[Ruster82]

Hi all I have got a I have got a 2006 335i and I am in the UK so need to stick to emission laws so I am curious how much power can the N54 make with cats still installed?

[Pavlo335]

For stock dps i have heard you can make around 360hp any more than that is risky there is just too much restriction on the exhaust flow for that much boost

[nicky dj]

If you have Ethanol and a FMIC you can get up 400hp Stage1+

[Saif2018]

Originally Posted by Pavlo335

For stock dps i have heard you can make around 360hp any more than that is risky there is just too much restriction on the exhaust flow for that much boost

That's about stage 1 power, which MHD states on their website.

Your saying that going Stage 1+ with fmic is too risky?

[Pavlo335]

Originally Posted by Saif2018

That's about stage 1 power, which MHD states on their website.

Your saying that going Stage 1+ with fmic is too risky?

That really depends who’s asking the question. My 335 is my daily driver and I don’t want to be shelling out the money to replace the turbos any time soon so yes, for me personally I would play it safe and not go more than stage 1 without fmic + dps at the minimum. I’m sure there are plenty of people that would be fine going stage 1+ with just fmic but i like to stay on the safe side.

[CarAbuser]

No problems using the stage2+ map on a car with cats in my opinion. I did that for 4 years.

I only kept them in place for warranty reasons, once the warranty was up I removed them and have passed 2 MOTs in that time. You don't need primary cats to pass emissions checks if the car is in good health.

[CALWATERBOY]

Originally Posted by Ruster82

Hi all I have got a I have got a 2006 335i and I am in the UK so need to stick to emission laws so I am curious how much power can the N54 make with cats still installed?

460 hp; similar ft lb torque. What you'll need, and will seriously appreciate, is alcohol & water injection w/chip to make it work.

JB4 can do that. Working outside the design envelope, you should consider stronger parts such as piston rods.

You play, you pay! The good thing about JB4 is....can go back to stock map w/couple o'button pushes, steering wheel. Almost instant. Can prevent unauthorized operation w/code.

[Saif2018]

Originally Posted by Pavlo335

That really depends who’s asking the question. My 335 is my daily driver and I don’t want to be shelling out the money to replace the turbos any time soon so yes, for me personally I would play it safe and not go more than stage 1 without fmic + dps at the minimum. I’m sure there are plenty of people that would be fine going stage 1+ with just fmic but i like to stay on the safe side.

I wouldn't run Stage 1+ without FMIC,

Stage 1+ with FMIC, should be ok though.

Downpipes+ FMIC is recommended for Stage 2+ by MHD

The ots maps are Conservative, so I'm not so worried about Turbos going.

There's always a risk with tuning, if I was that concerned about Turbos going, I wouldn't tune at all.

[Saif2018]

Originally Posted by CarAbuser

No problems using the stage2+ map on a car with cats in my opinion. I did that for 4 years.

I only kept them in place for warranty reasons, once the warranty was up I removed them and have passed 2 MOTs in that time. You don't need primary cats to pass emissions checks if the car is in good health.

That's good to hear,

Does Hi flow cats pass emissions in UK?

[_N54]

I have the MHD Stage 1+ running E50, BMP Stage 2 LPFP, DCI, and 5" intercooler. It pretty damn quick and fun to drive. I have down-pipes, but don't plan on installing them anytime soon.

[Saif2018]

Originally Posted by ///S58

I have the MHD Stage 1+ running E50, BMP Stage 2 LPFP, DCI, and 5" intercooler. It pretty damn quick and fun to drive. I have down-pipes, but don't plan on installing them anytime soon.

I'd say that's perfect for daily

[CarAbuser]

Originally Posted by Saif2018

That's good to hear,

Does Hi flow cats pass emissions in UK?

Yes

[Saif2018]

Originally Posted by CarAbuser

Yes