BM3 plus JB4-thoughts?

[VETTEPRO]

I'm running BM3 Stage 2 with downpipes, intake etc. and I'm a little underwhelmed.
Who has done this and then added JB4 and what were your impressions? I'm OK with fabbing up larger intercoolers or adding Methanol injection, if needed.
Thanks

[BadCompany]

It seems like you should just do a custom tune with the bm3. Obviously, an OTS map isn't going to be perfect. I'm not sure what adding a jb4 is really going to do for unless you want to run it as a meth controller. What would be the purpose for the jb4? Again, probably just want a custom tune (and maybe meth). Or do multiple maps for e30, race, 93, etc. The S63tu is known for destroying rods though... I guess the ultimate question is what are you looking to get out of the jb4 that bm3 can't already do?

[GGreek5]

Originally Posted by VETTEPRO

I'm running BM3 Stage 2 with downpipes, intake etc. and I'm a little underwhelmed.
Who has done this and then added JB4 and what were your impressions? I'm OK with fabbing up larger intercoolers or adding Methanol injection, if needed.
Thanks

Jb4 by itself will give you what you're looking for.

[BadCompany]

Originally Posted by GGreek5

Jb4 by itself will give you what you're looking for.

What makes you say that? I'm curious why you think a piggyback is going to perform better than a custom tune. I think I read you were going to swap between the two and report your 1/4 mile times, but I'm not sure I ever saw the jb4 results vs BM3's Stage 1 OTS (whichever revision that was).

[tmaners]

I have a full bolt on F10 M5 (turbos, intercoolers, intakes, dps,
exhaust meth, tune, etc) making 757rwhp and almost 800tq. It's capable of making a lot more power, but it's proven once you surpass the 800hp and 800 tq mark, thats when these motors really start bending rods or spinning bearings. Yes it has happened to cars with less power, but as a whole this is the threshold I would be mindful of with your build. If you don't want to go with aftermarket turbos, I'd agree with the above comment and get to a dyno so that you can optimize the BM3 tune you're running and add meth. Use the JB4 as a meth control until only as it's tuning capability compared to the BM3 is is significantly less. If you want more speed then I'd advise that you consider an intake (RK Autowerks). They don't add a ton of power on these motors, but significantly increase its ability to breath up top in the rpm range thus substantially reducing 60-130 times (I have vbox and dragy confirmed 1 full second reduction from an intake on the F85 X5M's. Hit me up if you have questions on any of the above.

[BadCompany]

Excellent post. Thanks.

[GGreek5]

Originally Posted by BadCompany

What makes you say that? I'm curious why you think a piggyback is going to perform better than a custom tune. I think I read you were going to swap between the two and report your 1/4 mile times, but I'm not sure I ever saw the jb4 results vs BM3's Stage 1 OTS (whichever revision that was).

I haven't gotten a chance to get to the track since I've installed the jb4. It closed in October and doesn't re open until April. But map 2 is a whole hell of alot more power than the ots map on the bootmod.
I'm finally into the 3's on the draggy 0-60 runs, and the power just hits instantly on the jb4 as opposed to the bootmod which I only really felt the power in the high rpm range. Lack of a race gas map on the bootmod had me pretty bummed out also. In the nicer weather I usually run ms109 regularly. Custom tune is another story entirely. There are custom tuned X5m's trapping above 120s. I guess it's all relative to what someone is looking for in terms of power. Not knocking the bootmod. It's amazing, but for me not wanting a custom tune yet, Jb4 has the power the way I like it.

[BadCompany]

Originally Posted by GGreek5

I haven't gotten a chance to get to the track since I've installed the jb4. It closed in October and doesn't re open until April. But map 2 is a whole hell of alot more power than the ots map on the bootmod.
I'm finally into the 3's on the draggy 0-60 runs, and the power just hits instantly on the jb4 as opposed to the bootmod which I only really felt the power in the high rpm range. Lack of a race gas map on the bootmod had me pretty bummed out also. In the nicer weather I usually run ms109 regularly. Custom tune is another story entirely. There are custom tuned X5m's trapping above 120s. I guess it's all relative to what someone is looking for in terms of power. Not knocking the bootmod. It's amazing, but for me not wanting a custom tune yet, Jb4 has the power the way I like it.

I was approaching it from the "if you already have bootmod3, why spend the money for a jb4 when you can use that money for a custom tune?" Please do update that thread when the track opens again. I'm interested to see what you get.

[VETTEPRO]

I am a tuner and own my own dyno. I do not tune BMWs and don't want to learn how. My dyno is only 2 wheel drive as well, so I can't actually use it.
I only mention this so you'll understand that I know more than most about how a tune effects the vehicle. I write a lot of base tunes to send to my dealers and retail customers who purchase my supercharger systems. I know these tunes are deliberately soft for safety. I'm sure the BM3 tune is as well.
I just don't like the idea of paying someone $900 to slightly tweak a tune that has already been written. I wouldn't know who to trust and am not sure that I'm getting any sort of value. I can't sell it if I decide it's not worth it either.
If I go with the JB4, I can play with it and take it off if I'm not impressed with what it can do.
I was just looking for impressions from guys who have actually done it. I'm a zero to 60 or 80 type of driver. I like that hard hit in the lower gears. I will never (or hardly ever) do 60 to 130 runs. Runs in the lower gears is also a lot easier on the motor as the load is considerably lower.
I'm going to put it up on the rack today and see if I have room to weld up a custom methanol reservoir under the hood or in the fender somewhere.
I don't like the idea of a rear mounted tank. I like a front mounted tank with the pump being gravity fed close to it.
I plan on getting a newer one in a few months and I want things I can take off and transfer to the new one. I may seem crazy but I tend to keep modding my cars until the day I sell them.

