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I want to first say I was going back and forth when I first purchased my F55 about getting the JCW tune upgrade but the high price tag with installation it just seemed crazy, and all the bluetooth issues and such, I scrapped it and just kept it stock. Now 2 years later, I am thinking of doing this all at once to hopefully go smoother and save on some labor if I cant do it myself. Which I could definitely not do on the JCW kit. I know there are less options with F55 so maybe someone has something I am missing.
I know the tune will boost performance and needed for CEL, but I guess my questions are the following. The Cat less DP will make performance a little better and change the sound. But do I really need the exhaust because is that going to do much but just change the sound. Also anyone running the Milltek with stock exhaust and what are your thoughts? Will no cat and Remus sport mode be too much, because that is getting close to straight pipe. Also any other different exhaust out there anyone would suggest for a F55?
Who manufactures a turbo that would be a good upgrade?
Nothing conclusive yet at this time on the turbo. We'll be testing the turbo and pistons upgrade in the near future. We just received some OEM-size forged pistons (custom made) as a drop-in replacement to the factory cast pistons.
So, how much boost do you think they can handle without compromising the con rods? Will they require a larger turbocharger? Just curious before I start scheming again.
So, how much boost do you think they can handle without compromising the con rods? Will they require a larger turbocharger? Just curious before I start scheming again.
We'll let you know when we reach that point Stay tuned
A couple things to note. The NM cat-back deletes the secondary cat. The remus sport does not replace the secondary cat. A catback is going to net you minimal gains. Just added noise. Theoretically the NM exhaust should gain you slightly more due to deleting the 2nd cat.
Another option if you just want more noise is you can go a frankenstein Milltek exhaust. Since Milltek does not have a f55 exhaust you can purchase the non-resonated front silencer replacement pipe and the oe downpipe to milltek exhaust adapter. You would need a reducer to clamp on the front milltek pipe with the stock exhaust. This would delete your secondary cat and resonator but retaining the stock rear muffler.
A downpipe will gain you some power with a tune vs a car with factory downpipe. The factory downpipe has a cat right off the turbo which hurts some flow as well as increased egt's. The Milltek downpipe is the best on the market currently. The catless version has an extended secondary o2 sensor bung. They claim it wont cause a CEL and I have not seen any reports of someone saying the catless downpipe in fact caused a cat efficiency code.
On stock turbo an intake is pretty much useless unless you just want more noise.
IMO your best bang for the buck power wise doing a downpipe, intercooler, and tune. Do all 3 at the same time so your car has to be tuned once and youre not paying $100 per tune adjustment for an added part.
It is crazy Mini went through all the work to put a magic eye on the bottom of their pistons, those things were all the rage in the 90's, I guess they are bringing them back. Thanks Mini for your attention to detail!!!
um… surprisingly little side skirt? I am not an engine designer but that seems like it might not be the best weight-strength trade off to make.
the piston skirt and design is no different design compared to previous and current forced induction bmw engines B and N family.
The B series engines are a modular design. Same bore and stroke etc. The b58 engine is proven to be able to handle north of 500+whp on stock internals once you get past the fueling limitations. The b58 piston looks essentially identical design to the b48 piston.
I am still waiting for an educated answer from Mike in regards to how and why he feels the piston is the weak point of the B46/48. Other than severe detonation causing the piston to crack BUT detonation can easily take out a forged piston as well.
Mike do you know more about the only known tuned b48 engine failure than we do?
the piston skirt and design is no different design compared to previous and current forced induction bmw engines B and N family.
The B series engines are a modular design. Same bore and stroke etc. The b58 engine is proven to be able to handle north of 500+whp on stock internals once you get past the fueling limitations. The b58 piston looks essentially identical design to the b48 piston.
I am still waiting for an educated answer from Mike in regards to how and why he feels the piston is the weak point of the B46/48. Other than severe detonation causing the piston to crack BUT detonation can easily take out a forged piston as well.
Mike do you know more about the only known tuned b48 engine failure than we do?
We are not mechanical engineers and can't speculate what the B46/B48 MINI engine can or can not do. All we can do is provide results once our testings are completed with our forged pistons.
We are not mechanical engineers and can't speculate what the B46/B48 MINI engine can or can not do. All we can do is provide results once our testings are completed with our forged pistons.
Why not test what is possible on stock internals before diving into replacing internals? Without knowing the limitations of the engine weather it be fueling, rods, pistons, etc why waste money building an engine?
04-15-2018, 11:57 PM
Stay tuned 
