[kern417]

Originally Posted by 540iSUP

So now that BM3 and MHD are coming out with Flex Fuel maps, would you suggest a Dorch Stage 2? I'm running stock turbo right now, but will upgrade to a hybrid sometime in the future. I plan on running some E-mix, but because its a Daily Driver/long distance Family car, I'm really looking into the Flex Fuel option. I don't race, its a 540i so its heavy, but I do have a heavy foot and like to go fast in the back roads.

So for running a Flex Fuel tune, what HPFP would you suggest. I was leaning towards Dorch Stage 2 so that I wouldn't have to worry about it at all, but if I can save some money and get away with a Stage 1 or even the TU pump, I would rather do that.

Flexfuel doesn't matter. Just like a turbo, the fuel pump limits how much power you can make. So pick whichever pump supports your peak hp goals.

500-600hp = TU/DS1
600hp+ = DS2

[540iSUP]

Originally Posted by kern417

Flexfuel doesn't matter. Just like a turbo, the fuel pump limits how much power you can make. So pick whichever pump supports your peak hp goals.

500-600hp = TU/DS1
600hp+ = DS2

Thanks Kern! Man, you've helped me learn so much about this platform through your posts and YouTube. I truly appreciate everything you're doing for the community.

[OzBMR]

For those who may have wondered "Could I run full E85 with MHD E40 Stage 2+ off the shelf map?", well I've been running straight E85 on this map for several months now, the logs look clean, the car runs smooth and the exhaust smell is more pleasant.

The Dorch Stage 2 HPFP holds target pressure perfectly.

I'm in a sub-tropical climate and it's coming into summer. The engine cranks a little more with cold starting than with an E40 mix, but nothing of concern. Once warm it starts the same as with straight 93. In a cold climate in winter cold starts would be more difficult.

Currently in Brisbane, Australia, E85 is AUD$1.74/litre and 93 (98RON) is currently $2.06/litre. Full E85 fuel consumption with city driving is around 12.5 litres per 100km (18.8 mpg) compared to E42 (50:50 93/E85) at around 9 litres per 100km (26 mpg) So it's less cost-effective than running the 50:50 mix of E42, but it's very convenient and it feels good to be using 80% plus renewables. I think highway driving with E85 may provide closer fuel efficiency to E42 but I'm yet to test this.

[kern417]

Sounds like a good way to max out trims and lean out at the worst moment.

[weehe126]

Originally Posted by kern417

Sounds like a good way to max out trims and lean out at the worst moment.

If he has the fuel pressure there shouldn't be any issues. Tuners normally go for leaner AFR when tuning for full E85. The fact that the tune is for E40 I would expect that to mean target AFR is a little richer, so would be safe. If trims are way off then possibly there would be an issue, but would need to see a log.

[OzBMR]

I didn't just jump from E40 to E85, it was a gradual progression with data logging and checking trims, fuel pressure and AFRs along the way. Trims, pressure and AFR are fine, thanks for your concern though Kern

[Glemm1970]

Originally Posted by OzBMR

I didn't just jump from E40 to E85, it was a gradual progression with data logging and checking trims, fuel pressure and AFRs along the way. Trims, pressure and AFR are fine, thanks for your concern though Kern

What is your boost and timing at full E85? Or are you using firmware for E40?

[OzBMR]

Originally Posted by Glemm1970

What is your boost and timing at full E85? Or are you using firmware for E40?

Standard MHD Stage 2+ HPFP E40 map, with Dorch Stage 2 HPFP and straight E85, stock turbo.

The weather here is currently quite warm, about 28 degrees C and IAT's around 45 degrees C

You can see in the log file a 4th gear pull, DSC off, there was quite a bit of wheel spin around 2800 - 3000 rpm. Fuel pressure and AFR's are as per the map targets, fuel trims are good.

Boost is 21 PSI from 3700 RPM to 6000 rpm, dropping a little to about 19 PSI by 6600 RPM.

https://datazap.me/u/ozbmr/mhd-stage...-28&zoom=17-57

[mike082802]

Originally Posted by OzBMR

Standard MHD Stage 2+ HPFP E40 map, with Dorch Stage 2 HPFP and straight E85, stock turbo.

The weather here is currently quite warm, about 28 degrees C and IAT's around 45 degrees C

You can see in the log file a 4th gear pull, DSC off, there was quite a bit of wheel spin around 2800 - 3000 rpm. Fuel pressure and AFR's are as per the map targets, fuel trims are good.

