[lukechristy]

Just yesterday I took my stock fuel bucket out and replaced the pump with a Walbro 450 from Racetronix and also modified the bucket so it acts as a bucket-less system. Cranked the car up and it idled normally. Took the car for a drive a noticed that when I go on throttle above 2500 rpm that I get major fuel starvation. I pulled up my MHD on my phone and started monitoring and noticed that the lpfp psi is normal at about 75-80 psi at idle and normal driving. However when I get on throttle the psi drops pretty fast getting as low as 20 psi. The ECU threw a 2AAF code which I suspected. Pulled the pump out today and checked the wiring and connection to the fuel hoses. Rewire the pump just to make sure and put the assembly back in the fuel tank to go test. Still noticed the drop in psi on low pressure side but didn't get the sudden jerk like the car fell on its face. Could I possible have gotten a bad pump, is my epk fried, is the bucket-less system pron to this kind of failure? Any input would help a lot.

BTW stock pump worked perfectly fine, no fuel starvation issues before upgrade.

I will get data logs tomorrow and upload them on this thread.

07 335i- FBO (-inlets), spec stage 3+ clutch

[iqraceworks]

How much fuel is in your tank??

Have you ran any logs showing the fuel pressure dropping off?

[lukechristy]

Originally Posted by iqraceworks

How much fuel is in your tank??

Have you ran any logs showing the fuel pressure dropping off?

Tank is just over 3/4 full of fuel. Haven't looked at the logs yet but in the monitoring part of the app I can look at the values live. Low pressure psi dropped fast as soon as I started to make any boost at all(right around 2800-3200 rmp).

[IllSic_Design]

Why did you make it bucket-less? Bucketed is for sure better, bucket-less can cause starvation issues under certain circumstances

[iqraceworks]

Originally Posted by IllSic_Design

Why did you make it bucket-less? Bucketed is for sure better, bucket-less can cause starvation issues under certain circumstances

Maybe if you are under 1/4 tank and taking long and hard corners at the track...but other than that, you can run your tank about dry and still be able to get enough fuel if you are just straight line drag racing......also, bucketless usually gives you aroumd 20% more fuel volume vs. bucketed....so there are definitely some benefits.

[lukechristy]

Originally Posted by IllSic_Design

Why did you make it bucket-less? Bucketed is for sure better, bucket-less can cause starvation issues under certain circumstances

Bucket-less is way cheaper if you do it yourself. A Fuel-It kit is $350-500 bucks. Including the pump and fittings, it only cost me 120 bucks to go bucket-less. Im 17 and don't have tons of money to throw at the car. Also it seems like a lot of people have gone DIY bucketless and and no issues.

[iqraceworks]

Originally Posted by lukechristy

Bucket-less is way cheaper if you do it yourself. A Fuel-It kit is $350-500 bucks. Including the pump and fittings, it only cost me 120 bucks to go bucket-less. Im 17 and don't have tons of money to throw at the car. Also it seems like a lot of people have gone DIY bucketless and and no issues.

On a side note.....if you are 17 and broke, a 335i is about the worst car you could have. Unreliable compared to other cars....and a total Maintenance hog.

How long have you had your 335i??

[IllSic_Design]

Originally Posted by iqraceworks

Maybe if you are under 1/4 tank and taking long and hard corners at the track...but other than that, you can run your tank about dry and still be able to get enough fuel if you are just straight line drag racing......also, bucketless usually gives you aroumd 20% more fuel volume vs. bucketed....so there are definitely some benefits.

Notice I said certain circumstances..........

It is well recommended to go bucketed on this platform, I don't care about any small benefits if it comes at the cost/risk of fuel starvation.

You can DIY a bucketed setup for about the same as bucketless...

Unless he got a faulty pump, there's not really much that could go wrong with putting in the AFT pump. Unless maybe you start messing with the system, like cutting open/off the bucket/valve/whatever else is in the OEM bucketed system.

[lukechristy]

Originally Posted by iqraceworks

On a side note.....if you are 17 and broke, a 335i is about the worst car you could have. Unreliable compared to other cars....and a total Maintenance hog.

How long have you had your 335i??

Had it for a year now, only really had to replace HPFP. not saying im broke just figured if I could save 350 bucks on this I could just spend that on a bucket seat or something.

[iqraceworks]

Originally Posted by IllSic_Design

Notice I said certain circumstances..........

It is well recommended to go bucketed on this platform, I don't care about any small benefits if it comes at the cost/risk of fuel starvation.

You can DIY a bucketed setup for about the same as bucketless...

Unless he got a faulty pump, there's not really much that could go wrong with putting in the AFT pump. Unless maybe you start messing with the system, like cutting open/off the bucket/valve/whatever else is in the OEM bucketed system.

The only benefit of a bucketed pump is that you so you don't have to deal with fuel starvation during long sweeping turns when you have 1/4 tank or less of fuel. That's the only benefit.

If you aren't going to be tracking the car and/or you can keep over 1/4 fuel in the tank, a Bucketless setup is the way to go. 20%+ more fuel volume with the same pump!!

I'm running Bucketless and have never had any issues, even under 1/4 tank fuel taking hard corners and a tune than requires plenty of fuel. I'm glad I went bucketless.....when your Bucketed Walbro 450 can't flow enough fuel and you have to upgrade to two pumps, my Bucketless Walbro 450 still has plenty of fuel to keep things running.

