New Tuner Here! Seeking Advice!!

[JMD]

Greetings all,....check this, I'm old to BMWs,...but new to this new age of BMW tuning. That is, with JB4s,...MHD, etc. I currently have a 2010 535xi Sport for DD duties, and recently got the "Tune Bug",....so, I threw a tune on it. The car is 'stock' other than the tune. That said, I'm quite happy with the results based on dollars spent, but wanted to know of additional possibilities. I like the rush the 'tune' provides,..but it's more like a jet engine rush with no exhaust note! The tune I have states some 360Hp, etc.

So, my questions are: 1) Is it possible to gain some 400,..450,..500Hp from the N54 from a tune that doesn't include removing the Cats?

The reason I ask, is because I live in a State that requires emission testing every 2 years and dam if I want to remove/install downpipes for passing emissions, etc.

2) Is it possible for higher Hp gains on just 91, 92, 93 octane fuel,..without e85?

Unlike the E90 335's,....which can easily take a larger FMIC,...the available aftermarket FMICs for the 535 appear to only be slightly larger than the stock unit,..at least from the pics I've seen online.

So, Naturally, more power for a turbocharged engine means more Boost! More Boost requires more Fuel,...and a proper Tune matched to the mechanicals of the engine, etc. That said,

3) Will larger Turbos be required,...if so, who makes a decent upgraded turbo kit,...4)Higher flowing HPFP,.....5)Larger injectors!

Note, in case you're wondering why I'm wanting to trick out my 535xi is because I don't see where anyone out there is doing so,......and I'm sure it may be because of available mods for 2WD cards vs X Drive model cars. My car is an autobox, so I'm sure there is a limit on the amount of Hp/Torque it can handle,...just as there is for a Manual tranny car,...before requiring an upgraded clutch.

Another reason for the 535xi is GRIP! Note, there is a reason BMW added "AWD" to the new F90 M5!,...and also the Nissan GTR is "AWD",...as well as many other hyped-up super cars!

Naturally, if high Hp was my only end game,...I could do one of the following,...pickup a worthy E60 M5,....(..but lose AWD capability,...which is nearly a must for Northern VA winters,...and wet/slippery conditions) or migrate to an E90 Coupe/Sedan!

Here are some things I definitely don't want,...I don't care for the "ratty" sound from a BMW setup,....note, I'm not knocking anyone else's build,...I'm just stating that the "ratty" sound is the character I don't want. Plus, I want to be able to past emissions,..all day,..every day!

Any advice would be greatly appreciated!

JMD,....on that East Coast!

[sloweste9x]

Well you could, but it's not great for the turbos, and that's coming from the guy who ran OEM down pipes the entire time on his 500hp FBO E92. I would've strongly suggested cat-less downpipes a year ago, but with many states adopting very strict recently inspection guidelines, running catless just got a lot harder, even with a variety of the sketchy "downpipes fixes" on the market.

I am building a 500hp N54 powered wagon right now, and I am buying high flow catted AR design downpipes. Sometimes with high flow aftermarket cats, the SES will still turn on as the cats aren't doing nearly enough work as the OEM ones, but I have heard nothing but good things for the AR design down pipes.

You can't make over 500whp on 93, and 500whp on 93 requires a single turbo or very large twins (Pure Stage 2s). With aftermarket TD03 frame turbos, you should be seeing 400-500hp on 93. I wouldn't waste any time on 91 unless that's all you have access to, in which case supplemental fueling becomes much more appealing.

I'm not really sure what you're asking on this last question. However I will say that all of these hybrid turbo kits are prone to failure, as by nature of the design of these incredibly small and high output turbos. The internal waste gate is another mechanism prone to failing. I am also an E6X guy, with my wagon, and I will say if you want to do this now, you should be looking at Pure Stage 2s, they have the most consistent reviews, the most consistent numbers, and are backed more shops than any other option.

If you want to wait a bit more, I know a certain company is working on a bottom mount twin scroll kit for the E6X chassis. This will likely be a much more robust upgrade over hybrids, however with no information on it, we're likely all be in the dark for a while.

All of the other modifications depend on your horsepower goals, anything over 500hp will need supplemental high pressure fueling, how you choose to do that is your call, but I would recommend port injection and a low pressure fuel upgrade is required to make any power over 400-420ish. Check out Fuel It for their E60 lpfp.


I've been working on these n54 cars for years now, and have done everything from intakes to pulling engines. A word of advice: most people on these forums are rude, entitled, and short tempered- try not to take it seriously. Not everyone here is patient when it comes to answering questions. Good luck on your build and if you have any questions just ask! Always love to see other E6X guys!

[JMD]

Originally Posted by mb21111

Well you could, but it's not great for the turbos, and that's coming from the guy who ran OEM down pipes the entire time on his 500hp FBO E92. I would've strongly suggested cat-less downpipes a year ago, but with many states adopting very strict recently inspection guidelines, running catless just got a lot harder, even with a variety of the sketchy "downpipes fixes" on the market.

I am building a 500hp N54 powered wagon right now, and I am buying high flow catted AR design downpipes. Sometimes with high flow aftermarket cats, the SES will still turn on as the cats aren't doing nearly enough work as the OEM ones, but I have heard nothing but good things for the AR design down pipes.

You can't make over 500whp on 93, and 500whp on 93 requires a single turbo or very large twins (Pure Stage 2s). With aftermarket TD03 frame turbos, you should be seeing 400-500hp on 93. I wouldn't waste any time on 91 unless that's all you have access to, in which case supplemental fueling becomes much more appealing.

I'm not really sure what you're asking on this last question. However I will say that all of these hybrid turbo kits are prone to failure, as by nature of the design of these incredibly small and high output turbos. The internal waste gate is another mechanism prone to failing. I am also an E6X guy, with my wagon, and I will say if you want to do this now, you should be looking at Pure Stage 2s, they have the most consistent reviews, the most consistent numbers, and are backed more shops than any other option.

If you want to wait a bit more, I know a certain company is working on a bottom mount twin scroll kit for the E6X chassis. This will likely be a much more robust upgrade over hybrids, however with no information on it, we're likely all be in the dark for a while.

All of the other modifications depend on your horsepower goals, anything over 500hp will need supplemental high pressure fueling, how you choose to do that is your call, but I would recommend port injection and a low pressure fuel upgrade is required to make any power over 400-420ish. Check out Fuel It for their E60 lpfp.


I've been working on these n54 cars for years now, and have done everything from intakes to pulling engines. A word of advice: most people on these forums are rude, entitled, and short tempered- try not to take it seriously. Not everyone here is patient when it comes to answering questions. Good luck on your build and if you have any questions just ask! Always love to see other E6X guys!

Thank you vm for your reply and excellent information. I will keep everything in mind.

Cheers,...

JMD