Boost is 21 PSI from 3700 RPM to 6000 rpm, dropping a little to about 19 PSI by 6600 RPM.

https://datazap.me/u/ozbmr/mhd-stage...#38;zoom=17-57

any dragy times? how's it feel?

[kern417]

Originally Posted by weehe126

If he has the fuel pressure there shouldn't be any issues. Tuners normally go for leaner AFR when tuning for full E85. The fact that the tune is for E40 I would expect that to mean target AFR is a little richer, so would be safe. If trims are way off then possibly there would be an issue, but would need to see a log.

It's an OTS map. It's not leaner than pump gas maps.

Having fuel pressure is good until you don't. There are other indicators that something is wrong, and even I myself have had some good pulls then one randomly backfires because of fuel pressure dips.

I've been following his progress in comments etc. I just don't agree with recommending it at all. 5% or so difference to clean up timing, sure. But you're asking for trouble running that long term. That's why his STFT goes up to 17%. That is not safe.

[Glemm1970]

Originally Posted by OzBMR

Standard MHD Stage 2+ HPFP E40 map, with Dorch Stage 2 HPFP and straight E85, stock turbo.

The weather here is currently quite warm, about 28 degrees C and IAT's around 45 degrees C

You can see in the log file a 4th gear pull, DSC off, there was quite a bit of wheel spin around 2800 - 3000 rpm. Fuel pressure and AFR's are as per the map targets, fuel trims are good.

Boost is 21 PSI from 3700 RPM to 6000 rpm, dropping a little to about 19 PSI by 6600 RPM.

https://datazap.me/u/ozbmr/mhd-stage...-28&zoom=17-57

There is no sense from the full E85 on this E40 firmware! You need 18 timing with a 21.5 boost from exactly 4500 to 6700 rpm. This is possible in custom firmware. But stok turbo this mode may not pull. Therefore, pour a maximum of E45 / 50. It makes no sense to load the pump.

[OzBMR]

Originally Posted by kern417

It's an OTS map. It's not leaner than pump gas maps.

Having fuel pressure is good until you don't. There are other indicators that something is wrong, and even I myself have had some good pulls then one randomly backfires because of fuel pressure dips.

I've been following his progress in comments etc. I just don't agree with recommending it at all. 5% or so difference to clean up timing, sure. But you're asking for trouble running that long term. That's why his STFT goes up to 17%. That is not safe.

Something must be wrong with your set up if you're randomly getting fuel pressure dips and backfires. I never get this. What are the other indicators that something is wrong?

STFT's up to 20% are fine, stop being dramatic. As long as the key logged values are OK I'm not worried. Running meth IMO is far riskier.

For comparison here's a log from July (cooler ambient temps) last year with the same map and E40 fuel mix. The STFT's are almost identical, as are all the other values, so I don't see what your concern is. https://datazap.me/u/ozbmr/ozbmr-mhd...24-25-26-27-28

Originally Posted by mike082802

any dragy times? how's it feel?

The car runs the same dragy and quarter mile times on E85 as it does on E40 as the map targets torque and fuel can't increase map torque values. Runs great, feels very strong.

Originally Posted by Glemm1970

There is no sense from the full E85 on this E40 firmware! You need 18 timing with a 21.5 boost from exactly 4500 to 6700 rpm. This is possible in custom firmware. But stok turbo this mode may not pull. Therefore, pour a maximum of E45 / 50. It makes no sense to load the pump.

There is sense for me. I know there isn't any measurable performance benefit from E40 to E85 with this map. I don't want to run a custom map and I'm happy with <7 sec 100 - 200 km/h and 10.9 sec quarter mile performance. I want to fill the tank with E85 for convenience and reduction in reliance on fossil fuel.

[kern417]

Originally Posted by OzBMR

Something must be wrong with your set up if you're randomly getting fuel pressure dips and backfires. I never get this. What are the other indicators that something is wrong?

STFT's up to 20% are fine, stop being dramatic. As long as the key logged values are OK I'm not worried. Running meth IMO is far riskier.

For comparison here's a log from July (cooler ambient temps) last year with the same map and E40 fuel mix. The STFT's are almost identical, as are all the other values, so I don't see what your concern is. https://datazap.me/u/ozbmr/ozbmr-mhd...24-25-26-27-28

It was during custom tuning when we were hitting the limits of the hpfp. As weather changes, etc. we adjusted the map to give more headroom. Because a log like yours can work fine in certain conditions until it doesn't in others.

