[Andrew1127]

Found the limitations for the jb4 on our platform. Dialed the jb4 the best that I can. Cars will need spark plugs gapped tighter if we want to take full advantage of the jb4. Fighting a overboost issue on upshift through gear 1-2-3 and misfires during those high boost upshifts. Had to tune down the jb4 to compensate for the overboost to avoid the misfire, which takes some of the power that would be available if it didn't overboost.

I bought plugs and was going to put them in, but the ALLdata showed a 6.2hr job, and dealing with draining and filling the newer R1234yf coolant, bit much for DIY guy looking to pop a couple covers and change out plugs and it's hella pricey to get a shop that has the new machines to do it. lol I'll start a gofund me haha.

I'll attach my draggy 1/4 mile with winter tires and stock wheels.

I have my wheel swap this comming Monday for the PS4S and aftermarket wheels. I'll be sure to snag another draggy when I have those on and can get out!

 

[Andrew1127]

Sounding like spark blowout/misfires is an issue on more than just my car with the increased boost.

I have my car scheduled in for spark plug swap next week, found a shop willing to do the work that has a much lower labour cost than the dealerships. My summer tires swap got delayed, I guess they swapped out the summers for all seasons. They can't find any record of the swap except on the internal gm database, nowhere on the window stickers does it show it's been upgraded to the QBJ optional all-season tire upgrade, or any of the paperwork I signed. Sounds like they are looking to resolve the issue but we will see.

Hopefully can get tires resolved before the plugs for some dragy runs to see what the tires + lighter wheels do to improve times. If not I'll post up a draggy with the plugs and tires and hopefully blow my last draggy runs out of the water.


Edit: just got an email, they are just coordinating the arrival of the new tires, and mount + balance. Hats off to Ganonoque Cadillac in Ontario, treating the customer right!

 

[ryelou]

How did you go about dialing back the tune? It was suggested by Terry to change the fuel bias to 20 across the board, which I think dials or back as you get to the top end? I tried it and it did seem to shift better without any issues. Power wasn’t noticeably down, either. This weekend I’ll try to get some dragy times with map 0, map 1 and map 1 with fuel bias changes. I just need to find a place I can do some 1/4 mile runs.

 

[Andrew1127]

Follow Terry's instruction. The only time you'll have shifting issues I find is in the lower gears and WOT, whether from a slow roll (still in lower gears) or a dig. I did use fuel bias to tune it down along with lower targets (map6). Fuel bias has much more of an effect than the target from what I've found, i.e depending on the fuel bias setting you can push target higher and it doesn't have much effect, I think the fuel bias setting is how much the jb4 allows the MAF readings to fool the ecu.

I can't run fuel bias at 20, as it makes my car overboost and misfire during shifts in the lower gears, I normally get a misfire in the 18.5+ psi range. So after mad trial and error, I've set my settings to allow for 17-18 psi during the overboost during lower gear shifts, if I did a 4th gear pull it would be more like high 16 at tip in and moving down to 15 psi up to 5500rpm, and quickly down to 12-13 psi toward 6kish. Kind of the reason I decided to get plugs done, since I'm not pushing as much boost overall as I'm trying to compensate for the overboost (can't target boost only in the problematic gears). The dyno chart and logs on the jb4 website show 17-18psi all the way to 5kish then tapering down to redline.
Stock car pushes 14.5-15.5psi at tip in, and down to 12 by 5k, and 9-10.5 at 6kish to give you an idea what the jb4 is doing compared to stock.

Are you looking at your logs? Maybe do some research and get a little bit of a understanding of what your seeing if your unfamiliar. Your car might be able to handle more boost then mine before misfiring but only way to know is if you post up your log or look at it. Especially since we all have different climates/cars/fuel etc, what works for you might not work for me and vice versa. If your not getting misfires when launching then all is good, but if you are then shoot terry a log and see what he asks you what to do to your settings (which is probably apart of his RnD, only so much he can do with a short time borrowing someone's car)

Again only time you should be getting the misfire (if your situation is like mine) is right after/during the shift in lower gears, usually 2nd-3rd is the biggest spike but the odd time I've gotten in on 3-4 or 1-2 but it's pretty rare. If you would like to avoid all the TC alarms if you hear it starting to misfire- let off, it'll only give you the misfire/flashing CEL rather than light your dash up with alarms, if you do it early enough it won't even set a CEL. Where I have the car set I haven't gotten a misfire for a couple weeks, and thats with some digs with other cars, and WOT from slow rolls. I tried to test out a bunch of scenarios when I was adjusting my map6 to give me problem free driving so I never had to worry when I choose to get on the throttle.

