435i Performance Mods

[AB]

I’m getting a bit bored of of my 435i but can’t think of anything I’d replace it with.

It’s got a JB4 box which improved things a bit and it’s had one of the silencers removed in the exhaust so it sounds a bit better than standard.

Apparently running 340bhp but it’s not been proven so I remain sceptical.

How difficult would it be to get to 400bhp? It’s no longer the car I use daily and for work so I’d quite like to see what can be done.

Any ideas?

[b14]

With a better map it will do 400 reasonably easily. Beyond that you'll probably need some injectors and possibly bigger turbo.

[Caddyshack]

I know someone with 700 bhp in a 135 and the engine has not been opened, mainly a Borg Warner turbo swap, intercooler and new ECU plus exhaust. Similar engine as yours.

[AB]

[redacted]

[GregK2]

Sports cat downpipe, intercooler, map to suit

[Andy70]

the jb4 box set on map 5 will adjust the mapping of the car, so no need for a remap, every mod I done to my n54 335i made a massive difference, I done charge pipe, turbo intake pipes and larger intercooler all bits got cheap enough on ebay. I decided to keep the cats as i didn't want to put off any buyers if i ever wanted to sell it and an exhaust company said that sports cats weren't worth it for what ever reason but try researching that yourself to see what you come up with. mine must be putting out 400 horses for not much money really. I had a little burn up with a newish 140i not so long back and it was quite a walk over really. over the moon so far. I want to get rid of the jb4 and have a custom map as IMHO i may get more out of it as I'm not keen on generic maps, however its been a decent guide

[Caddyshack]

Andy70 said:

the jb4 box set on map 5 will adjust the mapping of the car, so no need for a remap, every mod I done to my n54 335i made a massive difference, I done charge pipe, turbo intake pipes and larger intercooler all bits got cheap enough on ebay. I decided to keep the cats as i didn't want to put off any buyers if i ever wanted to sell it and an exhaust company said that sports cats weren't worth it for what ever reason but try researching that yourself to see what you come up with. mine must be putting out 400 horses for not much money really. I had a little burn up with a newish 140i not so long back and it was quite a walk over really. over the moon so far. I want to get rid of the jb4 and have a custom map as IMHO i may get more out of it as I'm not keen on generic maps, however its been a decent guide

Yes, some sort of bespoke live map would be better, I am sure.