- Mar 6, 2023
And hello to everyone on Spoolstreet. My beloved 335i n54 has come to the point of 100k miles and it's time to move on from twins. I'm planning to move to Doc Races bottom mount single turbo kit with 6266 gen 1. I try split my typing into segments, so I can explain everything I will do as well as I can and can bring up questions that I still need answers for. My only experience with single turbo engines has been on 1998 Volvo s40 T4 @420hp, so n54 platform is kinda new thing for me. EVERY single advice is welcome.
I will also follow the used amount of money on the project. If someone else from Europe wants to do a similar build, they can have an idea of the amount of money needed.
Setup at the moment:
- 335i E90 2007
- Stock turbos
- Cone intakes
- 5.5" stepped intercooler
- MHD stage 2+
I have come up with a plan that I try to follow so I can collect all the parts and make sure everything will work when I actually start changing the parts. This way I can avoid waiting and delays on my project. I also happen to live on are where getting parts isn't fast at all.
- DOC Race DR700 with 6266 gen 1
- Stage 2+ or stage 3 LPFP
- Reusing the 5.5" intercooler. Should be enough flow and cooling since I live in Finland where weather is always chilly. ($500)
- Upgraded charge pipe with 50mm tial BOV
- Controlling everything with MHD
The plan:My plan is to upgrade every single needed support mod for the vehicle to be ready for the single turbo kit. I will also do the maintenance to make sure everything is ready for the big power. Already ordered charge pipe and BOV ($600 with shipping and tax) and I'm looking into buying the LPFP ($600 with shipping and tax). I will install those mods and make sure they work before moving on the bigger mods.
I will be using the DR700 kit because I want the factory look and Finnish vehicle inspection can be really strict. I'm probably going with the 6266 gen 1 because I believe it's a good value for the money and the amount of air it can move is good for my power range (Correct me if I'm wrong). I'm also going with recycled dump. This kit will run me for $3500, but the cost to ship the whole package to Finland is not going to be cheap. $400 for shipping and around $600 for import taxes. Keep this in mind if you are ordering these parts to Europe. ATM I'm looking into other options for shipping. There are smaller companies that will bring your parts to Europe via ship container and will cost a lot less, but will take a lot more time.
I would like to control everything using MHD. Since they released the multi map support and boost solenoid control for single turbo setups. I believe controlling the boost with MAC solenoid ($100 with shipping and tax) should work by doing this mod on ECU (video):
Boost control with MHD
I haven't decided if I will go with local tuner or use for US tuner, for example Motiv. Also I haven't decided if I will run e85 or 98oct or mixture.
The questions:Like on every single new project, there are questions. Here are couple of them.
Can the job be done without dropping the subframe? Doc race kit says so but I'm little sceptical about that. I have a tiny little plan how I could do the whole job from the above without dropping the frame, but we will see.
How is the stock ignition system? Can the stock ignition coils handle these mods fine. I just changed a fresh set of original ones and I would like to use them. Also, what spark plugs should I run?
Should I just control everything with MHD? I have seen people using external boost controllers to run different amount of boost and I was hoping to do this with MHD multi map function. Is this the best way to go or should I consider something else?
Conclusion:Did I forget about something important? Is there a better way to do this? Tell me your wisdom.
Thank you in advance for every advice I will get.