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SUPRA ULTIMATE B58 JB4 GUIDE AND LOG REVIEW (V1)

ArthurWick

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correct, drop duty 2500 and 3000 by 5 and try again. Not sure if the little closure at 4500 is duty related or you hit a bump. confirm with another log

duty5500 to 55 too. Try to get ecu_psi to be about 1-1.5 psi below dme_bt entire pull
Ok thanks, will do! On my logs, is ecu_psi another name for ecu boost? And is dme_bt another name for ecu_target?

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Hey guys, awesome thread. I've read the entire thing, but now that I have the JB4 installed and got a log collected, it's a lot of info to decipher. I'd appreciate some help.

Some background:
  • '24 auto.
  • AA high flow cat, otherwise stock.
  • 3K ft above sea level.
  • 91 octane, it's the max we have here.
  • Map 1.
Here's my log. I started at 2.5K RPM in 3rd gear and ran it to redline. After slowing down, I ran it through 3rd and 4th gears. On the first run, there was a blip in throttle at 3.6K RPM. On the second run, there was a major throttle closure at 3.5K RPM, I definitely felt that while driving.

I'm using the duty bias settings from the 1st page. FF at 40.

duty_15duty_20duty_25duty_30duty_35duty_40duty_45duty_50duty_55duty_60duty_65duty_70
323232323536394855576262

Any thoughts on what to change to improve the throttle closure at 3.5K RPM? Is the ignition timing OK? It's hard to tell what's good and what's not for timing without having a Y-axis to look at in the pics on the first page.
 

vlad

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I changed duty_35 and duty_40 and collected another log. One small throttle closure on this run so better than before, not sure if timing is OK. Is map 1 just too much for my fuel?


duty_15duty_20duty_25duty_30duty_35duty_40duty_45duty_50duty_55duty_60duty_65duty_70
323232323232394855576262
 
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JTIGNOR

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I changed duty_35 and duty_40 and collected another log. One small throttle closure on this run so better than before, not sure if timing is OK. Is map 1 just too much for my fuel?


duty_15duty_20duty_25duty_30duty_35duty_40duty_45duty_50duty_55duty_60duty_65duty_70
323232323232394855576262
I would try to get some better fuel or some additive. I had the same timing if not worse on "94 octane". I switched to shell and got some octane booster and it cleaned my timing right up.

https://datazap.me/u/jtignor/93-booster-map1?log=0&data=1-11-26-27-28-29
 

vlad

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JTIGNOR

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I wonder if I just got some shit gas. Here’s a log on map 0. Seems like the timing is still pretty bad. I had just filled up at Chevron this morning, I’ll try Shell next time.
From what I've been told Shell is the most consistent, Id give that a try on map 1 again.
 
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ColonelAdama

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I wonyyder if I just got some shit gas. Here’s a log on map 0. Seems like the timing is still pretty bad. I had just filled up at Chevron this morning, I’ll try Shyeah ell next time.
yeah, try a different station. should be good to go when you have better fuel. Of course any ethanol or octane booster would help too, or even WMI for that matter.
 
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ColonelAdama

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ColonelAdama

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Some throttle cut is always necessary since it's trying to spool up as quickly as possible and then "catch" the overboost. The other option (making the WGDC overly conservative, but keeping the throttle fully open the entire time) would almost certainly result in a slower spool.

This was a common "dumb" strategy in the old electronic boost controller days and why ball-and-spring manual boost controllers would spool up quicker
 
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ColonelAdama

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Sweet sounds good! If I was gonna set up map 6 to run more boost than map 2 how would you recommend I do that and is that advisable? Thank you
if you are on E20-E25


map6_15map6_20map6_25map6_30map6_35map6_40map6_45map6_50map6_55map6_60map6_65map6_70
33333.544.55554.54
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