[MrBones93]

So I was just watching Farah's most recent one take with VIVID Racing's CLA45 AMG (ECU flash, exhaust, coil overs, and brakes) and all of a sudden it struck me... how come this 2.0 4cyl can crank out 425hp with essentially just a tune, yet our 3.0 6cyl can only approach ~375hp with a tune only?? Is it the difference between a true ECU flash and a piggy back?? The Golf R is another 2 liter 4 cyl that can break 400hp yet here we are stuck well under that ceiling. If I am completely off basis/missing something obvious, edumucate me plz.

Title edit: putting out** more power... woops

[JMatt88]

Higher boost on turbo = more stress on engine = shorter engine life.

I'm curious to see how the MB holds up over 5 years. I saw one review that said the MB transmission was lacking. The VW is interesting but also lacking in driveability. I think the BMW affords you the whole package with decent longevity.If you choose to boost the N55 to the moon and or change it's mapping, it's your call.


Still looking for a Position at a BMW Dealership as a Service Advisor or Genius... willing to relocate (east or west coast).




.

[1LegitM235i]

Well said JMatt! Superior driveability is BMW's foundation. Current technology can boost horsepower all day long by any car company these days, but without the driver's feedback/influence in mind. All that power to me is a fizzle without the pleasure of controlling it.

I haven't driven a CLA45, but from what I've seen and heard, you're not well connected with the car steering/tranny wise. Just point the steering to the direction you want to go and hit the gas.

[Cyberdemon]

There are 2.0L engines that have been putting out 500+hp for over a decade, just look at what the tuning scene had done with the Nissan SR20DET and the Mitsu 4G63.

There are also N54 and N55 engines that are putting down 450+whp.

The N54 was generally regarded as the engine with "more" potential, but as many N54 owners can attest to it was not the most reliable of engines. The N55 scaled back power in exchange for reliability.

The CLA45 is still very new to the scene with a new powerplant, so it certainly is an impressive little beast, but how it holds up in the long run will remain to be seen.

Reliability aside, high strung turbo engines drive much differently than larger displacement turbo engines. You need to decide where to tune an engine and where to put boost based on the tune and turbo design. Most new cars optimize for low end torque, whereas many of the big HP motors will have gross turbo lag and than a massive surge of power (RE: anything from the 90's).

Point being there are a lot of things you can do with the engine, and there are a lot of elements in the system that have to be able to support those additional power loads besides the engine. The fact that your engine makes 500hp will mean nothing if it grenades the transmission, twists the driveshafts, or overpowers the entire cooling system.

I had a highly tuned NA Corvette (~525hp LS1 up from 350hp) and I can tell you that every time I chased more power something else went wrong. Got tired of chasing numbers only to have the car in the shop every 2 weeks.

[slider86]

I can't really recall any performance or //M car in recent history having more power than their Audi and MB equivalents (think E92 M3 vs. RS5 and C63 AMG). It's always been more about handling characteristics and driveability.

Think about it this way - one of the reasons why there's so little lag (if any) in the N55 units is because BMW has mated a reasonably-sized turbo w/ moderate boost to a 6-cyl engine. To me, it feels like they're trying to retain the driveability of the buttery-smooth NA engines from the previous generation, while trying to provide a substantial bump in performance.

[scrape1]

The answer is fairly straight forward. Not all 2.0 turbo motors are created equal. The EA888 in the golf R and the M133 in the AMG have more robust blocks, heads, and and internals than the N20. They can handle more boost and higher torque. Same goes for the Mitsu 4B11T.

It's getting to be fairly well documented that without internal upgrades, the N20 can only handle a mild tune without suffering a pretty fast catastrophic failure. So far I have seen talk of cracked heads when pushed past 330 lb/ft wtq. Melted pistons. Failed rods.

Some people will call it BMW cheaping out on blocks and engine internals. Some people will say BMW is being perfectly reasonable in building an engine that can reliably handle stock power levels, but not much more. Fact remains that N20 engines do not handle the power levels that a few other engines on the market can. It looks like the B48 might be even worse, if it proves true that it's running 11:1 compression.

[BarryJI]

Originally Posted by scrape1

It's getting to be fairly well documented that without internal upgrades, the N20 can only handle a mild tune without suffering a pretty fast catastrophic failure. So far I have seen talk of cracked heads when pushed past 330 lb/ft wtq. Melted pistons. Failed rods.

Interesting. Dinan Stage 1 for my 228i (N26) gives a peak 327 lb/ft (vs. 260 lb/ft stock) so if the magic number is 330, I will not hold my breath for a Stage 2!

