2020 C43 JB4
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Mercedes C43
2020 C43 JB4
I wanted to know if there are people who have a JB4 on a 2020 c43. If you guys have just that can you guys please send me some 0-60 tests just so I’m sure I’m getting around the right numbers.
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Getting the launch perfected makes the most difference on short 0-60mph times. If trying to evaluate tuning performance 1/4mile trap speed is a better measurement, or 60-130. 
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2020 C43
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2020 C43
Maybe your referring to the green fuel wire that is not necessary until blending? I guess you can say BCM isnt NECESSARY, but if you want the most power out of facelift models than inwpuld get it.im sure BMS will chime in on this.
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Mercedes C43
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20' C43 AMG
I was told the BCM is "optional" and really only intended if you plan on running higher boost targets i.e. ethanol blend etc by BMS. If I only intend to run pump gas and just the JB4 on a 2020 C43, can anyone tell me ball park numbers that we should be seeing?
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If you have a facelift car and you want to get the same level of gain as a PFL, you need the BCM. Due to changes in the WGDC, the car won't hold the boost that the JB4 is trying to dial in. That's regardless of meth or any other changes. If you have a 2019 or 2020, do yourself a favor and get the BCM so that you can hold boost levels that PFL cars do with the same mods.
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If your car is a 2019 or 2020, you can still run map 2 on 93+, but your gains won't be the same due to boost falling off. You'll have to also buy BMS's BCM so that you hold the boost levels that the JB4 is requesting.
Here's a summary of each map and the requirements for them.
JB4 Map Guide as of v6 firmware:
Map 0: Disables tuner
Map 1: Up to 4psi over stock peak, suitable for all 91 octane+ fuels
Map 2: Up to 5psi over stock peak, suggested for 93octane+
Map 3: Up to 5.5psi over stock peak, slightly more aggressive version of map2
Map 4: Up to 6psi over stock peak, suggested for E30+ or unleaded race gas mixtures
Map 5: Up to 7psi over stock peak, holding more boost to redline, suggested for E30+ or unleaded race gas mixtures
Map 6: User definable map, boost over stock entered on user adjustment page
Map 7: WMI (water/meth injection) progressive map for BMS FSB integration
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Last edited by Howyalivin; Aug 24, 2020 at 09:23 AM. Reason: clarifying something
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20' C43 AMG
Thanks for the clarification. I sure hope BMS is working on a remedy besides "spend more money and buy a BCM". If you own a Facelift model i.e. 2019+, you have to spend an EXTRA $200 to accomplish the same thing as Pre-facelift models.
That's extremely discouraging for us with newer models. Why should we have to spend extra money to accomplish the same thing as earlier models?
That's extremely discouraging for us with newer models. Why should we have to spend extra money to accomplish the same thing as earlier models?
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Acura TL-SH, among others
Thanks for the clarification. I sure hope BMS is working on a remedy besides "spend more money and buy a BCM". If you own a Facelift model i.e. 2019+, you have to spend an EXTRA $200 to accomplish the same thing as Pre-facelift models.
That's extremely discouraging for us with newer models. Why should we have to spend extra money to accomplish the same thing as earlier models?
That's extremely discouraging for us with newer models. Why should we have to spend extra money to accomplish the same thing as earlier models?
https://stratifiedauto.com/blog/what...-turbo-setups/
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No, you don't need DPs. If you aren't getting the performance you expect, meaning quarter miles that are between 6 tenths and 9 tenths quicker on map 2, you should reach out to BMS and start looking at your logs. If you have a Dragy, run a few pulls in map 0, then a few on map 2, and check the difference in times. For comparison, at decent altitudes and temps, a stock pre-facelift C43 should be able to run 12.8 to 13.0 in the quarter. On map 2, they've been able to get to 11.9 on the fastest ones, to about 12.2 on the low end. The facelift cars are as much as 2 tenths faster stock, but they don't get the same uplift from ECU side mods, because they are already running slightly higher boost.
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C43 AMG
that is a great read. I have heard FL has a bigger turbo than the PFL, so do we have more efficiency top end compared to the PFL then? Or at what whp do we need to change the turbo for more top end power? I personally like power all the way to the top instead of the OEM style of strong down low and falls on its face past 4k rpm..
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2019 C43 Coupe (W205)
If you have a facelift car and you want to get the same level of gain as a PFL, you need the BCM. Due to changes in the WGDC, the car won't hold the boost that the JB4 is trying to dial in. That's regardless of meth or any other changes. If you have a 2019 or 2020, do yourself a favor and get the BCM so that you can hold boost levels that PFL cars do with the same mods.