[IllSic_Design]

Originally Posted by lukechristy

Bucket-less is way cheaper if you do it yourself. A Fuel-It kit is $350-500 bucks. Including the pump and fittings, it only cost me 120 bucks to go bucket-less. Im 17 and don't have tons of money to throw at the car. Also it seems like a lot of people have gone DIY bucketless and and no issues.

I said DIY, not buying a kit;

How would this be much more expensive then your bucketless setup?
https://www.1addicts.com/forums/show....php?t=1428292

There's like 2-3 fittings and some hose added onto the cost of the pump you purchased.

[iqraceworks]

DIY Bucketed or Bucketless is basically the same price....but if you are drag racing and never tracking your car, the Bucketless setup flows 20% more fuel with the same Walbro 450 pump....that's huge!!

Now if you are one of those few people that actually tracks their car......and runs them very low on fuel at the track (not many people)...you would be better off with a Bucketed setup since it feeds more fuel to the pump when the fuel level in the tank is extremely low.

When you are talking 20% more fuel flow....that's basically 20% more power. You are basically talking about giving up 100hp for the benefit of being able to take hard corners with an empty fuel tank. I'd rather have the 20% extra fuel from a Bucketless system.

[Luis561]

Originally Posted by iqraceworks

DIY Bucketed or Bucketless is basically the same price....but if you are drag racing and never tracking your car, the Bucketless setup flows 20% more fuel with the same Walbro 450 pump....that's huge!!

Now if you are one of those few people that actually tracks their car......and runs them very low on fuel at the track (not many people)...you would be better off with a Bucketed setup since it feeds more fuel to the pump when the fuel level in the tank is extremely low.

When you are talking 20% more fuel flow....that's basically 20% more power. You are basically talking about giving up 100hp for the benefit of being able to take hard corners with an empty fuel tank. I'd rather have the 20% extra fuel from a Bucketless system.

There's only a $20 difference between diy bucket and bucketless. Bucket only requires one more hose and an adapter to connect that hose to the Venturi

[mweisdorfer]

Originally Posted by lukechristy

Bucket-less is way cheaper if you do it yourself. A Fuel-It kit is $350-500 bucks. Including the pump and fittings, it only cost me 120 bucks to go bucket-less. Im 17 and don't have tons of money to throw at the car. Also it seems like a lot of people have gone DIY bucketless and and no issues.

You can do a Bucketed walboro 450 for maybe 150-75 in a DIY

[Emilime75]

Originally Posted by iqraceworks

...the Bucketless setup flows 20% more fuel with the same Walbro 450 pump...

How? Why?

Originally Posted by iqraceworks

...When you are talking 20% more fuel flow....that's basically 20% more power. You are basically talking about giving up 100hp...

You sure about that? Where did those numbers come from?

[stewbets]

Originally Posted by lukechristy

Bucket-less is way cheaper if you do it yourself. A Fuel-It kit is $350-500 bucks. Including the pump and fittings, it only cost me 120 bucks to go bucket-less. Im 17 and don't have tons of money to throw at the car. Also it seems like a lot of people have gone DIY bucketless and and no issues.

Don't worry about all the bucketless naysayers. It's a proven mod. Bucketless is not your problem. Definitely get a log as soon as possible and upload it to datazap.me. That should be your automatic go-to with these sorts of issues. And I don't know anything about Racetronix, but I do know there are lots of Walbro fakes out there.

[iqraceworks]

With a Bucketed setup, you have to use the oem Venturi fitting that mounts to the bottom of the bucket to suck fuel from the tank into the bucket. All of that fuel that flows through the Venturi in order to make it work, is fuel that isn't making it's way down the fuel line to the motor. The Venturi takes volume away from the pump output.

With a Bucketless setup, the bottom of the bucket is cut out to allow fuel to reach the pump.....no Venturi fitting needed, and no fuel slow wasted to run the Venturi.....so 100% of the pump output goes to the motor.


I was wrong on the numbers though....you lose around 10% fuel flow (.2 GPM) using a bucket with the Venturi. That's still a big gain that most people could take advantage of if they never are going to be tracking their car.

Check out BMP's site...lots of bucket/bucketless info there.

[C.Pop]

If you made your setup bucketless and you're getting 20psi of lpfp as soon as you have real fuel demand, then your setup is done incorrectly, your pump is broken, or you are starving the walbro of fuel somehow. Post pics of what you did.

[NoGuru]

I drag race with a basketless and have had zero issues. This can be debated forever.

Where did you source the pump from? Amazon has lots of counterfeit Walbros.

[Emilime75]

The counterfeit pump question is worth considering, but highly doubtful if it did come from Racetronix. Could be defective, though.

Possible to be an install error. Either a fuel line or the intake filter are pinched, allowing enough flow for low demand. Possibly a failing EKP that can't drive the higher current draw of the new pump - could possibly measure that with a DMM and/or a clamp meter for voltage/amperage. See if the EKP is getting really hot, too.

[iqraceworks]

Got any pictures on how you plumbed in your new 450 pump? Maybe you had a kinked line? Or something to that affect?

[lukechristy]

Originally Posted by Emilime75

The counterfeit pump question is worth considering, but highly doubtful if it did come from Racetronix. Could be defective, though.

Possible to be an install error. Either a fuel line or the intake filter are pinched, allowing enough flow for low demand. Possibly a failing EKP that can't drive the higher current draw of the new pump - could possibly measure that with a DMM and/or a clamp meter for voltage/amperage. See if the EKP is getting really hot, too.

The fuel filter was a really tight fit onto the walbro 450, could that be the issue? I double checked that all the lines were fitted correctly on the fittings. I can take some pictures momentarily. How do I measure the voltage from the EKP module and where is that located?