M54B30 Intake manifold

[Southernboy]

New M54 intake cam arrived today. All the bearing surfaces and lobes are good. Vernier shows all are 47.7mm from underside to tip of the lobe. The biggest visible difference is in the cam profile. The overall shape is less V and more "egg" shape. This is what provides the longer "open" position to the valves.
Stopped off at my BMW mechanic buddy earlier, and he is happy for me to do the swap at his workshop. Also, he has all the Vanos timing tools etc which I'll need doing the re-assembly.
Most comforting is to have him there to provide advice and guidance !!
So, hopefully, I'll have a day free next week to do the job...

 

[Southernboy]

Here's the big question.
Other than the manifold to cylinder head runner port mismatch, what other benefit does the M54 manifold provide?
If it's just the above, I would think it will be as easy to have the stock manifold runner ports machined to fit the cylinder head ports.
At least easier in terms of having the OEM throttle body mounting, and I gather from other forums that "it is imperative to do a re-tune since the ECU doesn't cope too well with the change, and in fact one may lose power" - Has anyone experience in this area??

Here's a comment from Iceman on Bimmerforums " I had headers, a mechanical fan delete, and the intake manifold swap, and I was no faster than my friends Z3 (same year, same engine) that was completely stock. The car FELT better, but didn't perform any better."
Iceman was referring to his E46 M52TU 2.8.

If anyone can provide any verifiable information on any other benefit the M54 IM provides it would be welcomed.

 

[Southernboy]

A very interesting read. I hope it goes well.

I am considering getting my 3.0 Throttle body enlarged and seeing what else can be done subtly for a few extra BHP.

I posted a few pages of interesting info in the "Performance" section a few days back. They are worth a read since they provide a clear understanding of which areas to look at when considering improvements in performance, as well as understanding how the improved performance is achieved. If you read through those pages, you might find the direction you want and should look into.

I must add, there was one line in the article which although obvious, quite startled me - It was to do with the movement of a piston inside the cylinder. The comment made was that "at speed, the piston moves from over 100 mph to zero in the space of somewhat equal to the width of your fist." Considering the length of the stroke of our pistons (80 something mm) it is quite startling to actually imagine !! And it does this 1000's of times in a minute...
Anyhow - go read the post and decide.

 

[gookah]

Here's the big question.
Other than the manifold to cylinder head runner port mismatch, what other benefit does the M54 manifold provide?
If it's just the above, I would think it will be as easy to have the stock manifold runner ports machined to fit the cylinder head ports.
At least easier in terms of having the OEM throttle body mounting, and I gather from other forums that "it is imperative to do a re-tune since the ECU doesn't cope too well with the change, and in fact one may lose power" - Has anyone experience in this area??

Here's a comment from Iceman on Bimmerforums " I had headers, a mechanical fan delete, and the intake manifold swap, and I was no faster than my friends Z3 (same year, same engine) that was completely stock. The car FELT better, but didn't perform any better."
Iceman was referring to his E46 M52TU 2.8.

If anyone can provide any verifiable information on any other benefit the M54 IM provides it would be welcomed.

I have already detailed this earlier in the thread, that you have disregarded. IT IS NOT JUST THE SHAPE OF THE PORTS...!!!!
The DISA sizes, the shorter tubes, the porting, there are 3 different manifolds for the tu engines
however you didn't agree that it would make any difference, and you still don't believe it will.
Why not just try it, instead of disregarding the difference myself and everyone else that has actually done it has experienced

The best way to be an expert in this is from experience, not opinion, it is not imperative to do a tune to see benefits. More than half a second off my quarter mile time without a tune and just swapping the manifold.

You have done pages and pages of what you think, time that could have been spent actually fitting it instead of determining it can't possibly have worked for anyone.
Read what Ant said in post 31 he gives figures, read what G8JKA said he gives figures,,
Like I said sell it to someone who will benefit,

why on earth did you buy it in the first place, then look for every answer you can, to back up that it wont work, you must have obviously read that it does make a difference to buy it, so what has now changed?

I give up, there seems to be no point, carry on talking yourself out of it

 

[Southernboy]

I have already detailed this earlier in the thread, that you have disregarded. IT IS NOT JUST THE SHAPE OF THE PORTS...!!!!
The DISA sizes, the shorter tubes, the porting, there are 3 different manifolds for the tu engines
however you didn't agree that it would make any difference, and you still don't believe it will.
Why not just try it, instead of disregarding the difference myself and everyone else that has actually done it has experienced

The best way to be an expert in this is from experience, not opinion, it is not imperative to do a tune to see benefits. More than half a second off my quarter mile time without a tune and just swapping the manifold.

