The 1M does not have high flow cats or Larger Turbos

[T1M]

We've all heard this one. The 1M has high flow cats from factory, there's no need for aftermarket catless/high flow DP's etc. One member we all know and love even recently asserted the 1M has 200 cell downpipe cats. The same member has also been known to state that 1M turbos are larger. No evidence was ever provided in either case of course, just talk.

Refer to page 16 of the BMW 1M Techical Guide (found here: http://www.1addicts.com/forums/attac...2&d=1396203865) , outlining all the changes made on the 1M.

The excerpt:

4.1.4. Exhaust system

The design of the primary catalytic converters is the same as for the N54B30T0 on the BMW Z4sDrive35is except that the flange positioning is different. The catalytic converters are as on the 135i.

The front muffler has been modified for a more sports-type sound and optimized exhaust flow. The
rear muffler is a new design with four chrome tail pipes without controlled flaps.

It states clearly the catalysts are the same as the 135i.

In addition, there is no mention of larger turbochargers, or note of any differences in the turbochargers whatsoever. This makes sense given the 1M makes ~same power/torque as any 135/335 when tuned. If the turbo's were different, they'd have mentioned them in this technical guide, where all the other changes are noted.

As a final note, people should always refer to BMW technical guides for correct information, rather than listening to people on forums that like to perpetuate myths and talk a lot without backing any of it up with facts

[martymil]

Originally Posted by T1M

We've all heard this one. The 1M has high flow cats from factory, there's no need for aftermarket catless/high flow DP's etc. One member we all know and love even recently asserted the 1M has 200 cell downpipe cats. The same member has also been known to state that 1M turbos are larger. No evidence was ever provided in either case of course, just talk.

Refer to page 16 of the BMW 1M Techical Guide (found here: http://www.1addicts.com/forums/attac...2&d=1396203865) , outlining all the changes made on the 1M.

The excerpt:

4.1.4. Exhaust system

The design of the primary catalytic converters is the same as for the N54B30T0 on the BMW Z4sDrive35is except that the flange positioning is different. The catalytic converters are as on the 135i.

The front muffler has been modified for a more sports-type sound and optimized exhaust flow. The
rear muffler is a new design with four chrome tail pipes without controlled flaps.

It states clearly the catalysts are the same as the 135i.

In addition, there is no mention of larger turbochargers, or note of any differences in the turbochargers whatsoever. This makes sense given the 1M makes ~same power/torque as any 135/335 when tuned. If the turbo's were different, they'd have mentioned them in this technical guide, where all the other changes are noted.

As a final note, people should always refer to BMW technical guides for correct information, rather than listening to people on forums that like to perpetuate myths and talk a lot without backing any of it up with facts

You want to get into a debate here we go.

Because your wrong and your misinterpreting what you are reading

The primary cats are different to the 135 but same on all vehicles fitted with the n54b30t motor as in the 1m except the flanges on the z4 and z435is

When they refer to the catalytic converters they refer to the secondary ones and then they mention the front muffler which means the one after the cats which is welded up.

They dont mention any difference because when running stock boost it makes no difference but if you look at the part numbers between the original primary cats and the ones fitted to the 1m, z4 and z435is they are different

135i part numbers for primary cats

18307553594 and 18307553595

1m part numbers for primary cats

18307647042 and 18307647043

zr and z435is numbers for primary cats

18307647040 and 18307647041

So automatically you can disregard your findings and dont believe everything you
read from bmw is true

They make changes/improvements and they say nothing

Turbocharges

Here are the original part numbers and then they where superseded with the current ones, your wrong again

Dont believe everything bmw or real oem posts.

If you look at real oem they conveniently deleted the previous part numbers I wonder why

They don't do this for other parts.

[juld0zer]

Is it not just a matter of packaging? I have not had them out side by side.

ie. the cores are the same, just the piping, bends, indents, flanges and whatnot are adapted to suit the installation?

[martymil]

Just to clarify

The 135/335 came out with turbos 11654564710 & 11654564712

Then they got replaced with 11657583863 & 11657583865 to address the rattle

Around late 2010 or early 2011 they changed them to the larger 11657593015 & 11657593017
and that's what you get from bmw if you get warranty replacements or if you order some.

[titium]

Originally Posted by martymil

Around late 2010 or early 2011 they changed them to the larger 11657593015 & 11657593017
and that's what you get from bmw if you get warranty replacements or if you order some.

larger in what way? they're still td03-10kt turbos just like the first revision. being physically larger externally i can't see giving any significant performance advantage.

[martymil]

They changed the inlet size, its around 2mm bigger.

Externaly its exactly the same

Ill try and get some pics today

[martymil]

Originally Posted by juld0zer

Is it not just a matter of packaging? I have not had them out side by side.

ie. the cores are the same, just the piping, bends, indents, flanges and whatnot are adapted to suit the installation?

The turbos externally are exactly the same when it comes to physical size

The only visible difference is the inlet size and without dismantling the turbo
and knowing what to look for it would be impossible to tell

Yet the 135/335 with these original turbos has a very hard time sustaining
boost any higher that 17/18 psi where the 1m/z4/z4 35is does not and can
make boost right up to 25psi at redline but don't expect the turbos to last as
the shaft speeds are of the chart, I found the sweet spot to be around 19 to 20
and its still making substantial power gains, around 16 rwk more than previous.

[questionable]

Have you thought maybe the engine has different headwork ?

