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SUPRA ULTIMATE B58 JB4 GUIDE AND LOG REVIEW (V1)

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ColonelAdama

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Just noticed this, I don't think the logged IAT is the charge pipe temp. This should be in the ~300 degF range under boost, due to the thermodynamic work done by the compressor.
Yep you are right, IAT is measured off the TMAP sensor which is post intercooler:
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Based on this info above which was my settings being an MT on V24. I haven't updated mine in a bit. If i update the jb4, is there anything i need to adjust? Is it worth updating at all?
If your car already runs well, don't bother but I have found V28+ is a bit easier to tune if starting from scratch.
 

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Moderate amount of timing corrections on map 2. Map 1 has fewer but nothing to be alarmed about. Keep it on map 1. No need for a map 6 tune.

Boost control is decent, but i see you're essentially outrunning the turbo above 5500 rpm. I would bump up duty bias for all points above 5000 by about 5 or so, and relog in 4th gear.
 

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Moderate amount of timing corrections on map 2. Map 1 has fewer but nothing to be alarmed about. Keep it on map 1. No need for a map 6 tune.

Boost control is decent, but i see you're essentially outrunning the turbo above 5500 rpm. I would bump up duty bias for all points above 5000 by about 5 or so, and relog in 4th gear.
Thank you for the response and tips! For adjusting the duty bias, I go to the “duty” tab and change the values from 0 to 5 on 5k and up?
Also what would it take for me to run map 2 safely? Do I need to add octane booster? Or maybe better quality fuel from a different gas station?
 

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The cheapest most accessible way would be to add a few gallons of E85. Start with 2 gallons per tank and we can go from there. Timing should clean up but your fuel trims will increase. Increase boost until timing starts to dip.

Next tank, add a little more E85 and we add a little bit more boost and keep an eye on fuel trims and timing. Rinse and repeat until trims hit 40, then stop.
 

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The cheapest most accessible way would be to add a few gallons of E85. Start with 2 gallons per tank and we can go from there. Timing should clean up but your fuel trims will increase. Increase boost until timing starts to dip.

Next tank, add a little more E85 and we add a little bit more boost and keep an eye on fuel trims and timing. Rinse and repeat until trims hit 40, then stop.
Ohh okay thanks, what about for adjusting the duty values above 5k rpm? Change the values from 0 to 5? Or use a different number?
 

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The cheapest most accessible way would be to add a few gallons of E85. Start with 2 gallons per tank and we can go from there. Timing should clean up but your fuel trims will increase. Increase boost until timing starts to dip.

Next tank, add a little more E85 and we add a little bit more boost and keep an eye on fuel trims and timing. Rinse and repeat until trims hit 40, then stop.
My fault I I figured it out, I changed the values from 50 - 55 in the duty page from 5k and up and this is the new data log for map 1 in 4th gear.

https://datazap.me/u/mark-gorospe-jr/log-1768993189?log=0&data=1-4
 
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Timing is good but for MT cars on stock downpipe, FF is best set between 25-35. Try 30 to start. Remember it saves per map, so you must be in the intended map before changing it.

watch Throttle. Should rarely intervene .
Thank you! Also I forgot to mention that last run was on a catless downpipe should I adjust the values that you gave me?
 
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Thank you! Also I forgot to mention that last run was on a catless downpipe should I adjust the values that you gave me?
Try 30 first but most likely with catless it will end up being 10-15. Use the recommended duty bias in the first post as well.
 

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Try 30 first but most likely with catless it will end up being 10-15. Use the recommended duty bias in the first post as well.
Okay sounds good thank you! I’ll do some more tests tonight. Does the lower number in the duty bias mean that the wategate is open for longer or shorter period of time?
 
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Okay sounds good thank you! I’ll do some more tests tonight. Does the lower number in the duty bias mean that the wategate is open for longer or shorter period of time?
Wastegate duty cycle is lower. So more exhaust gas is bypassing the turbo, therefore less boost made.
 

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Wastegate duty cycle is lower. So more exhaust gas is bypassing the turbo, therefore less boost made.
Gotcha, made those changes to the FF and to the duty bias according to the first post

couple of the first pull the traction was on
Did 1 with map 2 just to feel the difference, I feel like the car isn’t pulling as hard as it was before the duty bias adjustment, but if this is safer then that’s okay

https://datazap.me/u/mark-gorospe-jr/log-1769036091?log=0&data=1-4
 

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Try 30 first but most likely with catless it will end up being 10-15. Use the recommended duty bias in the first post as well.
Alright I’m running the recommended duty bias and have my FF at 22, highest FF with minimal throttle closure. Did runs in map 1,2,3 with the same settings. (Might have to adjust my duty30). My timing looks about the same across the different maps (I’m not sure if that’s a good or bad thing), please advise me on what more I can do to fine tune and which maps are “safe” according to my data log. (Map 3 was just a for fun run lol, I heard it isn’t safe)

https://datazap.me/u/mark-gorospe-jr/forum-baseline-22-ff-map-123?log=0&data=1-4
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