SUPRA ULTIMATE B58 JB4 GUIDE AND LOG REVIEW (V1)

[vlad]

@vlad for map1 log, the huge throttle is traction control kicking in. You can tell it's TC when you see a massive throttle cut (OEM strategy to control boost, TC, etc) along with sudden drop of ignition from all cylinders. You should consider adding some Ethanol as your timing is marginally acceptable. Pretty much the reason why map1 is the limit of 91oct, especially pump piss 91ACN

I'm 90% sure I had TC off for all of my data logs. I have noticed that ignition timing drops around 3-3.5K RPM pretty consistently. That's around the same RPM where I see throttle cuts, though the throttle cuts seem less consistent than the timing drops.

One thing I've noticed is that timing seems sensitive to IATs. I live in the high desert at 3K feet above sea level, and we have a 20-30F degree swing in just one day. So, the time of day I collect the data log probably makes a big difference. I thought I had a bad tank of gas from Chevron, since I was seeing low timing even on map 0, but then I collected another data log on a different day on the same tank of gas, where I was seeing lower IATs, and timing looks much better on map 0.

9/28 map 0 log with low timing, Chevron map 0
10/5 log - first run on Chevron map 0, second run on Shell map 0, third and fourth runs on Shell map 1.

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[vlad]

That is correct, catless downpipe will cause the DME to use thottle closure as a tuning knob on a jb4-less car. By adjusting with wastegate signal on a jb4, you are cleaning up the behavior from stock.

If you leave the EWG unadjusted, will it hurt anything? Not any worse than a dinantronix / racechip / jb-plus. All of those adjust boost sensor signal without wastegate control, and thus they will all trigger closures on catless cars. You just don't know it because none of them offer OBD logging. Side note the dinan unit will get RPM from the cam sensor, so at least you won't get "implausible pressure" errors at idle

I was thinking that maybe the AA high flow cat was making the throttle closures worse on map 0. It's not catless, but it does trip the CEL if I'm shifting around 3K RPM a few minutes after starting the car. Seems that if I shift around 2-2.5K RPM, then no CEL. Once the car has been running for about 10 minutes, I can rev it however high with no CEL.

 

[i3igpete]

Catted downpipe will trigger closures, but not nearly as much. Thats why there are separate "starter" settings in the OP.

My guess is the CEL is unrelated to JB4, but rather the O2 sensor heating up either too fast or slow with the AA.

 

[vlad]

Catted downpipe will trigger closures, but not nearly as much. Thats why there are separate "starter" settings in the OP.

My guess is the CEL is unrelated to JB4, but rather the O2 sensor heating up either too fast or slow with the AA.

Oh yeah, the CEL is from the cat, not JB4. I was just saying that even though there is a cat, maybe its impact on boost control is closer to catless than to stock.

 

[i3igpete]

It's effect is about half. Thats why Adam recommends changing FF from 50 to 40 with catted, rather than 30 with catless.

 

[razorlab]

For reference, here is the ignition retard table the DME uses during intervention based on TC and/or tire slip. It's a bit aggressive for the S58/B58. It's one of the first things I fine tune on track tunes.

 

[ColonelAdama]

I'm 90% sure I had TC off for all of my data logs. I have noticed that ignition timing drops around 3-3.5K RPM pretty consistently. That's around the same RPM where I see throttle cuts, though the throttle cuts seem less consistent than the timing drops.

One thing I've noticed is that timing seems sensitive to IATs. I live in the high desert at 3K feet above sea level, and we have a 20-30F degree swing in just one day. So, the time of day I collect the data log probably makes a big difference. I thought I had a bad tank of gas from Chevron, since I was seeing low timing even on map 0, but then I collected another data log on a different day on the same tank of gas, where I was seeing lower IATs, and timing looks much better on map 0.

9/28 map 0 log with low timing, Chevron map 0
10/5 log - first run on Chevron map 0, second run on Shell map 0, third and fourth runs on Shell map 1.

yeah I mean your timing isn't even great on map 0, would recommend finding a way to boost octane, or you could maybe try IAT spoofing at 120-130 to bring down timing some to get fewer corrections.

The closures aren't bad enough to worry about for now.

 

[vlad]

OK, I gave in and went to the one gas station in town with E85. I got 2.5 gallons of E85 and the rest 91 octane. Log here. Does it look OK? I see that trim is around 45 around 3K RPM but then drops at higher RPM. Should I try map 2, or will that be too much?