The fuel trim limit is 30%. 20% is definitely not ok. That's why a safer tune would taper in boost around the fuel system's limits and dial in fueling better. Even if you have unlimited fuel headroom, high fuel trims can cause the car to lean out at the limit.

[OzBMR]

Originally Posted by kern417

It was during custom tuning when we were hitting the limits of the hpfp. As weather changes, etc. we adjusted the map to give more headroom. Because a log like yours can work fine in certain conditions until it doesn't in others.

The fuel trim limit is 30%. 20% is definitely not ok. That's why a safer tune would taper in boost around the fuel system's limits and dial in fueling better. Even if you have unlimited fuel headroom, high fuel trims can cause the car to lean out at the limit.

I think your problem was that you went cheapskate originally with the TU pump and tried to run straight E85 I understand now you've finally upgraded to Dorch Stage 2 as well.

As the fuel trim log data is practically identical using E85 and E40 with the Stage 2+ E40 map you are suggesting that MHD and BM3 are providing dangerous off the shelf maps to users? Comparing the two, STFT's in the spool up, both around +15 to +16 values at 2600 RPM and around +7 to +9 values at 4000 rpm. By 6000 RPM both STFT's are 0 for both E40 and E85.

[kern417]

Originally Posted by OzBMR

I think your problem was that you went cheapskate originally with the TU pump and tried to run straight E85 I understand now you've finally upgraded to Dorch Stage 2 as well.

As the fuel trim log data is practically identical using E85 and E40 with the Stage 2+ E40 map you are suggesting that MHD and BM3 are providing dangerous off the shelf maps to users? Comparing the two, STFT's in the spool up, both around +15 to +16 values at 2600 RPM and around +7 to +9 values at 4000 rpm. By 6000 RPM both STFT's are 0 for both E40 and E85.

You don't even want to go there lol.

I bought, installed, and tuned the TU pump before anyone else on the forums. There were NO HPFP options when I installed and tuned it on my car. I did the research, documented the entire process for the community, and then months later Dorch/Spool options came out along with the OTS stage 2+ maps.

I did a full review and even commented in my video that it isn't the best option for full E85. I have tried every pump option, tuned, and tested with an aftermarket turbo kit in varying blends and again documented the process and posted the results.

Going through multiple pumps, turbos, and tunes is not cheap. Testing on my personal car and posting the results to help others choose isn't cheap either. The only cheapskate choice would be after all those options and information became available, you still try to run 40+% more ethanol on an OTS map instead of getting a custom tune

And yes, fuel trims that high are dangerous. I've seen that targetting E40+ on an E30 map to see how it performed. Fuel trims are literally spiking when the pump is most sensitive. You should know that's why it's extremely rare to see rail pressure dips at high rpm vs the midrange.

YMMV, but you're deliberately eating into your safety net because it's convenient. Even if you have the fueling headroom, the DME can only adjust so much. Like I said, it works great until it doesn't. Good luck .

[foronoob]

Hi Guys, m240i f22 2021 , from Argentina, my target is 500hp aprox. with stock turbo, I think MHD stage2+ with e40 will be enought. What do you think?

Already have, catless downpipe, xhp st3, mhd 2 98ron, Dinan intake comming .

The question is Tu pump or DE St1 ?

thanks a lot

[T_H_O_M_A_S]

Originally Posted by foronoob

Hi Guys, m240i f22 2021 , from Argentina, my target is 500hp aprox. with stock turbo, I think MHD stage2+ with e40 will be enought. What do you think?

Already have, catless downpipe, xhp st3, mhd 2 98ron, Dinan intake comming .

The question is Tu pump or DE St1 ?

thanks a lot

to answer your questions .

Yes and the tu pump is enough

ive got 490 whp on that map setting .

[foronoob]

Originally Posted by T_H_O_M_A_S

to answer your questions .

Yes and the tu pump is enough

ive got 490 whp on that map setting .

Thanks!

[mike082802]

fuel it hpfp stage 1 and 2. from terry it seems they are the exact same pumps as dorch is selling.

https://burgertuning.com/products/fu...I0Z043TKfw4q7k

[mike082802]

fuel it hpfp stage 1 and 2. from terry it seems they are the exact same pumps as dorch is selling.

https://burgertuning.com/products/fu...I0Z043TKfw4q7k

[Glemm1970]

Originally Posted by mike082802

fuel it hpfp stage 1 and 2. from terry it seems they are the exact same pumps as dorch is selling.

https://burgertuning.com/products/fu...I0Z043TKfw4q7k

They say it's Bosch

[kern417]

I'll be discussing it in my video monday