[randyf32]

Hey guys, I have read so many mixed answers on this one i'm confused.

Can a F32 N55 run full E85 with a dorch stage 2 HPFP with a stock lpfp?

Thanks!

[thejeremyman9]

Well the answer is yes, the question is how much power/boost it will support; is that what you are asking?

[randyf32]

Originally Posted by thejeremyman9

Well the answer is yes, the question is how much power/boost it will support; is that what you are asking?

Correct should have asked the question better

[zole2112]

Originally Posted by randyf32

Hey guys, I have read so many mixed answers on this one i'm confused.

Can a F32 N55 run full E85 with a dorch stage 2 HPFP with a stock lpfp?

Thanks!

I'm wondering the same. Still on the fence on the Dorsch or PI. Multiple scenarios including full e85 as you mentioned. For me 650hp, I want to run at least e50 but I don't want to run on the edge of the HPFP capability either.

[thejeremyman9]

Originally Posted by zole2112

I'm wondering the same. Still on the fence on the Dorsch or PI. Multiple scenarios including full e85 as you mentioned. For me 650hp, I want to run at least e50 but I don't want to run on the edge of the HPFP capability either.

https://f30.bimmerpost.com/forums/sh...1723999&page=3

He ran over 600whp with E40-E50 but he did have meth on top i believe. According to dorsch website, they say 500whp on full E85. I think that's a safe/conservative estimate to leave you with a little more headroom on the HPFP so you dont get crashes if its cold outside or something. I am not aware of anyone here who has pushed over that with a dorsch stage 2 on full E85 so if you dead set on 600+ with full E85 you might be the one to test the limits. I also think that going to 600+ on full E85 might be at/beyond the limit of the LPFP as well.

Personally I think that if you want to go full E85, getting the stage 2 HPFP, keeping stock LPFP, and getting a nice safe tune for low 500s whp is the way to go... put less stress on everything, not worry about being at the limit of hardware, and keep engine/trans alive for a long time. Just my opinion though, your car and $$$

[n55david]

i have a dorch stage 2.. you can not run full e85 withouth the lpfp becoming a problem.

e70ish, yeah sure.

[thejeremyman9]

Originally Posted by Phantom10R

i have a dorch stage 2.. you can not run full e85 withouth the lpfp becoming a problem.

e70ish, yeah sure.

At what power/boost level? Because E85 would only have about 10-15% less energy density than E50, and LPFP has been pushed far on E50.

[randyf32]

Originally Posted by Phantom10R

i have a dorch stage 2.. you can not run full e85 withouth the lpfp becoming a problem.

e70ish, yeah sure.

Now I am lost, so if you run full E85 and make 475-500WHP will the LPFP cause issues or only bottleneck if you push further?

[thejeremyman9]

Originally Posted by randyf32

Now I am lost, so if you run full E85 and make 475-500WHP will the LPFP cause issues or only bottleneck if you push further?

Yeah i was a little confused by that statement as well lol, that's why i asked the question above. If one can make ~600whp with E50 on stock LPFP and stage 2 HPFP, you would think based on energy density of fuel going from E50 to E85 that you could make around 500whp with full E85...

I dont suppose anyone knows the lph rating of the OEM LPFP?

[n55david]

no idea.. im at like 20.1 psi

if i dont back off the ethanol to around e70 i will get a fuel pressure crash.. thats after multiple revisions and talking to dorch. seems the lpfp wont support a maxed maxed out system.

[thejeremyman9]

Originally Posted by Phantom10R

no idea.. im at like 20.1 psi

if i dont back off the ethanol to around e70 i will get a fuel pressure crash.. thats after multiple revisions and talking to dorch. seems the lpfp wont support a maxed maxed out system.

Interesting, good to know. I think you are the only person i am aware of currently trying to run full E85 without PI.

Do you have any datalogs of trying to run E85 or successfully running E70?

It's too bad we dont have a LPFP pressure sensor.

