Best engine to drop into e85 z4?

[wigwig]

So I’ve been struggling to diagnose a problem with the m54 that is in my z for a few months, and I’ve finally given up trying to fix it. It runs well when it’s warm outside, so my plan is to build up a new engine to swap into it this fall, but I’m unsure which one would be best. Ideally id like to find motor mounts and brackets and such that I can purchase online rather than designing them myself (although it seems it might come to that at this point in time), so does anyone know if there are kits out there for swapping it to a v8? Id also like to say I’m not looking for recommendations of selling the car and buying a new one, practicality isn’t necessarily the goal of this project, it’s more about getting the hands on experience for me.

[Steeler]

Never looked into an engine swap, but my first thoughts would be the computers compatibility.

Anything is possible if you throw enough money at it.

Having said that, there is well documented 2JZ swap on this forum.

[Our03z4]

If you can't figure out the issue with your car I wouldn't recommend an engine swap, that's going to be infinitely times harder and require a lot of trouble shooting. I would stick it out with what you already have. The M54 is very simple to work on and reliable.

[wigwig]

Originally Posted by Our03z4

If you can't figure out the issue with your car I wouldn't recommend an engine swap, that's going to be infinitely times harder and require a lot of trouble shooting. I would stick it out with what you already have. The M54 is very simple to work on and reliable.

The problem I’m having is making it unreliable lol. I’ve had it to almost a dozen different shops and none of them have any idea what’s wrong, other than the engine just doesn’t run in cold weather

[Huz-Z]

Originally Posted by wigwig

The problem I’m having is making it unreliable lol. I’ve had it to almost a dozen different shops and none of them have any idea what’s wrong, other than the engine just doesn’t run in cold weather

Another engine same type as you have now.

[Our03z4]

Originally Posted by wigwig

The problem I’m having is making it unreliable lol. I’ve had it to almost a dozen different shops and none of them have any idea what’s wrong, other than the engine just doesn’t run in cold weather

Have you done a cold cylinder pressure check? Just curious. I'm betting it's something electrical, that'd be my guess. I always tell everyone to replace your MAF connector, not the MAF itself but the actual male plug. Also never use an aftermarket MAF sensor. My car drove me nuts with codes, poor cold starts and idle (to the point you couldn't trust it) and hesitation. Saw someone on the UK forum complaining about the same thing and said it was the plug. After 2 years of my struggles I tried it ($25 kit from ECS Tuning) and my problem has been fixed for over a year. No one was able to figure my issue out either. Worth a shot if you haven't done it. It basically just shows up as erratic behavior on any diag computer so techs can't figure it out and also the cars computer can't figure out what's going on either.

[wigwig]

Originally Posted by Our03z4

Have you done a cold cylinder pressure check? Just curious. I'm betting it's something electrical, that'd be my guess. I always tell everyone to replace your MAF connector, not the MAF itself but the actual male plug. Also never use an aftermarket MAF sensor. My car drove me nuts with codes, poor cold starts and idle (to the point you couldn't trust it) and hesitation. Saw someone on the UK forum complaining about the same thing and said it was the plug. After 2 years of my struggles I tried it ($25 kit from ECS Tuning) and my problem has been fixed for over a year. No one was able to figure my issue out either. Worth a shot if you haven't done it. It basically just shows up as erratic behavior on any diag computer so techs can't figure it out and also the cars computer can't figure out what's going on either.

Hmm, that’s interesting, and seems like it would be worth a shot. Could you share a link to the kit?

[Our03z4]

Originally Posted by wigwig

Hmm, that’s interesting, and seems like it would be worth a shot. Could you share a link to the kit?

Sorry it's from FCP Euro not ECS. But here it is, good luck and please report back.

https://www.fcpeuro.com/products/bmw...-12527512935kt

[wigwig]

Originally Posted by Our03z4

Sorry it's from FCP Euro not ECS. But here it is, good luck and please report back.

https://www.fcpeuro.com/products/bmw...-12527512935kt

Ordered and arriving Friday, I’ll post updates next time I get a chance to start it in the cold

[Our03z4]

Originally Posted by wigwig

Ordered and arriving Friday, I’ll post updates next time I get a chance to start it in the cold

Excellent! Just make sure to take your time, the metal pin/wire holders are a little tricky but the whole thing should only take 30mins tops. It's critical that you get everything fully seated and tight, any looseness in the wires going to the pins and you'll have the same issue. They basically come loose over the years from vibration.