You have done pages and pages of what you think, time that could have been spent actually fitting it instead of determining it can't possibly have worked for anyone.
Read what Ant said in post 31 he gives figures, read what G8JKA said he gives figures,,
Like I said sell it to someone who will benefit,

why on earth did you buy it in the first place, then look for every answer you can, to back up that it wont work, you must have obviously read that it does make a difference to buy it, so what has now changed?

I give up, there seems to be no point, carry on talking yourself out of it

 

[Southernboy]

Your comments are acknowledged, and you are correct that the only way to prove the benefit of the mod is to implement it myself.
I am not however trying to talk myself out of it. I am posing questions in the hope that someone will tell me how and why it does work.
My reading on various forums about the mod is confusing. In some instances there is, like your comments, a positive perception. Others have commented that there is little difference at low RPM, but that over 3500 rpm there is a lot of difference. Still other comments claim no difference. I note one member here is driving a car that had the OEM manifold runners machined, and he claims to be impressed with the performance of the car. So my questions are valid. If by simply machining the OEM manifold I gain 15hp instead of 18hp as has been suggested by G8JKA, then I would prefer to retain the OEM manifold. If it only makes 5hp, then I would prefer to change to the M54 manifold.
So my questions are not a matter of "belief", but of my own lack of understanding of the how, why and what it is that the M54 manifold does.
A larger DISA does what ? Shorter runners do what ? Does the air passing through the relatively small M52TU throttle body lose velocity when it enters the larger M54 manifold ? Does the fact that the size of M52 throttle body restrict the air flow such that the larger DISA and shorter runners compensate for that restriction.
You see, unless you actually get more air into the cylinder, there can't be a performance gain, and that can only happen if the air is forced in or the valves stay open longer for the air to get in. So, the question of airflow velocity through the throttle body into the larger M54 manifold vs the same velocity of air into the OEM manifold is a valid query. Perhaps it's a dumb question, but I haven't had an answer to it which even explains why it's a dumb question...
Sorry gookah, but I always ask questions, and once I understand as much as there is to understand, I can make an informed decision.

 

[gookah]

and that is exactly the effect....

Little difference at low revs, but BIG difference at high revs.... Why? because the DISA opens at high revs. Bigger DISA.....bigger effect, the shape of the ports are not the main effect. Like I said on page 1 ......... DISA DISA DISA...
You cannot put a bigger DISA in the other manifolds,
You fit the different manifold for the bigger DISA. this allows more air at higher revs, and the bigger it is the more effect it will have.

Shorter tubes means there is less effect of drag from the sides of the tubes.
Look up Bernoulli Effect and Boyles Law of Gases, Too many years as a mining engineer, where air flow rates and pressure drop in mine roadways had to be taken into account..... same effect.
I did a thermodynamics HND, adiabatic expansions, isentropic flow, specific enthalpy, etc etc, I wish I could remember it all now though......

 

[Southernboy]

Thanks.....
So The DISA is essentially a resonance control unit...
You might recall this from your studies...

Race tuners know there is a specific length from the carb mouth to the intake valve that produces the best power at a specific RPM. For racing, you can change this by just changing the velocity stack!

For the street, you have to compromise. The short Weber manifolds most kits have work just fine with the approximately 3" high velocity stacks in the same kit. For variable RPM road racing, a 1.6 engine redlined at 6000 needs about a 16" runner length, meaning the total measurement from carb mouth to intake valve.

Shorter runners lengths give more power at high RPMs, longer lengths give more power at lower RPMs.

When an engine is running, the downward motion of the piston during the intake stroke creates engine vacuum that draws the air-fuel mixture into the cylinder. However, as we’ve just noted, the intake valve is closed more often than it’s open. If the incoming mixture reaches the valve at a point when the valve is closed, the leading edge of the onrushing mixture will stop abruptly as it hits the closed valve, building up pressure that eventually forces the mixture back up the intake runner. When this pressurized air hits the opposite end of the runner, it reverses direction and heads back toward the valve. This sets up an oscillating pressure wave moving within the intake runner at the speed of sound (which in air varies considerably depending on atmospheric pressure, humidity, and ambient temperature, but is approximately 1,115–1,132 feet per second or 340–345 meters per second at sea level on a balmy spring day.)