[tmaners]

Yeah, I'm aware of who you are based on my Z06 days. I've been on the S63tu game a while with my M5 and agree on tuning being over priced, but I'll also vouch for a custom tunes ability to extract a lot more power from these cars. If you're looking for a good place, I'd highly recommend DME tuning as they are super familiar with our cars and Mo (owner) is very conscientious about setting them up in a safe manner. He's done mine and many others out there all with great results. I will however depart with your notion that dig racing in these cars is easier on components. These twin turbos are small and because they spool so fast create virtually peak tq around 2500 rpm. This is fine for stock but once you start modding these motors pick up a ton of tq and that's where most of the damage I've seen (bent rods, broken axles, sheered diff mounts) occurs.

To answer your specific question, I've seen comparison (ie real world race) between JB4 equipped cars and back end flash tunes and the JB4 just can't compete. Again, this is only my first hand knowledge of seeing these cars actually run on the street...

[F3085258]

You could get the xdelete app and turn off AWD and run your X5M in RWD to put on your dyno. https://www.xdelete.app/

[HydroStream6]

I have a 50i with exactly what you're asking. I have Bootmod3 Stage 1 (18lbs) stacked with a JB4. This combination is perfect for my needs. The 50i runs high 11s with just the BM3 Stage 1 flash and no other mods on 93 octane. When I want to push it a bit harder, I unplug the MAFs, add a few gallons of E85, and run the JB4 in map 1. This gives me ~21.5lbs and runs 11.7 consistently. The JB4 offers the flexibility that the flash doesn't, at least not nearly as quickly as the JB4. And the flash offers the added benefit of beefed up DME fueling, etc.

In all, the vehicle does hit loads harder with the JB4. I too find the BM3 flash a little soft. I also have 3.5bar map sensors to throw in one of these days if I ever want to go higher. I do get nervous about the rods in these motors though haha.

Hope this helps. Also, JB4s can be found used for CHEAP sometimes. I paid $150 for mine if I recall with the BT module. It was off an S63TU. I just had to flash the N63TU firmware to it. Hardware is the same.

Good luck!
Adam

[tmaners]

Good real world info. I completely agree that the JB4 gives the user an extremely fast way to alter maps, but to your point does so in a very limited fashion (ie...boost increase only vs a back end flash that provides adjustment to more parameters which usually equates to greater safety and reliability). I'll also attest to the fact that throwing in a little E85 helps drop those e.t's a good bit. I know when I run it (usually a E30 blend) it hits and pulls substantially harder.

Question...does anyone with BM3 know how many lbs boost the stage 2 map (cars with dps, etc) makes on the F85s? Thx

[VETTEPRO]

Originally Posted by tmaners

Good real world info. I completely agree that the JB4 gives the user an extremely fast way to alter maps, but to your point does so in a very limited fashion (ie...boost increase only vs a back end flash that provides adjustment to more parameters which usually equates to greater safety and reliability). I'll also attest to the fact that throwing in a little E85 helps drop those e.t's a good bit. I know when I run it (usually a E30 blend) it hits and pulls substantially harder.

Question...does anyone with BM3 know how many lbs boost the stage 2 map (cars with dps, etc) makes on the F85s? Thx

I saw 23# peak with their data logging. Is it accurate? I don't know.
I have a question about your previous post.
Were you comparing a standalone JB4 car against one with JB4 and a back end flash, or against one with a flash only?
Also, I'm not talking about dig racing at all. I'm talking about normal spirited street driving. I never actually nail it from a stop. I outgrew that years ago. The point I was trying to make was that there is less load on the engine itself in the lower gears as opposed to trying to pull in 6th gear or so. I see it on my dyno all the time. I'm much more likely to see detonation trying to run a supercharged car in 6th gear rather than 4th, as an example. It's even more evident on the road when trying to push a brick through the air at 140MPH. I see more guys breaking engines at top speed events than 1/8 mile drag racing. Driveline parts are another story entirely.

[tmaners]

Oh ok, thought you were talking from a dig. Yes of course the drivetrain takes a major beating from a dig, but I was saying I've seen plenty of these motors (FBO) get damaged from a dig due to the massive torque they make at low rpms. If you're just doing lower speed roll ons then yes, I agree definitely much safer/easier on both drivetrain and engine components.

My observations were stand alone jb4 vs backend flashes. I thought you were talking about running a jb4 instead of your BM3. Can you stack a jb4 on a backend flash...absolutely but guys in my circle report issues (stumbling, hesitations, etc) and by the time you buy a jb4 and blue tooth model you would of spend roughly the same amount as a revised flash so, imo I'd just rather go that route, but to each their own.

[KCTiger]

How much for a custom BM3 flash these days? Stage 1. I didn't think I would pursue this but tmaners makes it sound less expensive than I thought.

[tmaners]

I don't run BM3 (I have a a custom tune from DME which was $2600), but others with BM3 tell me they are roughly $900/$1Kish depending on who is doing the tune.