[Cyberdemon]

Originally Posted by BarryJI

Interesting. Dinan Stage 1 for my 228i (N26) gives a peak 327 lb/ft (vs. 260 lb/ft stock) so if the magic number is 330, I will not hold my breath for a Stage 2!

That's crank HP, not WheelHP.

If you look at most dyno's the N20 and N55 are underrated from the factory, and the N20 produces nearly it's crank HP numbers at the wheels, which means to BMW's credit the engine is stronger than listed on paper.

Ultimately you can fudge around with HP numbers a lot, and if you are looking for pure HP numbers alone there are certainly better cars to buy than BMW's, no doubt about that.

[scrape1]

Originally Posted by BarryJI

Interesting. Dinan Stage 1 for my 228i (N26) gives a peak 327 lb/ft (vs. 260 lb/ft stock) so if the magic number is 330, I will not hold my breath for a Stage 2!

Pretty sure Dinan publishes crank torque, not wheel torque, and their figures seem to come from an advertising friendly dyno. But yeah, I have a Dinan stage one on my N20, and I personally would be worried about pushing it any harder without some internal upgrades.

[2msport]

Originally Posted by BarryJI

Interesting. Dinan Stage 1 for my 228i (N26) gives a peak 327 lb/ft (vs. 260 lb/ft stock) so if the magic number is 330, I will not hold my breath for a Stage 2!

260 lbs at the wheels.
327 lbs at the crank.

The stock n20 is about 300 ftlbs at the crank.

You gained 27ftlbs. Not 70.

I know this is besides your point for this thread but there is a difference.

[MrBones93]

Man, do I love learning! I assumed the MB block was far more robust and had far higher boost. I also have heard that their tranny is pretty iffy. One thing I do want to clear up is that in no way am I complaining about my BMW or BMW's in general. I agree with the few people that mentioned BMW isn't about numbers but about complete balance. I understand that, with all kinds of work, we can easily get 450hp out of the N55 but based on how Matt Farah described the mods on the CLA45 AMG, I was moreso trying to compare base tune to base tune, if that makes sense. I am definitely in the balanced reliability boat rather than the numbers, numbers, numbers boat.

[2msport]

Originally Posted by MrBones93

Man, do I love learning! I assumed the MB block was far more robust and had far higher boost. I also have heard that their tranny is pretty iffy. One thing I do want to clear up is that in no way am I complaining about my BMW or BMW's in general. I agree with the few people that mentioned BMW isn't about numbers but about complete balance. I understand that, with all kinds of work, we can easily get 450hp out of the N55 but based on how Matt Farah described the mods on the CLA45 AMG, I was moreso trying to compare base tune to base tune, if that makes sense. I am definitely in the balanced reliability boat rather than the numbers, numbers, numbers boat.

If you're comparing base tune to base tune, and the MB starts out with higher hp then it will end up with higher numbers after the tune. (Which is what you were asking in the OP) Also important. An ECU tune will give higher gains than a stage 1 piggyback. Far superior tune at that...

EDIT: the Benz do run higher boost but are also reinforced to account it.

[Cyberdemon]

Tunes are also dependent on the rest of the system, not just the computer.

If the engine, intake, exhaust, turbo, fuel system and cooling can all handle more boost it is easy to throw that boost at it and get a lot more power from a tune.

Generally as people tune they hit a wall somewhere, which is why most stage 2-3+ kits include replaced intakes, exhausts, and meth injection, along with maps for higher octane fuel which allows people to further push the engines & HP numbers.

[nike001]

All other things aside, that little 2L engine (apparently) runs a compression ratio of 8.6:1 and peaks at 26.1lbs of boost.

Our N55's run 10.2:1 compression with what, 7-10lbs of boost? That's very low boost IMO. The 2006 330i had 255hp from a very similar NATURALLY ASPIRATED engine. So a turbo only getting you ~16% more horsepower isn't a lot at all.

You can build any engine for higher or lower compression with different boost pressures and be anywhere on the power spectrum as you want. BMW just did theirs differently than MB. Apples-Oranges.

[2msport]

Originally Posted by nike001

All other things aside, that little 2L engine (apparently) runs a compression ratio of 8.6:1 and peaks at 26.1lbs of boost.

Our N55's run 10.2:1 compression with what, 7-10lbs of boost? That's very low boost IMO. The 2006 330i had 255hp from a very similar NATURALLY ASPIRATED engine. So a turbo only getting you ~16% more horsepower isn't a lot at all.

You can build any engine for higher or lower compression with different boost pressures and be anywhere on the power spectrum as you want. BMW just did theirs differently than MB. Apples-Oranges.

