Anyone upgraded lpfp on the Z4

[Lambobimmer]

There are many people in the 3 and 1 Series that have done this and I was wondering if anyone on this board and tried this mod. SteveAZ sells a kit that he designs but the Z4 has a different setup than the 3 and 1 and it won't work.

I have been in contact with Steve and he might be able to help us out but he will probably want some interest.

The purpose of this mod it to be able to run higher concentrations of E85. The stock pump won't keep up and the fuel pressure will drop too much and that is why the lpfp is either replaced or an inline lpfp is used in conjunction with the stock pump.

Anyone have interest in this mod?

Using 50% E85 and 50% 93 will get your rwhp to around 450 on stock turbos with a proper tune.

[Ramjet]

I have been wanting to upgrade the LPFP for some time. Yes definitely have interest in a plug and play kit.

I have looked at the Z4 LPFP bucket and pulled the pump out and can confirm it is very different to the 3 and 1 series. Ours also has a more complex siphon system to draw fuel from the other side of the tank (look at realoem if this doesn't make sense to you), so if we don't keep this working properly then we technically halve our fuel carrying capacity.

The existing pump looks exactly like the Walbro 455 (same shape and size) so I do expect that the 455 will drop into the bucket without modification. The only issue is that the hoses are all molded, no clips on the pump bucket area, and you have to cut the hoses to change the pump out - no issue if you know how to connect fuel hoses properly (I'm not confident to do this yet due to reading about problems others have).

I'm interested in the in-line option, but again not sure if this will disrupt the tank siphon system. Technically, if we left the OEM pump in place the in line option could be plug and play, with the right clips - which are different to the 3 and 1 series.

I have a few meth flow issues to sort out first, once they are solved I was going to get back to the LPFP.

As I said, would be great for SteveAZ to come up with a plug and play for the Z4!

[Lambobimmer]

I looked at both of the pumps online and the Z4 looks very different. I agree that I would prefer an inline option rather than a pump replacement.

However, I am curious as to how long a new or almost new OEM pump assembly would last if you started running higher concentrations of E85. Will the OEM pump just not produce enough psi even if new or does it just wear out over time and lose psi.

If a new OEM pump will work for a period of a year or 2 then I would just consider replacing the OEM pump when it starts to lose psi.

[nicknaz]

Originally Posted by Lambobimmer

If a new OEM pump will work for a period of a year or 2 then I would just consider replacing the OEM pump when it starts to lose psi.

Is there a risk you would run very lean and cause some damage from detonation?

What about going with RB turbo + methanol injection kit rather than E85 ?

[Lambobimmer]

Originally Posted by nicknaz

Is there a risk you would run very lean and cause some damage from detonation?

What about going with RB turbo + methanol injection kit rather than E85 ?

If you have a proper tune than this is not an issue. PTF can handle this. I like the idea of using E85 because it is cheap. RB and Meth is going to be 5k+.

I am running E50 on the OTS Cobb map and it is crazy how much more power it makes.

[nicknaz]

Is e50 the "community consensus" on the highest concentration that is ok with the stock parts?

[Lambobimmer]

Originally Posted by nicknaz

Is e50 the "community consensus" on the highest concentration that is ok with the stock parts?

e50 is most common. LPFP is the weak link and higher amounts of e85 can be run if the LPFP can keep up. I am going to Dyno my car again on my PTF 50 map soon to compare to my PTF 93 map. I think that I will probably pick up 50hp and 50tq. It is really ridiculous how much more power my Z4 makes on E50.

[Drew@Sonic MS]

Just go with an inline 255, that's the best option right now until PTF releases their new products. For the price (~$150) nothing really to lose anyways.

It'll hold up just fine for the amount you're running, plus any more E85 would be useless in terms of power. There's "kits" with all the accessories you'll need on Ebay.

[Lambobimmer]

Originally Posted by Drew@Sonic MS

Just go with an inline 255, that's the best option right now until PTF releases their new products. For the price (~$150) nothing really to lose anyways.

It'll hold up just fine for the amount you're running, plus any more E85 would be useless in terms of power. There's "kits" with all the accessories you'll need on Ebay.

Supposedly the LPFP design on the Z4 is different from the 3 and 1 series. I am considering buying a used LPFP and seeing if I can make the 255 inline work. I guess that many of the DIY guides on the 3 forum will also work on the Z4 application. Any thoughts?

[dwspen01]

What fuel upgrades are people doing on the Z4 for stage 2 turbo upgrades? I haven't seen any lpfp options.

[dwspen01]

Has anyone tried installing the new DW400 lpfp in the E89 tank? It is supposed to flow 30%+ more fuel than Walbro 450, which doesn't flow enough for my stage 2 turbos.