335i N54 twin turbo to single conversion

[Joey_87]

Has anyone done the single turbo conversion on their 335i?

[Elliot2000]

Why would u want too?

[Joey_87]

I’m just looking into it as I’ve seen people do that and get a lot out of it but I’m still new to this and I’m just putting the feelers out there, just researching for now

[Andy70]

Elliot2000 said:

Why would u want too?

I am aware of this being done, but agreed, why would you want to? ii have a 335i, so I'll be watching this closely

[survivalist]

Andy70 said:

Elliot2000 said:

Why would u want too?

I am aware of this being done, but agreed, why would you want to? ii have a 335i, so I'll be watching this closely

The usual reason is big power, seems to be very popular in the USA. OP doesn't state what tuning he's already done, but for a usable road car a remap along with upgrades to the downpipes, intercooler, intake, exhaust and charge pipe should see very decent gains. Going single turbo is a different league in terms of cost, commitment and (potentially) usability.

[4rephill]

I suspect it's done because it's easier to tune a single turbo for bigger power gains than it is the twin turbo's, due to having to keep the twin turbo's in sync with each other.

I also suspect it gives a big thump of power all in one go, making the driver feel like Vin diesel hitting the nitrous in The Fast And The Furious films, whereas the twin turbo's spread the power boost over a wider range, feeling less powerful.

I can't help thinking though that that big thump of instant power comes at a price - Big turbo lag as the turbo has to spool up (the very reason why BMW went with twin turbo's - Less lag)

TBH, it sounds to me as though the OP has read about massive power gains from a single turbo set up, has figured it's an easy to do - bolt on job, that is all pro's and no con's.

I'd suggest the OP carries out more research into the idea before committing any serious money into it.

[aeropilot]

Joey_87 said:

Has anyone done the single turbo conversion on their 335i?

Don't know if anyone on here has, but there are a few N54 single turbo conversions in UK, from back when I used to frequent the forums when I had my 135i.
Chuffin expensive thing to do though.........!!!!

[Dannbodge]

There are a couple of people running single turbo kits now.

More so on the 3fiver facebook group than forums.

The biggest issue is plumbing and space. They generally have to go top mount and have some very tricky piping to fit around the steering column.

[Silverbullet767]

If your car is standard already, a better bet would be to do a remap. A JB4, or MHD remap can be had for a fraction of the cost.

For instance my car is running a JB4 and has dyno'd at 375bhp. Should be all the power you'll need on our greasy roads.

[CousinDupree]

Here's one somebody made earlier. These N54s really are becoming the next big power inline six. The closed deck S55 must have even more potential.

https://www.youtube.com/watch?v=HWvIoYm6CJI

830 WHP BMW 335i Runway Racer - One Take

[Honestherbert]

A big single if fitted and mapped properly will come on song as quick if not quicker than the twins and be able to make more power more reliably. The only downside is cost. The N54 is an awesome engine and ripe for tuning, I have seen a few 600bhp+ singles in the uk but mainly 1 series iirc. Have a google who are doing them in the uk as I cant remember,the reason they are compared to the 2jz is their ability to make big power quite easily with bolt ons....iirc the fuelling system is up to it without much modification, just a bigger pump for example. As for feeling like vin diesel some people like to feel the hit of a turbo! If I wanted smooth power all the way through to the redline you would have brought an N/A.