Shoot me a log, I'm curious what they look like also!

 

[ryelou]

I’ve only had that one time of bad misfires that prevented it from revving further or shifting. I have been sending logs to Terry and his suggestion was the fuel bias to 20. I only had a short trip with it to go pick my kids up after school but it seemed better than what it was before, and what it was before wasn’t problematic. I have been logging my runs but they’re a mess to look at. I’ve only had two from a dead stop. The others were a mix of 5mph rolls to catch 1st and work my way up and I had a couple starting in 3rd too. I know what I’m looking at from a universal data perspective, but I don’t know the ins and outs of the JB4 and things like fuel bias that adjusts what the MAF sees, so that’s what I have to look up when it’s suggested (which I did earlier).

PM me your email address or phone number. I can send the graphs or log files.

 

[BrisketEnds]

How's everyones JB4's doing? interested in getting one.

 

[Andrew1127]

I enjoy mine, do your research on jb4's. Be prepared to get plugs, and look into it. It's still in beta phase, CELs are still I thing, mainly blowout/misfire (though currently I haven't gotten one since I got it dialed in). I'm getting my new plugs in next week, then I'll be able to really take advantage of the jb4. It's pretty detuned due to blowout, which comes with the territory, unlucky for us our cars are a PITA for plug install.

I'd recommend anyone to get it as long as they are prepared for the things that go with it. Terry has been pretty responsive to things that are brought up to him. Remote start issues were resolved with the newer units (though I only got to test during the tail end of winter), and the power in my opinion is way more consistent.

I just picked up my ps4s' today, will be getting them installed tomorrow. Won't be doing any draggy runs until I get them broken in. Chances are they'll be broken in after I get my plugs done sooo draggy runs to come when I get the car dialed in again!

 

[ryelou]

Andrew and I have talked a lot about ours. My experience has been similar, but maybe a little better since he helped sort out a lot of the early issues. I've never experienced any remote starting issues and I've had some cold Michigan days. And through the input of Andrew, myself and others, the tune the JB4 ships with is different than what it started at for him and I, which should help any of the misfires. I, too, am at a point now where I have it set at something 100% reliable and I don't have to worry about misfires or anything. It drives like stock with more power.

Andrew's point about detuning and leaving some on the table is correct, but it's a matter of perspective. With any car and any type of aftermarket upgrades you're going to get some cars you can push a little further than others. Andrew may be 5hp ahead of me, and someone else may be 5hp ahead of him, but we're all ~50hp over stock

 

[Andrew1127]

Didn't think I'd giver a draggy run, but in the name of curiosity had to get it done. Had to adjust my settings down a tad, for whatever reason I did get a misfire/blowout for the first time in a 1-2 months.

Draggy attached, slightly lowered jb4 power to avoid blowout. Best out of 2 runs 12.68 @ 108.09. Best I've done on the stock wheels + winters was 12.79/12.80 @ 106-107(depending on the run) on my previous settings that were a bit higher. Weight difference approx 7-8lbs per wheel+tire, and obviously on ps4s' and not winters. It was pretty cool this morning, drove my son to school plus a little drive to warm the tires up a bit. Currently weather network saying 3C and -3 with windchill, I know when the tires are cold I get a bunch of wheel hop but none on these runs, not ideal temps, but I'm headed 7hrs away tonight to go fish some salmon down in Niagara, and Monday I'm getting plugs put in.

Everything I find on the interwebs says the car is 4.9 to 60mph and 13.3 to the 1/4. Jb4(lower settings), panel filters, and aftermarket 19s.

I'll post up another draggy hopefully next week if the plugs go well and get the car dialed in with higher settings.

 

[ryelou]

I think that's awesome. And even for dialed down settings, that's over .6 seconds off a factory 1/4 mile time. Nice work!

 

[BrisketEnds]

Impressive numbers, even on the lower end of the JB4. Have you thought about adding meth injection? I'm sure your IAT temps are pretty nice right now in that 3C range lol

I've been looking around the internet for more information about these cars and Andrew seems to be the only public one. I appreciate the information you have shared so far man. Keep it up and good luck. Hope to see some nice numbers after that plug swap.

Just wondering, what plugs and gap are you going with?

 

[Andrew1127]

Thanks! Yeah wasnt info out there when. I was interested, that's why I post. OEM Acdelco plugs .022-.023

 

[Andrew1127]

Some misinformation from the shop's source. Plugs hopefully in Friday next week. Will keep updates posted.