[martymil]

Ive seen a bulletin at one stage that there was small changes in the oil galleries
and the way they channel throught the head and extra cooling in the back of the
head but i cant confirm that

As i stated earlier i lost a lot of bmw paperwork when my laptop was stolen

They made small changes but never disclosed it to the public

The n54t is the last revision of the n54 and its the best they made before
switching over to the new n55 and s55

The port work is the same from what i was told by vac a few years back

[questionable]

AFAIK They run a completely different head. probably why they seem to make better power or hold it for longer, this makes more sence than trying to argue over a turbo charger.

[titium]

Originally Posted by martymil

Ive seen a bulletin at one stage that there was small changes in the oil galleries
and the way they channel throught the head and extra cooling in the back of the
head but i cant confirm that

As i stated earlier i lost a lot of bmw paperwork when my laptop was stolen

They made small changes but never disclosed it to the public

The n54t is the last revision of the n54 and its the best they made before
switching over to the new n55 and s55

The port work is the same from what i was told by vac a few years back

those changes are on every n54 that has the 6 bolt crank. not 1m specific. pretty sure it was coolant passages that were changed.

[martymil]

Well i know of one bloke in melbourne that bolted the 1m turbos or equivelent on a 135 or 335 and he makes 25psi tapering down to 22 to redline

If he wants to jump in he is welcome to

[martymil]

Originally Posted by titium

those changes are on every n54 that has the 6 bolt crank. not 1m specific. pretty sure it was coolant passages that were changed.

Changes are n54b30t specific

Not sure the n54 fitted with the six bolt is the same, would need to do a little research

[gmx]

Dude, just get some evidence like a picture of the "inlet" (compressor housing inlet??) with calipers.

[martymil]

Already on it.

I already have the measurements with verniers for the 1m/z4/z4 35is n54t just got to get the early build turbos done now.

Because I know part numbers are just not enough for some.

[T1M]

Part numbers don't tell you anything alone other than a new part supersedes an older part. Could be identical and just from a different supplier or a minor change. The suspicion is it was a wastegate rattle fix.

I'm not buying the slightly larger inlet snout suddenly making the turbos capable of holding numerous psi more. Look at how much power can be made from stock snout diameter turbos - it's not even close to being a limitation with the tiny oem compressors. Also just because it can doesn't mean you should. Holding 20psi at redline is not 'comfortable' for the turbos to do and should not be something folks go around recommending.

[Rob@RBTurbo]

OP is correct in that there is no difference in 1M turbos from any of the other N54s. Most of the "meaningful" changes in PN over the years were simply due to attempts at making the wastegates better.

Having tore apart at least 25 sets of 1M turbos over the years, rest assured they are nothing special.

Rob

[martymil]

Rob, I know there is a difference because I made a metal extension for my rear inlet to stop my rear inlet slipping off.

When I made another one for a 135 it didn't fit it was 1 to 2 mm smaller

Going to post pics as soon I get the measurements

When I tuned my mates 135 we can get it past 17.6 psi up top, 14k on the clock

Fitted a set of 1m turbos that were given to me holding 20 psi to redline.

I know its nothing special really its only 2.5 psi and 16rwk difference but it made him happy

[Rob@RBTurbo]

Originally Posted by martymil

Rob, I know there is a difference because I made a metal extension for my rear inlet to stop my rear inlet slipping off.

When I made another one for a 135 it didn't fit it was 1 to 2 mm smaller

Going to post pics as soon I get the measurements

When I tuned my mates 135 we can get it past 17.6 psi up top, 14k on the clock

Fitted a set of 1m turbos that were given to me holding 20 psi to redline.

I know its nothing special really its only 2.5 psi and 16rwk difference but it made him happy

We have only had to make one lathe fixture for all of the N54 compressor housings as they are all the same size (1.81" or 46mm). Guess worse case we can agree to disagree here.

Rob

[martymil]

Cant explain it then if the same, the one turbo I tried to make the extension for did not fit
so i never bothered making more, because of this as i didn't want people coming back to
say it doesnt fit

The problem with all rear turbos is the snout it too short to properly grip the silicone inlet

Yes you can get it on and make it stay on but its a major pain

ill get those pics up soon

[Rob@RBTurbo]

Originally Posted by martymil

Cant explain it then if the same, the one turbo I tried to make the extension for did not fit
so i never bothered making more, because of this as i didn't want people coming back to
say it doesnt fit

The problem with all rear turbos is the snout it too short to properly grip the silicone inlet

Yes you can get it on and make it stay on but its a major pain

ill get those pics up soon

The smaller length snout (without a lip) certainly doesn't help but there are other variables too such as trying to use a 2" ID inlet on the 1.81" OD snout... it just fits very loose/sloppy and is a very poor idea. Cheap hardware/clamps also could contribute to this sort of cause, although certainly secondary to getting a properly fitting inlet hose such as a 1.75" ID inlet.

Up until about 2 weeks ago we've never heard of an issue with our 1.75" inlets (at least not directly reported to us) but turns out the installer was using a lube on the mating surfaces. Once that was cleaned up no issues coming off. Don't use lubes either!

In short if you use the correct size, properly fitting inlets, with great quality hardware/clamps, and make sure the mating surfaces are clean and dry- you should not have any issues.

Thanks,
Rob

[martymil]

I never had issues with yours, but i only fitted one of your sets

The problem with the metal extension it was a loose fit on the rear turbo inlet
snout but it fit perfectly on the 1m turbo same measurments you provided

Thats why i didnt bother and ive seen another 1 or 2 set like that since then

I also found that if someone didnt run a bms catch can but had silicone inlets fitted it the breather from the flapper would lubricate the pipe and eventually come off