If the valve is open when this newly pressurized intake air reaches that end of the runner, the mixture will be forced into the cylinder at higher-than-atmospheric pressure, just as if the engine were using a mechanical supercharger. As with a turbocharger or a supercharger, this supercharging effect — called resonance supercharging — allows more air and fuel to be packed into the cylinder, producing more power.

Naturally, resonance supercharging only provides a benefit at the points where the compressed mixture reaches the intake valve at a point where the valve is open for business. [...] Therefore, the supercharging only occurs part of the time, at certain engine speeds.

What engine speeds, you say? That depends on the frequency of the pressure wave. If you stayed awake in high school physics, you may dimly recall that the frequency of a wave is inversely proportional to its wavelength (that is, a short wavelength means a high frequency and vice versa). In this case, the wavelength is determined by the length of the space in which the pressure wave can move, i.e., the length of the intake runner. All else being equal, the longer the runner, the lower the engine speed at which resonance supercharging occurs and vice versa.

 

[Southernboy]

So, decision has been made.
Considering my post above regarding the runner length and the effect it has on low and high rpm performance, one must consider one's "general" driving behaviour. Since I'm not a race driver, or concerned about high speed at top end, it seems appropriate to do the machining of the OEM manifold. This will still maintain the low rpm performance, provide a little better airflow once the IM ports match the cylinder head, and negate the question of an non-centered TB. ( The jury is still out on a non centered TB. I have presented the question to a couple of speed freaks who like gookah are into racing performance. (one fella has a 1000hp Z3 2.8).

The deciding factor is the point made in my post above regarding the resonance wave and the fact that it should ultimately arrive at the intake valve when the valve is open and under greatest pressure. Given that BMW chose to make an intake manifold with runners x cm long, with a throttle body y mm large to realise the best resonance with the OEM DISA fitted, it seems common sense that by machining the runners to optimise the OEM manifold airflow, and replacing the OEM intake cam for the M54 cam, a potentially very satisfactory result is to be expected.

Here are the specs for intake and exhaust cams for M52TU and M54B30 respectively. As you will see the M54 intake vs M52TU intake varies in lift, and also degrees of open duration allowing a larger and longer open position for air to be drawn into the cylinders.

M52B28TU - in 228*, 9.0mm; exh 244*, 9.0mm

M54B30 - in 240*, 9.7mm, exh 244*, 9.0mm

Machining the OEM IM may not achieve as much top end performance as the M54 IM, but I'm looking to the intake cam to provide across the board improvement at low and high rpm. And hopefully those resonance waves will find more time to slip past the valves and into the cylinders to create extra torque and HP at 6000 ft above sea level..

 

[gookah]

So, decision has been made.
Considering my post above regarding the runner length and the effect it has on low and high rpm performance, one must consider one's "general" driving behaviour. Since I'm not a race driver, or concerned about high speed at top end, it seems appropriate to do the machining of the OEM manifold. This will still maintain the low rpm performance, provide a little better airflow once the IM ports match the cylinder head, and negate the question of an non-centered TB. ( The jury is still out on a non centered TB. I have presented the question to a couple of speed freaks who like gookah are into racing performance. (one fella has a 1000hp Z3 2.8).

The deciding factor is the point made in my post above regarding the resonance wave and the fact that it should ultimately arrive at the intake valve when the valve is open and under greatest pressure. Given that BMW chose to make an intake manifold with runners x cm long, with a throttle body y mm large to realise the best resonance with the OEM DISA fitted, it seems common sense that by machining the runners to optimise the OEM manifold airflow, and replacing the OEM intake cam for the M54 cam, a potentially very satisfactory result is to be expected.

Here are the specs for intake and exhaust cams for M52TU and M54B30 respectively. As you will see the M54 intake vs M52TU intake varies in lift, and also degrees of open duration allowing a larger and longer open position for air to be drawn into the cylinders.

M52B28TU - in 228*, 9.0mm; exh 244*, 9.0mm

M54B30 - in 240*, 9.7mm, exh 244*, 9.0mm

Machining the OEM IM may not achieve as much top end performance as the M54 IM, but I'm looking to the intake cam to provide across the board improvement at low and high rpm. And hopefully those resonance waves will find more time to slip past the valves and into the cylinders to create extra torque and HP at 6000 ft above sea level..