I agree with you except you can't ignore torque. World's more than that 330 at a lower rpm.

[Outrun]

With the never-ending horsepower wars between non-exotic car manufacturers, for the average consumer at what number of horsepower will we cross the line from "fun and powerful' over to "stupid dangerous and complete overkill" ?????

I've never driven a vehicle with more HP than my 235, and it's got gobs of power....I can only imagine what a 400+ engine is like....

[Cyberdemon]

Originally Posted by nike001

Our N55's run 10.2:1 compression with what, 7-10lbs of boost? That's very low boost IMO. The 2006 330i had 255hp from a very similar NATURALLY ASPIRATED engine. So a turbo only getting you ~16% more horsepower isn't a lot at all.

Sorry not sure how you got those numbers? If you are totally stock you're comparing 255hp to 325hp. That's a 28% gain, 18% if you're comparing the older 300hp quoted N55 tune (which was also underrated. Ignoring manufacturers numbers for a second:

Looking at most dynos the 330 actually dynos at the crank an optimistic ~210hp/200ft lbs even with a tune.

The stock M235i tune of the N55 shows about ~310hp/325 ft/lbs.

Thats a 100hp/125ft/lb delta, 48% more HP, 62% more torque. That's substantial.

[den525]

Ummm it's because of the size of the turbo!!! 2l with a big turbo vs 3l with a twin scroll mini turbo.

It's like a small dose of steroids on a big man vs a big dose of steroids on a small man

[nike001]

Originally Posted by Cyberdemon

Sorry not sure how you got those numbers? If you are totally stock you're comparing 255hp to 325hp. That's a 28% gain, 18% if you're comparing the older 300hp quoted N55 tune (which was also underrated. Ignoring manufacturers numbers for a second:

Looking at most dynos the 330 actually dynos at the crank an optimistic ~210hp/200ft lbs even with a tune.

The stock M235i tune of the N55 shows about ~310hp/325 ft/lbs.

Thats a 100hp/125ft/lb delta, 48% more HP, 62% more torque. That's substantial.

I was quoting 300hp as the 'normal' N55 35i engine output, because that's the engine that's compared against most, tuned the most, advertised the most etc. I bet most people don't even know what the PPK is, nonetheless that our 235i's come with one from the factory.

Also, I'm not sure what 330i you're talking about.. since my E46 330i ZHP dyno'd 205whp/218tq at the wheels with only a BMW Performance intake & fresh VANOS rebuild. Figuring BMW 'rated' (because rating and actual are usually different, as we've all found out) the E90 330i at 255hp, It's safe to assume they dyno around ~220whp (and a quick google search proved me mostly correct) and you can use whichever drivetrain % loss you'd like to figure crank power.

But with all of that aside, taking BMW as THEY rate cars.. 255hp to 300hp isn't all that much for a turbo. MPPK & tuning aside.

None of that matters though. The point I was trying to make is that BMW turbo'd an already pretty powerful engine for decent gains, and MB turbo'd a tiny 2.0L for fantastic gains... both landing them on about the same 'stock' playing field.

[Cpdbeemer]

I am sure a big part of the reason BMW whacked the turbo on was for the torque. Power is only half the story. Look at the torque output and more importantly the torque curve. That is where the big gain has been made, and the big impact on the way these cars drive.

[Nahlem]

I kinda miss my old T5 engine from the Volvo 2,5 liter 5 cylinder engine that could be tuned like crazy without costing you a fortune to do so. It wasn't the prettiest sounding of them all but it could take a beating that is for sure. The small mods on the picture bellow including full replacement of the stock exhaust system with 3 inch all the way from the turbo to the back with a race catalyst. And a small APC plug in box. It Delivered around 300-310 bhp had 220 from the start that's a 90 bhp gain for less then 3500€

And this was the standard you did on this engines pretty much then you could tune it up to 420-450 bhp and the engine would still stand the beating. The big replacement then was the turbo needed to be replaced. Even after all that it still maybe costed you a maximum of 7000€.

Thats my only problem with BMW they charge a bit to much for parts and tuning for these cars imo.

Thats the same engine as ford used in Focus RS MKII and Focus RS 500 probably one of the best engines made in history when it comes to reliability.

[CalCarNut]

You can't compare a purpose built MB AMG 2.0L to the stock 2.0L in the BMWs. The internals as previously mentioned are built bullet proof with forged cranks, stronger rods, etc. to survive 355hp levels. If BMW decided to make an M versioned 2L you can bet it'd handle the power also.