[DaviTuned]

So, I have a completely stock 17" M240xi, and I am tuning it with a Pure 800 on e30, and I receive a fuel cut at 3000-3300 rpm when datalogging on BootMod3.

Here is a link to my datalog (Pure 800 + e30 custom map):

https://www.bootmod3.net/log?id=64d0...729ba022f27bde

I have been changing the fuel scalar and fuel correction table, but I am still running out of fuel.

Questions:
#1 Is it safe to push a Pure 800 on e30 targeting 24-26psi?
#2 Since HPFP is crashing should I continue to add fuel in increments until it stops crash?
#3 I tested the stage 2 e30 map, and car runs fine. So, I should I lower boost or continue to try to scale fuel scalar + fuel corrections?
#4 What are signs I should be aware of fuel system not able to keep up?

Always open to criticism/any suggestions of anything that looks wrong in data logs.

Thanks in advance!

[n55david]

Originally Posted by ijosuedavi

So, I have a completely stock 17" M240xi, and I am tuning it with a Pure 800 on e30, and I receive a fuel cut at 3000-3300 rpm when datalogging on BootMod3.

Here is a link to my datalog (Pure 800 + e30 custom map):

https://www.bootmod3.net/log?id=64d0...729ba022f27bde

I have been changing the fuel scalar and fuel correction table, but I am still running out of fuel.

Questions:
#1 Is it safe to push a Pure 800 on e30 targeting 24-26psi?
#2 Since HPFP is crashing should I continue to add fuel in increments until it stops crash?
#3 I tested the stage 2 e30 map, and car runs fine. So, I should I lower boost or continue to try to scale fuel scalar + fuel corrections?
#4 What are signs I should be aware of fuel system not able to keep up?

Always open to criticism/any suggestions of anything that looks wrong in data logs.

Thanks in advance!

You need to do a wot log from about 2k up to at least 6500rpm in 3rd and if you can 4th as well with traction control completely OFF.. What you posted looks like an idle log with random throttle blips.

The main question is.. what HPFP are you running?

[DaviTuned]

Originally Posted by n55david

You need to do a wot log from about 2k up to at least 6500rpm in 3rd and if you can 4th as well with traction control completely OFF.. What you posted looks like an idle log with random throttle blips.

The main question is.. what HPFP are you running?

I am using stock HPFP, and I did three WOT pulls inside the log. It is just fuel and boost cut immediately. If you look at the boost peaks those are my pulls.

[Oem.plus]

Originally Posted by ijosuedavi

I am using stock HPFP, and I did three WOT pulls inside the log. It is just fuel and boost cut immediately. If you look at the boost peaks those are my pulls.

Stock HPFP will not be able to support your current boost target. You're also over-boosting which is causing throttle closer.

I'd suggest bringing boost back down to 16psi and plan to get a TU Pump. Even then the TU pump would limit you to about 22psi on a e40 mixture.

[DaviTuned]

Originally Posted by Oem.plus

Stock HPFP will not be able to support your current boost target. You're also over-boosting which is causing throttle closer.

I'd suggest bringing boost back down to 16psi and plan to either get a TU Pump. Even then the TU pump would limit you to about 22psi on a e40 mixture.

Yeah, I ended up lowering boost to about 20 psi and adding some fuel, and I did notice I was overboosting, but no more closures.

Here is a new datalog:
https://www.bootmod3.net/log?id=64d1...90c62e93aa15ea

Tonight I will post a real WOT log.

My goal is to push this pure 800 to its max on e30 before I upgrade fuel pump, and then I will remap for new pump.

[n55david]

Originally Posted by ijosuedavi

I am using stock HPFP, and I did three WOT pulls inside the log. It is just fuel and boost cut immediately. If you look at the boost peaks those are my pulls.

You might be lucky to get 18psi on e30 with the stock hpfp.. MAYBE

Likely youll need to drop back down to 16 or 17psi.. You can try 18psi on e15-20.

[Oem.plus]

Originally Posted by ijosuedavi

Yeah, I ended up lowering boost to about 20 psi and adding some fuel, and I did notice I was overboosting, but no more closures.

Here is a new datalog:
https://www.bootmod3.net/log?id=64d1...90c62e93aa15ea

Tonight I will post a real WOT log.

My goal is to push this pure 800 to its max on e30 before I upgrade fuel pump, and then I will remap for new pump.

You're getting quite a substantial drop of Rail Pressure around 3400rpm. I believe you are reaching the limitations of the stock hpfp. One thing that may help is the rail pressure homogen table (KF_PRAIL_H).

Adjust the 140 load area after 3000rpm to 21 instead of 20. It's a multiplying factor for the hpfp to target a higher rail pressure. I use this method to catch the dip from the hpfp. Once rpms get high enough the rail pressure should smooth out.

[Trailbraker1098]

Spot on gents.


Stock pump gets whipped quickly when adding e to the mix. Stage 2 with e30, even at the 17-18 boost range on a stock turbo I was getting rail pressure drops. Not crash level, but enough the car was pulling timing. On every log, shortly after the pressure drop the timing would pull on a few cylinders. Switched to a TU pump and it’s been great up to 20lb range so far.

[Oem.plus]

Originally Posted by Trailbraker1098

Spot on gents.


Stock pump gets whipped quickly when adding e to the mix. Stage 2 with e30, even at the 17-18 boost range on a stock turbo I was getting rail pressure drops. Not crash level, but enough the car was pulling timing. On every log, shortly after the pressure drop the timing would pull on a few cylinders. Switched to a TU pump and it’s been great up to 20lb range so far.

TU Pump holds up to e40 really well. I was able to get 22psi on e40 targeting 12.6 afr, 14.5 degree of timing. Quite a night and day difference in performance. I was able to run quite a few OTS tuned B58s and came out ahead about 2 to 3 car lengths.

[JMcLellan]

Originally Posted by Trailbraker1098

Spot on gents.


Stock pump gets whipped quickly when adding e to the mix. Stage 2 with e30, even at the 17-18 boost range on a stock turbo I was getting rail pressure drops. Not crash level, but enough the car was pulling timing. On every log, shortly after the pressure drop the timing would pull on a few cylinders. Switched to a TU pump and it’s been great up to 20lb range so far.

When I had the stock fuel pump I was running into trims maxing out and rail pressure drops. This was running like an E15 blend, stage 2 with the stock turbo. I would be installing a stage 2 HPFP immediately if I had the pure 800 setup.

[DaviTuned]

Originally Posted by JMcLellan

When I had the stock fuel pump I was running into trims maxing out and rail pressure drops. This was running like an E15 blend, stage 2 with the stock turbo. I would be installing a stage 2 HPFP immediately if I had the pure 800 setup.

Yup, that is the next step in the process!