[MSport35TT]

Current set up is signature plus: Jb4G5 firmware 20D and BMS backend e85 TT map.

When I load the map the cobb read instructions that I should only run the map with e50 and currently I have e40 mix with 93 in their. Am I safe to go to 50/50 e85 and 93 with out a e85 walbro pump?

[tjnitsche]

You could Log what your lpfp and hpfp are at using the e40 mix then if everything looks ok bump it up to e50 and try again.

I just installed the back end flash but am also installing the walbro 455

[MSport35TT]

Originally Posted by tjnitsche

You could Log what your lpfp and hpfp are at using the e40 mix then if everything looks ok bump it up to e50 and try again.

I just installed the back end flash but am also installing the walbro 455

Talk to me about the 455...Are there different walbro one can go with? what is recommended and why did u choose the 455?

Also how is MPG affected?

[tjnitsche]

There are a couple different options outlined on n54tech. I believe the thread is called "upgraded fuel pump installed!" The main choice you have is to replace the stock lpfp with the walbro 455 unit (part number is on the other thread I referred to) or use an inline pump located after the stock lpfp. I personally chose to use the walbro 455 pump because my stock lpfp had never been replaced before and I assumed at 50k miles the inline pump would just be a bandaid.

As far as MPG go it will be worse as you increase the percentages of e85 you use but the pump itself does not decrease MPG. The walbro 455 is just able to sustain the necessary 70ish psi the low pressure fuel system needs to deliver better than the stock lpfp. this plays a big role when you have higher fueling demands due to high HP applications or high e85 concentrations.

Hope that helps, make sure to check out n54tech for all the details on the fuel pump DIY I don't want to waste space repeating all of the steps and info

[Stucks]

log the low pressure and if its still good on e50, you are good to go. if not, stick with e40 for now until you can get the inline fuel pump upgrade or the walboro in tank upgrade. I have the walboro in take upgrade and it works well.

[MSport35TT]

Thank you all!

[enrita]

U need to log. Every engine/ hardware is different

[tjnitsche]

Originally Posted by enrita

U need to log. Every engine/ hardware is different

+1

[MSport35TT]

Originally Posted by enrita

U need to log. Every engine/ hardware is different

to find out which e85 fuel pump will work? I have logged for use and safety of motor already.

[enrita]

no to check if the pressure drops. on stock pump E40 is the max. The pump is the Walbro E85 455 or something. there is only one marked E85.