So you are deciding to keep the original manifold with the small DISA and just machine the ports?

so which part of "it's the larger DISA that makes the biggest difference, not the shape of the ports" did you not understand ?

Perhaps me saying DISA DISA DISA, was a couple of DISA's short.. Look at Ant's photo of the two DISA's, though I feel that everything I and others have written or shown photo's of, you have chosen to ignore.

By the way I am not a racing driver, nor is Ant, nor is g8jka, nor is Perfectjake, nor everyone else that has done this and been very happy with the improvement.
I quoted my quarter time to show the difference it has made, and the difference is not "top end" its from 4000 rpm onwards which we all dip into to overtake..

You say you were not trying to talk yourself out of it, then you could have just done it days ago, in the time it has taken to research and post thousands of words of this rubbish, and guess what , you still have to remove and refit the old one to do what you are doing anyway, which (and I wont be surprised), will come back with a "well like I thought, there doesn't seem to be much difference."


The only reason I keep replying to this, is because I don't want you talking others out of doing this valuable modification by using your 'research', and not letting them see the actual improvement the rest of us have seen.

Anyone who has searched for a post on this modification and arrived here, please speak with us first.
Ultimately it's your choice, but please.....anyone else that is considering this modification, do NOT discount it, please speak with anyone in the above list that has actually done it, so you can get experience based answers, rather than this load of .......'opinions'

good luck with whatever you do.

 

[Southernboy]

Your "opinion" is noted. Pity you also appear to have an issue with your opinions not being taken as gospel gookah.
The larger DISA does not equate to anything on it's own. It deals with a larger intake throttle body and consequently air flow as exists on the 3.0. You have the opinion that this same effect is automatically equivalent with a smaller throttle body, and as an opinion it's just that - unproven.
As you say, and I agreed, the benefit of the M54 IM comes in over 3500 rpm, so does my OEM set up - that's the way the DISA operates, but you car has lost some performance at low rpm due to the shorter runners and no DISA action to assist at those speeds - that's your compromise in performance. For you to enjoy any benefit at all from your mod, you need to be revving over 3500 - 4000 rpm.

I wouldn't know why you know your 1/4 mile time, but it would seem you've arrived at that info from having professional timing done at a venue other than the road down to the pub. Further, why include a list of other members in your comment about them not being "race drivers" when it wasn't suggested in this post by anyone other than yourself.
Lastly, your head banging frustration doesn't impress, and perhaps you should consider practicing humility or attend anger management therapy it may contribute to your general demeanour. At least my "opinion" has some basis in reality as demonstrated by the verifiable information I have provided and on which I have made my decision. The fact that I have made that decision is not an invitation for uninvited criticisism because you are in disagreement. Doing the mod to achieve some gains under certain conditions isn't a justification for doing it regardless. And it appears my aims are not in tune with your "opinions".

Read this again and understand -

What engine speeds, you say? That depends on the frequency of the pressure wave. If you stayed awake in high school physics, you may dimly recall that the frequency of a wave is inversely proportional to its wavelength (that is, a short wavelength means a high frequency and vice versa). In this case, the wavelength is determined by the length of the space in which the pressure wave can move, i.e., the length of the intake runner. All else being equal, the longer the runner, the lower the engine speed at which resonance supercharging occurs and vice versa.

 

[gookah]

Your "opinion" is noted. Pity you also appear to have an issue with your opinions not being taken as gospel gookah.
The larger DISA does not equate to anything on it's own. It deals with a larger intake throttle body and consequently air flow as exists on the 3.0. You have the opinion that this same effect is automatically equivalent with a smaller throttle body, and as an opinion it's just that - unproven.
As you say, and I agreed, the benefit of the M54 IM comes in over 3500 rpm, so does my OEM set up - that's the way the DISA operates, but you car has lost some performance at low rpm due to the shorter runners and no DISA action to assist at those speeds - that's your compromise in performance. For you to enjoy any benefit at all from your mod, you need to be revving over 3500 - 4000 rpm.

