3.0t Low pressure fuel pump upgrade - help me figure this out please

[Hofahome]

Alright so I am admittedly a bit over my head here but hopefully this may help some people in the future. I need help in figuring some issues out. Bear with me...

First of all, from looking at the B8 S4 fuse diagram, the fuel pump draws max of 25 amps (is this the pump only???). I am not sure of the max pump flow of the stock pump - does someone have this info? A good upgrade looks to be this:

http://walbrofuelpumps.com/450lph-wa...f90000267.html

Oddly enough, it would only draw a max of 14 amps per their website, so I don't think (correct me if I am wrong) you would need to upgrade the electrical draw to the pump. (From what I have read, this is required for the 2.0t in the A3/TT if going over about 400hp since the factory fuel pump control module overheats when upgrading to a high-flow lpfp due to the added current draw)

HOWEVER, if the electrical draw does need to be upgraded for a high-flow lpfp OR you want to run something like a KB boost-a-pump on the stock lpfp, I may have found a good option. I looks well engineered and you can even buy a VAG plug-and-play adapter:

https://torqbyte.com/products/torqby...ant=6827435393


OK, so assuming the VAG adapter works with our car and you are able to fit the upgraded pump in place of the stock lpfp - which nobody knows a this time, how would you wire the pump? When looking at the stock lpfp assembly pics from ECS, I am kinda confused:

https://www.ecstuning.com/Audi-B8_S4...ump/ES2541336/


What are the yellow and brown wires that run to the pump? I can't find this info. I know our pump is PWM, but looking at the torqbyte it says it maintains full pwm control and although the pump is from a TTRS, the pics don't show the extra wires.


To further complicate things, I wonder if this would be the best option as it acts more like a piggyback than pump replacement.

http://www.uspmotorsports.com/Engine...el-System.html



Ok sorry to vomit all of my thoughts and questions. Please help with suggestions and any info that may be helpful. Thanks.

[Loe]

since you already have a HPFP upgrade, have you considered a simple inline booster pump? It's cheap to find universally as well and effective as it has enabled many N54 guys to go above E40-E45 mixtures to E60-E65 mixtures with it:

http://www.burgertuning.com/fuel_pump_upgrades_bmw.html

Walbro 255 inline pump (you can find it as cheap as $65 online elsewhere)

http://walbrofuelpumps.com/walbro-gs...ine-fuel-pumps

The 255 isn't rated for E85, however when combined with the N54's LPFP/HPFP, it was enough that they can run elevated E85 mixtures and in some cases full E85. I thought about going this route soon so that I don't run into any issues/complications to continue running my 37.7% (or possibly even higher) mixtures in colder climates with my 194mm crank.

[theswoleguy]

I wonder if the FFV A4 pump flows more. In theory it should and not as grumpy from corn and also drop right in.

Also some walbros are also pwm compatible. The E85 pump by them is and couple adapters to make them inline just as low said know a bunch of 335/535 guys that do silly things with corn and those pumps.

Sent from my Nexus 6P using Google's ProjectFI

[Ze_Nardo6]

sub'd

[AudBoost]

I thought about tackling this project when I had some free time but looking at the design of the OEM LPFP bucket it looks like it will be more involved than the LPFP setup on my 335. Maybe we could seek from guidance from Steve over at http://www.fuel-it.biz/. He is the one that pioneered the LPFP upgrade for the N54 ad N55 BMW's.

[613B6]

I've used the torqbyte PM3 and PM5 on my MK5 with a TTRS pump to make 520whp and still had room left. The solutions works amazing, you should give Alex a shout first as it might be all you need for the extra fueling at this point.

[Hofahome]

I've used the torqbyte PM3 and PM5 on my MK5 with a TTRS pump to make 520whp and still had room left. The solutions works amazing, you should give Alex a shout first as it might be all you need for the extra fueling at this point.

Ya that thing looks legit. The problem is that I don't know what the stock pump can handle and dont want to mess with upgrading the pump (like you did on the mk5) if I dont have to. I would like to keep it simple and just need enough flow for maybe 100hp over stock.

[Hofahome]

Found this over lunch: $350 on amazon

http://fuelab.com/products/performan...line_fuel_pump

[KnewJack]

A Bosch 044 fuel pump outflows walbro 255HP @12v and works well with E85. May be another good inline solution.