 

[vlad]

I switched to map 2 and did a couple runs - log here. Trim is pretty high and there was a major throttle cut around 3.5-3.7K RPM on both runs. Looks like boost and trim were way too high there. Too much E? Or maybe the car behaves differently at 3K ft above sea level?

Here's the map 1 log again from yesterday. Same tank of fuel - 2.5 gallons of E85, the rest is 91 octane which I'm assuming is E10, though there was no sticker on the pump explicitly saying that. If so, then online calculators say this is E24.

Same duty bias and FF settings on both map 1 and 2.

FF at 40.

duty_15	duty_20	duty_25	duty_30	duty_35	duty_40	duty_45	duty_50	duty_55	duty_60	duty_65	duty_70
32	32	32	32	32	32	39	48	55	57	62	62

If the goal is to keep trim below 45, then seems that map 1 is already maxed out up to about 3.5K RPM. Looks like there's room for more boost than map 1 at 5-6K RPM? Based on the two logs above, how does this look for a map 6?

map6_15	map6_20	map6_25	map6_30	map6_35	map6_40	map6_45	map6_50	map6_55	map6_60	map6_65	map6_70
2.2​	2.2​	2.5​	2.5​	2.7​	3​	3​	3.5​	3.3​	3​	2.5​	2.5​

 

[ColonelAdama]

I switched to map 2 and did a couple runs - log here. Trim is pretty high and there was a major throttle cut around 3.5-3.7K RPM on both runs. Looks like boost and trim were way too high there. Too much E? Or maybe the car behaves differently at 3K ft above sea level?

Here's the map 1 log again from yesterday. Same tank of fuel - 2.5 gallons of E85, the rest is 91 octane which I'm assuming is E10, though there was no sticker on the pump explicitly saying that. If so, then online calculators say this is E24.

Same duty bias and FF settings on both map 1 and 2.

FF at 40.

duty_15	duty_20	duty_25	duty_30	duty_35	duty_40	duty_45	duty_50	duty_55	duty_60	duty_65	duty_70
32	32	32	32	32	32	39	48	55	57	62	62

If the goal is to keep trim below 45, then seems that map 1 is already maxed out up to about 3.5K RPM. Looks like there's room for more boost than map 1 at 5-6K RPM? Based on the two logs above, how does this look for a map 6?

map6_15	map6_20	map6_25	map6_30	map6_35	map6_40	map6_45	map6_50	map6_55	map6_60	map6_65	map6_70
2.2​	2.2​	2.5​	2.5​	2.7​	3​	3​	3.5​	3.3​	3​	2.5​	2.5​

yup that map 6 should fix it

 

[FLtrackdays]

I’m going way back on this thread/post. I filled up at a gas station while on vacation that sold E85. Could we run our cars on that by itself or is it always a mixture of E85 that you have to run? It’d so simple to just fill up and go on E85 alone and tune the JB4 for it, if that’s even possible. I can’t remember exactly but it said one hundred and sumthun octane. So out of curiosity I read somewhere it’s not only more power but cleaner and cooler to run as well. What’s your thoughts on doing just that?

Side note, I woulda hit you up while in Greenville, SC but we only stopped by for the night on the way to Asheville, NC. When I have more time, TBR and meeting up with the Colonel are on my bucket lists.

 

[ColonelAdama]

I’m going way back on this thread/post. I filled up at a gas station while on vacation that sold E85. Could we run our cars on that by itself or is it always a mixture of E85 that you have to run? It’d so simple to just fill up and go on E85 alone and tune the JB4 for it, if that’s even possible. I can’t remember exactly but it said one hundred and sumthun octane. So out of curiosity I read somewhere it’s not only more power but cleaner and cooler to run as well. What’s your thoughts on doing just that?

Side note, I woulda hit you up while in Greenville, SC but we only stopped by for the night on the way to Asheville, NC. When I have more time, TBR and meeting up with the Colonel are on my bucket lists.

Nah Full e85 is not possible with locked ecu, stock flash. it will run too lean. Start with only 2 gallons E85 in the tank, it doesn't take a lot to make a big difference.

 

[GRMan]

Nah Full e85 is not possible with locked ecu, stock flash. it will run too lean. Start with only 2 gallons E85 in the tank, it doesn't take a lot to make a big difference.

Any news on the possible adaptive boost feature that you were mentioning previously?

 

[ColonelAdama]

Any news on the possible adaptive boost feature that you were mentioning previously?

I haven't heard anything yet!

 

[ColonelAdama]

You guys are gonna get some more BEF content soon, DME going across the pond this week.

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