[n55david]

Originally Posted by thejeremyman9

Interesting, good to know. I think you are the only person i am aware of currently trying to run full E85 without PI.

Do you have any datalogs of trying to run E85 or successfully running E70?

It's too bad we dont have a LPFP pressure sensor.

https://www.bootmod3.net/log?id=5f2f...0b43455399493d

anything about 6k and thenboost drops hards. like 14 to 15psi.. oem turbo cant keep up. thats with no leaks and a turbosmart diverter. im shifting at 6k to 6200ish tops

[thejeremyman9]

Originally Posted by Phantom10R

https://www.bootmod3.net/log?id=5f2f...0b43455399493d

anything about 6k and thenboost drops hards. like 14 to 15psi.. oem turbo cant keep up. thats with no leaks and a turbosmart diverter. im shifting at 6k to 6200ish tops

Ah gotta love the ethanol timing! Log looks pretty good. It would be really interesting to see how much power this makes compared to a pump gas log with the same boost and less timing (a question we will probably never know the answer to, lol).

[n55david]

Originally Posted by thejeremyman9

Ah gotta love the ethanol timing! Log looks pretty good. It would be really interesting to see how much power this makes compared to a pump gas log with the same boost and less timing (a question we will probably never know the answer to, lol).

dragy was 11.85 at up to 117

best i did on e30 was 12.08 or .04 or something

[randyf32]

Well I don't mind getting a new LPFP. My worries are I heard stage 2 LPFPs causing issues with stock ekp module, to be specific they are fuel-it.. would a spool stage 2 still have this issue? or would just be going stage 3 with a hobbs switch be the best option?

[thejeremyman9]

Originally Posted by randyf32

Well I don't mind getting a new LPFP. My worries are I heard stage 2 LPFPs causing issues with stock ekp module, to be specific they are fuel-it.. would a spool stage 2 still have this issue? or would just be going stage 3 with a hobbs switch be the best option?

Generally yeah that tends to be an issue with upgraded LPFP. There is an upgraded EKP available. Forgot the company, but its $500-600 IIRC.

[randyf32]

Originally Posted by thejeremyman9

Generally yeah that tends to be an issue with upgraded LPFP. There is an upgraded EKP available. Forgot the company, but its $500-600 IIRC.

will all stage 2 pumps have this issue? I'd rather buy the stage 3 than buy a new EKP..what are the chances a stage 3 pump could fail with a hobbs?

[thejeremyman9]

Originally Posted by randyf32

will all stage 2 pumps have this issue? I'd rather buy the stage 3 than buy a new EKP..what are the chances a stage 3 pump could fail with a hobbs?

Wait what? Are you saying you want to get an even bigger LPFP? The issue is basically with the amount of power the LPFP can draw and overheating the EKP.

[randyf32]

Originally Posted by thejeremyman9

Wait what? Are you saying you want to get an even bigger LPFP? The issue is basically with the amount of power the LPFP can draw and overheating the EKP.

Stage 3 LPFP(fuel it) from my understanding is a OEM LPFP rebuilt to be fully e85 compatiable with a secondary pump so it takes no additional draw on the EKP unless above 15psi, The secondary pump activates with a hobbs switch at about 15psi. So secondary pump will only be active in WOT I assume. I think that will solve the EKP issue but I am just curious to know if that would be a viable long term solution?

[thejeremyman9]

Originally Posted by randyf32

Stage 3 LPFP(fuel it) from my understanding is a OEM LPFP rebuilt to be fully e85 compatiable with a secondary pump so it takes no additional draw on the EKP unless above 15psi, The secondary pump activates with a hobbs switch at about 15psi. So secondary pump will only be active in WOT I assume. I think that will solve the EKP issue but I am just curious to know if that would be a viable long term solution?

Ah understood. Was not aware of that option. I would inquire to fuel-it directly about that. It sounds like they designed it specifically to avoid the EKP issue. I don't see why it wouldnt be a long term solution. It was probably more designed for PI but should work with E85 and stage 2 HPFP as well.