I am admittedly not anything close to very knowledgeable and just basing all this on what I have been told by others.
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that is a great read. I have heard FL has a bigger turbo than the PFL, so do we have more efficiency top end compared to the PFL then? Or at what whp do we need to change the turbo for more top end power? I personally like power all the way to the top instead of the OEM style of strong down low and falls on its face past 4k rpm..
If you plan to run aftermarket turbos, there are a lot of other things that need to change, so cost quickly becomes an issue. The simplest is fueling. The stock fuel pump isn't going to work with an aftermarket turbo setup. You should also change the intercooler. There's been plenty of talk that the stock rods aren't strong enough for an aftermarket turbo build either, so you would have to have custom ones made. There's an older thread where a person has all the specs for his listed. If you search you should be able to find it, but there were a sizeable number of changes that had to be made to accommodate the new turbos.
The fastest I have heard of a stock turbo setup running is 11.1's, without DP I believe. Not sure if the person had meth, but definitely used race gas, a JB4, and ported stock turbos. They also had one of the fastest cars on this site before doing that. I can't say the person themselves came on to talk about it. We heard about it from someone else that was at the track when it happened. I can't recall if the timeslip was posted.
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I have been told that the 2019s have been limited by many of the ECU settings now also being controlled by the CPC (Central Powertrain Control). I have already have EC V4 + DPs + E30 tune and had a new (customized) CPC/TCU upgrade done and certainly feels more responsive. I do not know if I can hold more boost yet or not until I do some logs and have a more agressive tune done that would give me more boost. I currently do not feel an awesome improvement yet. Based on this no matter what I do I will not see improvement. Is this correct and what does the BCM do that cannot be done through a tune?
I am admittedly not anything close to very knowledgeable and just basing all this on what I have been told by others.
I am admittedly not anything close to very knowledgeable and just basing all this on what I have been told by others.
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C43
I was talking about for JB4 cars. If you start tuning the ECU, you have control over a lot more features than a piggyback can access. The piggyback is essentially just lying to the stock ECU about what the sensor inputs are so that it makes the changes, according to its stock tables. It's why, once you remove a JB4, there isn't evidence of out of range values that can be recorded and accessed by the dealer. I'm not going to talk about ways that a manufacturer could identify that a piggyback had been on a car, let them think up their own methods.
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2017c43
If your car was made before 2019, all that you need is 93+ octane to run Map 2. Nothing else.
If your car is a 2019 or 2020, you can still run map 2 on 93+, but your gains won't be the same due to boost falling off. You'll have to also buy BMS's BCM so that you hold the boost levels that the JB4 is requesting.
Here's a summary of each map and the requirements for them.
JB4 Map Guide as of v6 firmware:
Map 0: Disables tuner
Map 1: Up to 4psi over stock peak, suitable for all 91 octane+ fuels
Map 2: Up to 5psi over stock peak, suggested for 93octane+
Map 3: Up to 5.5psi over stock peak, slightly more aggressive version of map2
Map 4: Up to 6psi over stock peak, suggested for E30+ or unleaded race gas mixtures
Map 5: Up to 7psi over stock peak, holding more boost to redline, suggested for E30+ or unleaded race gas mixtures
Map 6: User definable map, boost over stock entered on user adjustment page
Map 7: WMI (water/meth injection) progressive map for BMS FSB integration
If your car is a 2019 or 2020, you can still run map 2 on 93+, but your gains won't be the same due to boost falling off. You'll have to also buy BMS's BCM so that you hold the boost levels that the JB4 is requesting.
Here's a summary of each map and the requirements for them.
JB4 Map Guide as of v6 firmware:
Map 0: Disables tuner
Map 1: Up to 4psi over stock peak, suitable for all 91 octane+ fuels
Map 2: Up to 5psi over stock peak, suggested for 93octane+
Map 3: Up to 5.5psi over stock peak, slightly more aggressive version of map2
Map 4: Up to 6psi over stock peak, suggested for E30+ or unleaded race gas mixtures
Map 5: Up to 7psi over stock peak, holding more boost to redline, suggested for E30+ or unleaded race gas mixtures
Map 6: User definable map, boost over stock entered on user adjustment page
Map 7: WMI (water/meth injection) progressive map for BMS FSB integration
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https://www.morepowertuning.com/emix
