[x77md]

Hi all,

Was wondering if there’s any real difference in effectiveness or safety by going down the MHD tuning route compared to JB4 with a backend flash. Like the idea of being able to manage everything off the app with MHD and buying the maps etc but are there any drawbacks to MHD? Any reasons why I should consider JB4 over MHD other than it being around and more established?

Cheers

[coleybmw335]

Hi,

I was in the same boat, I ended up going with MHD with help from a member on this forum to decide, Like you said, MHD is easy for switching maps plus it is cheaper.

From what I read JB4 gives the false parameters, Even tho it has safety features.


I'm glad I chosen MHD

[x77md]

Originally Posted by coleybmw335

Hi,

I was in the same boat, I ended up going with MHD with help from a member on this forum to decide, Like you said, MHD is easy for switching maps plus it is cheaper.

From what I read JB4 gives the false parameters, Even tho it has safety features.


I'm glad I chosen MHD

Thanks! I’m more leaning towards the MHD just because it seems a hell of a lot more easier... could you recommend a battery charger to use when backing up the ecu and flashing?

[Mayorie]

Originally Posted by coleybmw335

Hi,

I was in the same boat, I ended up going with MHD with help from a member on this forum to decide, Like you said, MHD is easy for switching maps plus it is cheaper.

From what I read JB4 gives the false parameters, Even tho it has safety features.


I'm glad I chosen MHD

[coleybmw335]

I just brought a 8 Amp charger from Argos around £25 when I did mine

[Smokey33]

You will only need a trickle charger the first time you flash at most, even then it can be a few mins, I think it depends on your DME.

My custom map was lost when I had the software updated at BMW and when I flashed the map back on it only took 2 mins.

Im always for MHD. Its a proper tune. JB4 is no better than a tuning box its tricking the ECU.

[snedanator]

MHD all the way. And the CTek mxs 5.0 chargers are brill 👌 Always remember and get a recommended obd cable as some cheap amazon and fleabay ones will not work or will stop half way. Cableshack ones are fine...had mine 2 years now.

[leons335]

Originally Posted by Smokey33

You will only need a trickle charger the first time you flash at most, even then it can be a few mins, I think it depends on your DME.

I mistakenly left my charger on trickle charge when I hooked it up to flash my 57 reg 335 using MHD. Cue lots of dinging battery low warnings and increased discharge warnings. I had also flashed XHP shortly before so it may have been the impact of both flashes. I'd certainly recommend putting a charger on proper charge for a full flash though. Otherwise no issues and even only running Stage 1 the car feels much more alive compared to stock.

Pretty sure you could check battery voltage on the MHD read codes so worth a check before you start a flash.

[x77md]

Originally Posted by leons335

I mistakenly left my charger on trickle charge when I hooked it up to flash my 57 reg 335 using MHD. Cue lots of dinging battery low warnings and increased discharge warnings. I had also flashed XHP shortly before so it may have been the impact of both flashes. I'd certainly recommend putting a charger on proper charge for a full flash though. Otherwise no issues and even only running Stage 1 the car feels much more alive compared to stock.

Pretty sure you could check battery voltage on the MHD read codes so worth a check before you start a flash.

I've now recurved my OTG cable & Dcan from cable shack and looking to use this streetwize 8-12amp heavy duty battery charger I've picked up from Argos...

My current voltage for my battery is around 12.6-13V at ignition and 14.3+V with the engine running. For the initial write should I stick to the 8amp charge or 12amps? Or does it really not matter?

[KClemente]

Originally Posted by x77md

I've now recurved my OTG cable & Dcan from cable shack and looking to use this streetwize 8-12amp heavy duty battery charger I've picked up from Argos...

My current voltage for my battery is around 12.6-13V at ignition and 14.3+V with the engine running. For the initial write should I stick to the 8amp charge or 12amps? Or does it really not matter?

For a car with a good battery, as long as your voltage doesn't drop below 11.8 you're fine. I've flashed multiple cars without any sort of charger connected and they've all been fine.

I did flash one car with a bad battery, and I just jumped it onto another car and that worked aswell.

My opinion on the jb4 vs mhd is that it's BEST to pair them up together. You get the safety functionality of the jb4 and the proper tune at the same time. Stacked together, the jb4 does more than just show you gauges.

I wouldn't run my car with a high strung custom tune without my jb4 looking out for my motor

[x77md]

Originally Posted by KClemente

For a car with a good battery, as long as your voltage doesn't drop below 11.8 you're fine. I've flashed multiple cars without any sort of charger connected and they've all been fine.

I did flash one car with a bad battery, and I just jumped it onto another car and that worked aswell.

My opinion on the jb4 vs mhd is that it's BEST to pair them up together. You get the safety functionality of the jb4 and the proper tune at the same time. Stacked together, the jb4 does more than just show you gauges.

I wouldn't run my car with a high strung custom tune without my jb4 looking out for my motor

For now I'm going to try MHD alone, see how it goes... I'm planning on getting a custom tune later once I'm FBO as it's probably the best way to get the most power...

Attempted first flash today but got an error 'unable to erase memory' followed by windscreen wipers switching on. Read up online that it's possibly due to a dodgy otg cable. Bought another one today but as it's raining I'm gonna postpone the flash to tomorrow or Tuesday. Let's hope the car doesn't implode on the second try

Edit: weather cleared up and I flashed stage 1.... wow the power difference is phenomenal

[Juz5i]

Originally Posted by x77md

For now I'm going to try MHD alone, see how it goes... I'm planning on getting a custom tune later once I'm FBO as it's probably the best way to get the most power...

Attempted first flash today but got an error 'unable to erase memory' followed by windscreen wipers switching on. Read up online that it's possibly due to a dodgy otg cable. Bought another one today but as it's raining I'm gonna postpone the flash to tomorrow or Tuesday. Let's hope the car doesn't implode on the second try

Edit: weather cleared up and I flashed stage 1.... wow the power difference is phenomenal

Ooooh your tempting me now!!

[x77md]

My advice is go for it! I'm wondering why I didn't tune any earlier