Every car is different, so it's hard to say what is causing the sensitivity. 91 octane for sure is part of the problem, but it could be a combination of the intake and stock cat, with the exhaust you have. It could be any number of things, spark plugs, plug age, gap, etc. Do you fill up with 91 until the pump shuts off, or do you only put 5-6 gallons in at a time? If someone only puts a half tank or so in every time at the gas station, the fuel will never be a full 91 octane unless they make sure the person before them pumped 91 too. Your car likes about 3-4* less up top than most 8th gens that I have worked on. Again, a lot of tuners seem to say that "most" cars should be able to handle a certain number for ignition so they run that same ignition on all cars they tune, whether it shows knock or not. Whether that is right or wrong in practice, that isn't for me to decide I guess.
You have done a lot of detail work like porting the manifold and the TB swap. But the TB swap is only proven to add a couple hp if that on a FBO car (
https://www.youtube.com/watch?v=nygSNSHsN0E). With you having the stock cat, I don't know if that would go up or down. How much is the port work worth, we don't know either. Until you get the OEM cat removed, the car will most likely have trouble picking up power. Couple that with 100* intake temps and 91 octane and there is only so much to be gained. IMO
A fairly respected theory is for every tenth you can shave off the 60ft time is worth 2-3 tenths at the quarter mile. So everything you can do to get your 60ft time lower will help it on the top end. If you can get your 60ft time down time 2.24 like in the last video I attach below, you could be running a 14.7 or so. You can't rely on launch control to make your launches for you. Try to launch the car without launch control to find the RPM that your setup likes, then set the launch control to that and see if it works. Launch control with a super sticky tire is what makes for the ideal scenario. Very few cars on a stock street 215 tire will just dump the clutch; stick and move out like our minds think it should. On a 215 street tire at 35psi you are going to have to drive it off the line somewhat to get it moving quickly.
Some quick comparisons below...
14.41 @ 96.78,
14.34 @ 96.84,
14.21 @ 97.34 in January on 235-40-17 tires. I will assume this was done in cooler weather since it was posted in January of this year and he states 93 octane in the description. At the 2:50 mark he launches the car pretty hard, is yours leaving like this? Are your tires near 235-40-17? This guy is only six tenths faster than you with full 3" exhaust and the 3" Berk test pipe with no cat, and a 235 tire all in cooler temps. The RDX injectors are irrelevant as they don't add power, just allow you to make more power with the required mods.
https://www.youtube.com/watch?v=OR76ONZE0hs
-Hondata Flashpro 93 Octane Street Tune
-3” SSRD intake with Velocity Stack
-J35 Throttle Body
-RDX Injectors
-K-Tuned 3” exhaust
-Berk Test Pipe
-Boomba Torque Mounts
-R1 Concepts Drilled and Slotted Rotors
-Kendra Kaiser KR20A 235/40/17
-Avid1 AV-38 17x8 +38
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13.93 @ 102. Spare tire and seats removed, Michelin Pilot Sports at 25psi. FBO car with an EM1 CMC and HR shifter/cables. Posted in February, cooler temps would be assumed. You might hit this SpecTuning guy up for a tune, he street tuned his. If you're willing to pull your seats out and your spare tire, run a quarter tank of gas, run a race header and delete the cat, 3" exhaust and Michelin Super Sport 225 tires we can get you here, which is only one second faster than your current time. Well 1.1 seconds if we're being specific, haha.
https://www.youtube.com/watch?v=IMmyJDx5wKw
2010 FG2 Civic Si, stock K20z3 engine & trans, (seats & spare tire removed - 2,875lbs with driver)
- Hybrid Racing intake, shifter cables and shifter assembly
- Skunk 2 Alpha Header
- 3" exhaust, XLR8 Performance (76mm)
- RRC Throttle Body + spacer (same size as a J35)
- Koni Yellow/Nuespeed Sport suspension setup, 24mm Progressive rear sway
- Flashpro, street-tuned by SpecTuning, 220whp (
https://www.youtube.com/watch?v=PsaSH8vJSBM)
- Michelin Pilot Super Sports, 225/45/17 @ 25psi on Knockoff wheel$.
- Em1 CMC.
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14.7 @ 95mph. K-Tuned CAI and FlashPro posted in October 2018, again cooler temps would be assumed. Weather history shows a low of 62* on this day and a high of 81* (
https://www.accuweather.com/en/us/atlan ... ?year=2020). You ran a 15.08 at 94.27 in 120* intake temps at the start and 100* at the end of the track. Does he have 93 octane, I don't know, again I would assume in Atlanta they have 93. Google search shows they do, so who knows.
https://www.youtube.com/watch?v=c11VuX4UeWA
-K-Tuned CAI
-FlashPro (Unknown calibration)
-17x9 wheels (Would assume wider than stock 215??)
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14.95 @ 93.24 with a 2.24 60ft with an HR only and FlashPro. Looks like an area with 93 octane, though I don't know what the guy is running obviously. You have more mph than he does at the quarter mile, so there is a lack of getting off the line from looking at the timeslips, but you come on stronger at the top end. Your best 60ft time is a 2.411 compared to his 2.24
https://www.youtube.com/watch?v=xYSl7Wx63IE
-HR CAI
-FlashPro (Unknown calibration)
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The local legend Tong Man, 2600 lbs (
https://www.youtube.com/watch?v=3UFxXq4ahUs) full bolt on has a lot of videos showing his stages. Not sure exactly when he went 2600lbs in his car, but look through his videos here and see how they compare to your car
https://www.youtube.com/c/TheTongMan/search?query=fg2 . Lot's of FBO videos of him going 14.0 ish and he can drive pretty good. He went to no lift shift when it was available, so not sure if he has any NA videos with no lift shift before he went boosted.
Based on the video evidence I don't know which route to go in order to help you achieve your goals. As I see it, your car runs the same MPH as a guy running a 14.7 @ 95mph with 93 octane and cooler weather. So it seems the power is there based on how people determine your quarter mile and trap speed. You might hit up a forum or facebook favorite tuner and have them tune it for you. That might yield you the best results, in theory anyways. Or hit up the SpecTuning guy in the second video and see if he tunes for people, he appears to be local since the video is at Sac Raceway or Tong Man. If you want to tune it for the track, we can play with some timing and what not. But again, I need to know what level of knock you are okay with so we can get to that and not go over it. We can also add what I would consider too much cam angle on the high cam and see if that picks up for you too. My tuning style is for the street and what the car wants. The fact that you can make those runs and not have any knock is my main focus. But we can play with the timing if you'd like, there will most likely be some knock, to which we need to know how much knock is too much for your comfort is all.
My honest recommendation would be to wait until the hot months are over and then go out and try to shoot for fast times. Unless you're a boosted guy running an air to water intercooler with ice in the tank, very few people are out trying to set personal bests in July in California. :) I'd love to help you reach your goals, as unhappy "customers" like yourself cause me to feel like I've let you down. Whatever I can do to help you let me know, but it seems finding a better launch solution seems to be where we are losing time, which I hate saying because you then think I am saying it's all your fault, which i'm not. Just saying maybe it's a combo of tires, pressure, and finding the right launch rpm and clutch slipping to get it out of the hole. Here is how Tong Man does his, not sure you do it the same or not, but it's an idea
https://www.youtube.com/watch?v=B0tirCGstI0.