[F87source]

Originally Posted by cookiesowns

Thanks for the shout out!



Charlie, I wish I had the pleasure of seeing this thread and a chance to talk to you about your car to see how we can help you before the decision was made.

The points that you mentioned all sound strictly like a tuning issue and can be refined, may just take some time.

We've done quite a few M2's already on both XDI and Dorch pump running flex fuel with ECUTek and none has described the issues you mentioned. Granted our data set may be smaller than others, as only one of them being a DCT car ( rest 6MT ), I'm quite confident we can definitely sort you out on the tuning side.

I'd be more than happy to extend an offer of reviewing your logs, and seeing if we can get you to try out ECUTek to see if it resolves or improves your issues.



When you get into modifying the fuel system, or really any other component of such sensitive motors, you really need to dial in the tolerances on everything else, that's more than just fuel maps. Things like torque management, tip in control, HPFP/LPFP control so on so forth, nonetheless what's even more important is having *SOLID* data logging, meaning 15+ datapoint per second if not more, and logging custom ram addresses to get more visibility.

I won't get into the what's better or not debate here, but it's important to pick a tuner that really spends the time to understand the car, the driver, goals, and also the tuning platform and what's available to them.

Interesting, I will like to give you guys at Bend calibration an opportunity to tune my car when the time comes, just like tuning options I am more than open to try different tuners to see what they can do for me - I may favor a certain tuner/tuning platform but I am not hard stuck on one particular thing.


I see you offer tuning for MHD as well, I will likely stick with that first so I don't have to spend money on multiple tuning platforms for no reason.

This is another huge reason why I fricken hate OTS maps, because there is NO SUCH THING as one size fits all.

[PSG James]

Originally Posted by nothingman

It's an issue which began immediately after I had the PS2 and XDi HPFP installed. It usually occurs around 2,000-2,500 rpm in 6th or 7th gear between 60-80mph when driving the car normally down the road. Having DCT may make it more evident since I'm not manually shifting gears when I'm just cruising. When it happens, the car pulls a ton of timing for a split second.

My PS2 was installed by Frank at TTFS, who is also the exclusive distributor for the XDi HPHP and wrote the fuel maps. I had Frank check and replace the spring in the DV+, check the turbo installation for leaks, replace the plugs twice with both OEM Bosch and NGK 95706, tried different gaps, replaced the O2 sensor, tried both MHD and BM3, tried different tuners... nothing fixed it. That's why I went the path of this big turbo upgrade thinking replacing everything would fix it by process of elimination. Throwing good money after bad... a foolish mistake and never a good idea.

I uploaded a few of my datalogs taken in August but posted to Datazap on 11/20/2020 in case anyone would like to look through them:
https://datazap.me/u/nothingman/

I've talked to at least 10 other people with the same configuration with the same exact problem. Some of those people have the Dorch HPFP, so it's not strictly XDi. I haven't talked to anyone running Spool. This past weekend, I was messaging back and forth with boldy1, who is also having the same problem and we went back and forth with our findings. He even replaced his ignition coils. I was about to order a Precision Raceworks ignition kit to see if that resolved it, and then came across yet another person with the problem that had already tried that. That's when I decided to abandon the project.

The only people I know (count:2) who are running either a Pure Stage 2 turbo or Stage 3 Speedtech kit and aren't having the problem are using different HPFP solutions. One is using an S55 HPFP retrofit, the other port injection.

I've always wanted to own a blistering fast turbo charged car, but I think chose the wrong platform to pursue it with.

Hey, I came across your thread and find it very interesting.

I have a N55 M135i and had similar issue. My initial goal was to push over 500 HP with only pump gas (98) as I don't want port inject or meth injection kit because I daily drive my car, therefore I want it to be as convenient as possible, just fill gas and GAS!

I followed the "standard route", upgrade HPFP, turbo, intercooler, downpipes etc. But it never worked out. Eversince stage 2, I kept having misfire at around 4000 rpm due to fuel pressure drop. So upgraded to Dorch stage 1 HPFP, ran into the same problem, then people suggesting B58TU pump which they claim it could handle over 500 WHP, easy. Ok fine, bought it, retrofitted it to N55, hoping it would fix the fuel drop problem. But nope, it doesn't. it couldn't even handle 470 HP.