 

[Andrew1127]

Well gapped down to .022, and it didn't fix the misfire issue. I'm guessing where I had the car was basically the limit to what the car will do with the current jb4

 

[Andrew1127]

Got out testing last night to adjust settings, and test to make sure I had settings for daily driving. Was able to eek a bit more out without misfires, but still having misfires if set too high. 4th gear pull looks much more similar to the dyno log posted by terry, and no misfires with launches and a good bit of aggressive daily driving. Was able to keep beside a recently dyno'd(a few weeks ago) 375whp manual FBO Golf R from a roll(only reason was auto paddle shifting vs his manual) but dusted him on a launch (launch control ftw).

Didn't do a draggy run, but plan on doing one in the near future, it's also quite a bit warmer so we will see what the car can do with these settings.

I'll be looking to do some E20 testing (mixed with 94) to see if it's worth while but last time it didn't have too much of an effect as I think the 94 was sufficient enough for the ecu to not pull timing.

 

[Junbug23]

Got out testing last night to adjust settings, and test to make sure I had settings for daily driving. Was able to eek a bit more out without misfires, but still having misfires if set too high. 4th gear pull looks much more similar to the dyno log posted by terry, and no misfires with launches and a good bit of aggressive daily driving. Was able to keep beside a recently dyno'd(a few weeks ago) 375whp manual FBO Golf R from a roll(only reason was auto paddle shifting vs his manual) but dusted him on a launch (launch control ftw).

Didn't do a draggy run, but plan on doing one in the near future, it's also quite a bit warmer so we will see what the car can do with these settings.

I'll be looking to do some E20 testing (mixed with 94) to see if it's worth while but last time it didn't have too much of an effect as I think the 94 was sufficient enough for the ecu to not pull timing.

Hey Andrew noticed it’s been about a month since you posted anything on the JB4
Anything new all the kinks worked out ?
Are tighter plugs necessary? About to pull the trigger but need to know what I’m getting myself into.
Thanks for all the feedback. Really appreciate it

 

[Andrew1127]

No changes from the last update really. OEM plugs gapped at .022 didn't fix change the misfiring if settings are too high (I wouldnt do plugs again - hindsight until the jb4 is able to command more from the car). Not sure what fuel you have access to, but I wouldn't run anything less than 93 octane.

I recently got an oil change and had the jb4 removed for service, and in my opinion if you can live with lower settings, and not getting all the available power from the jb4, along with it is still in beta, I'd get it again. It definitely adds performance, and is absolutely noticeable. Be aware you may pop a code. Unless you can wait for an undetermined time frame for trifecta / Tapout to pump something out (and are willing to flash your ecu) I'd get it.

I suggest for problem free from the get go, set fuel bias to 5 through all the rpm ranges and 0 at 6000rpm. Run 93+, I've never ran anything less than Canadian 94 in my car, but I've heard of issues with guys running 91(both on the Canadian side and American side 91), can't speak for everyone but my suggestion is to run higher octane fuel for the beta phase (as I haven't ran into these issues personally).

If you do want to play with ethanol, I find my car responds best at 15-20% e85, anything much more feels sluggish and is reflected by dragy times. I've never tried anything about e30 mix.

Lemme know if you have any other questions.

 

[Junbug23]

No changes from the last update really. OEM plugs gapped at .022 didn't fix change the misfiring if settings are too high (I wouldnt do plugs again - hindsight until the jb4 is able to command more from the car). Not sure what fuel you have access to, but I wouldn't run anything less than 93 octane.

I recently got an oil change and had the jb4 removed for service, and in my opinion if you can live with lower settings, and not getting all the available power from the jb4, along with it is still in beta, I'd get it again. It definitely adds performance, and is absolutely noticeable. Be aware you may pop a code. Unless you can wait for an undetermined time frame for trifecta / Tapout to pump something out (and are willing to flash your ecu) I'd get it.

I suggest for problem free from the get go, set fuel bias to 5 through all the rpm ranges and 0 at 6000rpm. Run 93+, I've never ran anything less than Canadian 94 in my car, but I've heard of issues with guys running 91(both on the Canadian side and American side 91), can't speak for everyone but my suggestion is to run higher octane fuel for the beta phase (as I haven't ran into these issues personally).

If you do want to play with ethanol, I find my car responds best at 15-20% e85, anything much more feels sluggish and is reflected by dragy times. I've never tried anything about e30 mix.

Lemme know if you have any other questions.

Really. Damn nothing less than 93 that’s a lil pricy out here in California haha

 

[Andrew1127]

Yeah, I'm only talking about a couple guys that encountered issues. Not sure how many people are out there and what they use. Is ethanol available for you? I think terry used during his dyno testing a E20 mix with 91 if you really want to go the jb4 route.