premium gas. DFM now allows you to run on modes between V4 and V8 modes. So perhaps a V6 mode would help decrease the gap between premium and regular gas mileage, further. This is only a hypothesis, but seeing as how AAA recorded V4 mide was activated less, it would seem possible that mpg could be improved if you could take advantage of a V6 mode instead of running V8 full time. It should not affect any other aspect of the test, considering nothing really was changed except for cylinder deactivation modes regarding the engine change. Of course, another change is 10 speed vs 8 speed. I'm not sure how that would affect gas mileage, but if the AFM model had to downshift out of 8th to cruise (I didn't see any mention of that for the flat grade testing, which is where the engine uses V4 mode, and the largest mpg difference was observed). I can't imagine having additional gears between the 8th double OD and OD could hurt gas mileage, either. Sent from my SM-N960U using Tapatalk
  11. It is NOT required as people seem to think. It's recommended (as your image shows) to achieve maximum power and fuel economy but runs just fine with regular (for those that say premium is required, read the text note. Says "fuel down to 87 may be used"). I'll post this extremely in depth ~70 page research paper from AAA conducting testing on multiple vehicles that recommend or require premium to see what the effects are. They actually say that they recommend running regular in the 6.2 because the mpg increase does not offset the fuel cost. They state that power reduction was ~2% or less on their dyno testing and fuel economy was most affected on flat ground. They observed 0 pinging or knock issues on regular because the ECU was able to switch to a lower octane table. Everyone saying the 6.2 requires premium is wrong. GM recommends premium. It was likely done to increase mpg number because they get dinged on fleet average mpg. So it's in their interest to tell us to use premium if it increases mpg 1-2 mpg, because their fleet average goes up, even though it's cheaper $/mi to run regular with slightly lower MPG. Their only metric is mpg for fleet average mpg. There are NO issues with running regular gas in the 6.2, despite what ill-informed people seem to think and say with 0 data or facts. Yes, your mpg will be affected slightly. Yes, your power will be affected slightly. Data shows 0-13% reduction in MPG (depends on driving conditions as shown by my below link), and power is down ~1-2% at > 4k rpm (no change below 4k). If you don't rev your truck much, you don't even lose HP! I'll post this research link again.... I personally run 93 in my 6.2, but gas is cheap. My old truck needed premium (heavily modified 2500) and got 10 mpg. So doubling my mpg is awesome for me anyway. https://newsroom.aaa.com/wp-content/uploads/2017/12/Premium-Fuel-Phase-II-Research-Report-FINAL-2.pd Sent from my SM-N960U using Tapatalk
  12. Tbh I'd rather have e85. My boosted cars LOOVVEEE it. My NA car is 11.5:1 with port injection and picks up a bit of power too. Gas mileage I don't particularly care about. Everything I own is in the teens or barely hitting 20. my truck is my most efficient vehicle haha Sent from my SM-N960U using Tapatalk
  13. Of course it varies per vehicle. Some systems are more advanced than others. The AAA research article noted that there was no pinging recorded on any of their test vehicles except for the Audi. They were extremely thorough with all of their testing (it's a 70ish page document). Their data shows that for the 6.2, there was no pinging running 87. The only noticable difference was a fuel mileage decrease on flat roads (due to not using DFM as much on regular) and a 2% power loss above 4k rpm. They tested driving in 0, 2%, 4%, and 6% grades. I don't know if you've been on a 6% grade, but it's pretty significant load on the engine, and no pinging was observed. GM likely recommends premium so that their published mpg average is higher and peak HP is a bit better. This makes their product look more competitive and raises their fleet average mpg (an important metric according to the EPA). It's up to you to run whatever you want. I, personally, run premium. All my other vehicles require premium (not recommended, but required) so I'm used to using it. I used it in my old truck (heads, cammed, stalled, built trans 2500 LQ4 that I built), and this truck gets double the gas mileage, so I don't mind. Maybe when gas gets expensive again, I might consider regular. But right now, who cares. I'm just saying that extensive 3rd party research was done on the 6.2, and it appears that the only ill effect is a reduction in MPG. Sent from my SM-N960U using Tapatalk
  14. Indeed is a good bump for just fuel. Nuts! Shame they didn't support flex on the 6.2. Weird thing is it has an ethanol content sensor it looks like (my 6.2 reports having an ethanol sensor and shows the ethanol content). Not sure if it's just fixed in the tune to always report ~10%. I don't have ethanol to try it with. The 6.2 would definitely benefit from ethanol seeing as it's higher compression than the 5.3 and the 5.3 picks up ~30 HP from ethanol... Sent from my SM-N960U using Tapatalk
  15. Yeah we've confirmed the payload stuff. The website I was using apparently has incorrect info. When you refer to the trailering guide, you can see this difference. Edmunds should update. Your power figures are incorrect. Not sure where you got those 5.3 numbers, but GM does not advertise it that high. However if they did have a unit that was making that power, it would explain the unusually fast 0-60 time for the 5.3 that CnD reported. I found the car and driver article. Something seems off there to me. Must be some difference in vehicles outside of just drivetrain. Every other article and independently posted number I found (CnD was one of the last for me to find, granted, I was looking at Sierra's, not Silverados), and the gap was larger. I saw the numbers I stated. Another comparison between the same truck configuration (crew cab vs crew cab) with engine swaps was at elevation, showed a 0-60 of 7.7 compared to 9.2 sec. I could not find a single reference anywhere else that showed a stock 5.3 setup getting low 6s. Absolute fastest I found was a 6.4, but with a negative DA (equivalent of being below sea level, due to low altitude and cold weather). Not sure what CnD did there, but they got much lower than average 0-60 than everyone else for the 5.3 and a tad slower than average for the 6.2 compared to other outlets. Sent from my SM-N960U using Tapatalk
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