Fueling seems to be the biggest problem for N55s, but nobody really talks about it and many claiming big numbers on dyno (similar setup as mine), therefore, I seriously doubt those numbers.

So now, I am also retrofitting S55 pump on my M135i. There aren't many information about S55 pump retrofit on the forums, so my friend spent countless of hours finding solutions to make it work, activating the 2nd fuel pump, no "extra controller for the 2nd fuel pump or signal splitter or sorts and without any "hardware modification" on the S55 fuel pump.

Luckily, he was able to find solutions for all the problems we were facing, we are now in testing phase. Just test drove the car today, it drives like a charm. Pushing around 530 HP & 700 NM, no more fuel pressure drop (98 fuel). As soon as the car is completely finished, I will share datalogs and dynosheet if you are interested. Cheers.

James

[nothingman]

Originally Posted by PSG James

So now, I am also retrofitting S55 pump on my M135i. There aren't many information about S55 pump retrofit on the forums, so my friend spent countless of hours finding solutions to make it work, activating the 2nd fuel pump, no "extra controller for the 2nd fuel pump or signal splitter or sorts and without any "hardware modification" on the S55 fuel pump.

Luckily, he was able to find solutions for all the problems we were facing, we are now in testing phase. Just test drove the car today, it drives like a charm. Pushing around 530 HP & 700 NM, no more fuel pressure drop (98 fuel). As soon as the car is completely finished, I will share datalogs and dynosheet if you are interested. Cheers.

Nice! That's a solution that didn't occur to me at the time and in retrospect it seems pretty obvious. It's interesting that Frank (TTFS) had actually installed an S55 fuel rail with dual HPFP's on an N55 M2 several years ago around 2018, but it must not have occurred to him as a solution to this problem either.

Oh well, in the end I moved platforms and I'm happy where I am now so no complaints.

[PSG James]

Originally Posted by nothingman

Nice! That's a solution that didn't occur to me at the time and in retrospect it seems pretty obvious. It's interesting that Frank (TTFS) had actually installed an S55 fuel rail with dual HPFP's on an N55 M2 several years ago around 2018, but it must not have occurred to him as a solution to this problem either.

We also read about this M2 with TTFS S55 hpfp retrofit. But I can't find more info on that car. And software adjustment is not mentioned in their S55 dual hpfp package's description.

"dual fuel system setup consist of genuine oem M4 S55 fuel system that has been modified to work with the N55 engine"

So we believe it is done differently. But anyway.. as long as it works, then it works 😁

Just had mine dyno'd yesterday, we expected 530hp, but it was not. Here's the dyno sheet, 100% honest dyno result, no manipulation.

When I did the test drive, it was on the first "test file" - 493hp, but I seriously think it's pushing more than that. This is a 100-180 pull that I did -

However, it is not completely finished and is currently 514hp.

[nothingman]

Originally Posted by PSG James

We also read about this M2 with TTFS S55 hpfp retrofit. But I can't find more info on that car. And software adjustment is not mentioned in their S55 dual hpfp package's description.

"dual fuel system setup consist of genuine oem M4 S55 fuel system that has been modified to work with the N55 engine"

So we believe it is done differently. But anyway.. as long as it works, then it works 😁

The guy that owns that car is local to me and is actually a buddy of mine. Frank also did a car with the S55 pump in TX. Unfortunately, the local guy doesn't exactly how Frank programmed the fuel maps but I would imagine it probably involved taking the stock fuel maps from an S55 car and copying and adapting them to the N55.

Your progress looks really promising! Nice work!

[PSG James]

Originally Posted by nothingman

The guy that owns that car is local to me and is actually a buddy of mine. Frank also did a car with the S55 pump in TX. Unfortunately, the local guy doesn't exactly how Frank programmed the fuel maps but I would imagine it probably involved taking the stock fuel maps from an S55 car and copying and adapting them to the N55.

Your progress looks really promising! Nice work!

Thanks a lot.

To simply copying S55 fuel map onto N55 won't work. I can't reveal too much info as Gert spent literally weeks looking at electric diagrams, hardware comparisation, software difficulties.