[GG87M2]

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Thoughts? Would you recommend/do it again?

Im itching for some lower rpm power. No others performance mods.

Does it work well with the manual and any concerns with clutch slip just using 93 octane?

Installation tricky? I have done it on an Alfa Romeo Quadrifoglio I had but I read one of the S58 sensors is a PITA. Anything with fuel connections - there was early mention of a fuel sensor connection I saw somewhere.
'TIA

[BroDoze]

To make a real difference on the low-end, I think you'll need to add some catless downpipes, along with the JB4. Get those turbos spinning sooner.

[mike@x-ph.com]

The jb4 will add power across the entire RPM range, but you can set it to only add power on low RPM

[BroDoze]

Originally Posted by mike@x-ph.com

The jb4 will add power across the entire RPM range, but you can set it to only add power on low RPM

Wait, so you're talking about reshaping the torque curve on an S58 - can a piggyback really do that?

My experience (limited to a catless 135i) was it more just took the stock curve and smoothed it out and majorly boosted the whole "torque floor" across the entire usable range. How soon the torque hit, never really changed, it was just a whole bunch more of it, when it did hit. Or my memory's failing. That was like 10 years ago, lol.

[mike@x-ph.com]

Originally Posted by BroDoze

Wait, so you're talking about reshaping the torque curve on an S58 - can a piggyback really do that?

My experience (limited to a catless 135i) was it more just took the stock curve and smoothed it out and majorly boosted the whole "torque floor" across the entire usable range. How soon the torque hit, never really changed, it was just a whole bunch more of it, when it did hit. Or my memory's failing. That was like 10 years ago, lol.

only the JB4 has a custom map which lets you select your boost by RPM and shape it the way you want.

[BroDoze]

Oh man. I may be going JB4 right away then.

How much tweaking and tuning do you think might be needed for a high-altitude, 91oct G87. Tons of logs back and forth with support? Or not a big deal? I'm not a tuner, lol.

[JMcLellan]

Originally Posted by BroDoze

Oh man. I may be going JB4 right away then.

How much tweaking and tuning do you think might be needed for a high-altitude, 91oct G87. Tons of logs back and forth with support? Or not a big deal? I'm not a tuner, lol.

I worked a lot with the JB4 technical folks a couple years back when I was getting into tuning my F series m240i. It's easy to run logs with the JB4 and they will review and provide feedback to help you get things dialed in. I'm debating on getting the jb4 or the racechip right now. I'm feeling lazy so leaning towards the racechip since it's more set it and forget it vs jb4 which you can get pretty deep into some tweaking. If you go with it add the Bluetooth connection kit to get the interface on your phone.

[Ginster6]

Originally Posted by GG87M2

Installation tricky? I have done it on an Alfa Romeo Quadrifoglio I had but I read one of the S58 sensors is a PITA. Anything with fuel connections - there was early mention of a fuel sensor connection I saw somewhere.
'TIA

yup. same thoughts. I had on my alfa GQV, and it was awesome... but the S58 is a turn off. so I have not install it. Still sitting in the box.

[mike@x-ph.com]

Originally Posted by BroDoze

Oh man. I may be going JB4 right away then.

lets do it

[GenXG87]

I've had it on my car since July last year. Mostly run map 2 on the street. No issues. I've never had any clutch issues with it. The IRL single mid pipe really woke it up with the JB4.

I ran an E30/40 mix for a couple tanks and played around with some custom settings and IAT spoofing. It was good but never really felt like it was WOW. Map 2 really was the sweet spot with no other mods. I never revisited after the mid pipe.

I'm moving to an ecu tune now since I do a lot of track days.

I never drag raced but did do a handful of dragy runs. Never had a clutch issue. I had an 11.78 @ 125 all stock with JB4 MAP2. Map1 was 11.88 @ 123. Not a great street with 2.0s 60ft.

[Xeon555]

I'm also thinking about doing a jb4 but worried about jerky power band or the throttle feeling like an on off switch

[mike@x-ph.com]

Originally Posted by Xeon555

I'm also thinking about doing a jb4 but worried about jerky power band or the throttle feeling like an on off switch

The Jb4 is not active under 3000 RPM and a certain throttle position, so driving is the same as stock under these conditions

[GenXG87]

Originally Posted by Xeon555

I'm also thinking about doing a jb4 but worried about jerky power band or the throttle feeling like an on off switch

On the street you won’t really notice that.

If you road race the car you may notice it coming on and off.

[Xeon555]

Originally Posted by GenXG87

On the street you won’t really notice that.

If you road race the car you may notice it coming on and off.

That would drive me nuts yes I do track the car here and there

[Xeon555]

Originally Posted by mike@x-ph.com

The Jb4 is not active under 3000 RPM and a certain throttle position, so driving is the same as stock under these conditions

I've just driven m cars with piggy backs and the power was very weird almost like the turbo was surging or the boost was fluctuating on wot

[mike@x-ph.com]

Originally Posted by Xeon555

I've just driven m cars with piggy backs and the power was very weird almost like the turbo was surging or the boost was fluctuating on wot

That should not be the case, if you have datalogs, i recommend sending them to BMS so they can take a look