I wouldn't know why you know your 1/4 mile time, but it would seem you've arrived at that info from having professional timing done at a venue other than the road down to the pub. Further, why include a list of other members in your comment about them not being "race drivers" when it wasn't suggested in this post by anyone other than yourself.
Lastly, your head banging frustration doesn't impress, and perhaps you should consider practicing humility or attend anger management therapy it may contribute to your general demeanour. At least my "opinion" has some basis in reality as demonstrated by the verifiable information I have provided and on which I have made my decision. The fact that I have made that decision is not an invitation for uninvited criticisism because you are in disagreement. Doing the mod to achieve some gains under certain conditions isn't a justification for doing it regardless. And it appears my aims are not in tune with your "opinions".

Read this again and understand -

What engine speeds, you say? That depends on the frequency of the pressure wave. If you stayed awake in high school physics, you may dimly recall that the frequency of a wave is inversely proportional to its wavelength (that is, a short wavelength means a high frequency and vice versa). In this case, the wavelength is determined by the length of the space in which the pressure wave can move, i.e., the length of the intake runner. All else being equal, the longer the runner, the lower the engine speed at which resonance supercharging occurs and vice versa.

Mine are not opinions, its actual experience, that is the difference...

I have done it
You have not.

I know it works,
you say it wont...

Quarter mile time is from an annual BMW Show in the UK where you get chance to take the cars down the strip, so yes professional timings.

You are assuming to benefit from this is to be a racing driver. hence me quoting others that have done this mod but not for that reason.

everyone that reads this thread is able to make their own minds up Im sure.

You do not know how my car performs after this modification so don't presume your theories do,

We agree to disagree.

Merry Christmas.

 

[g8jka]

If by simply machining the OEM manifold I gain 15hp instead of 18hp as has been suggested by G8JKA, then I would prefer to retain the OEM manifold.

I never said anything about machining the OEM manifold. I changed my manifold for the M54 one. There are a lot of comments and opinions on this mod flying around the internet by people who haven't done it, some say it won't improve it, some say it will add 30hp. I have seen very little from people that back it up with actual figures. I have had mine on a dyno, as has Ant and Rha's on his old zed who have done the mod and each one has seen quite a large increase in HP and are backed up with actual dyno figures. Unless our cars were over 200hp to begin (doubtful) we have proven this mod works.

As I said earlier, the only way to prove this will work is to have the car on the dyno now, whilst it is stock and after once you have done the mod. This will give actual figures on the gains. As you are talking of machining the original manifold maybe you could get before and after figures from this to show the difference. Then you can come back with figures for others to see and we can prove which one is the most beneficial.

When your old manifold is off being machined, why not fit the M54 one and take the car for a spin to see the difference it will make?

 

[g8jka]

other than the road down to the pub

Manifold conversion or not, I bet I can shave at least a couple of seconds off my time on the way to the pub, compared to the time on the way back from the pub.

 

[Southernboy]

I have booked a dyno run for tomorrow - Tuesday- to get the "stock" out put figures.
On Wednesday, I'm doing the new intake cam install and then I'll run the car for a couple of hundred kms's for the DME to adapt.
Once that's taken care of, I'll do another dyno run to assess the improvements - if any with the new cam.
Thereafter, I'll do the IM swap to 1st the Re-worked M52 IM, an thereafter the M54 IM. Both with dyno runs. Once those numbers are in, I'll have a final re-map with one or other of the IM's as the final install and get the dyno numbers after the re-map.
I don't expect I'll have the final set up until sometime in January though. Once all is done I can post all the results for examination.

 

[g8jka]

This is the only way to prove the figures and find out exactly what works and what gives what power increases. Look forward to the results, keep us updated.

 

[t-tony]

It would be more use to most people doing the manifold first, as few do the cam change.

Tony.

 

[Rha]

Just caught up with this thread and hope your aware that the 2.8tu engine was restricted by BMW by altering the the IM thus restricting this engine to under 200bhp,they did something similar to the Z3M for the US market to keep it to the permitted 250bhp insurance,performance,emissions influences there, so I believe this fact alone tells you that some changes to the IM on the tu engine would make some gains and matching an already produced B30 IM that gets the very slightly bigger cc of the BMW B30 along with its cams up in the 220s was the way to go. The problem seemed to be that everyone thought the tu wasn't able to make use of better B30 IM so only a few tried and info was rare. I read up as much as pos before attempting this swap on my old 2.8tu but was amazed at how little info there actually was. Don’t be put off by what doesn’t seem an exact science, if you really don’t want upper Rev gains just go to a good engine mapper and you’ll have no work to do and you’ll have guaranteed 12bhp and low down in the Rev range for £250-£300 all done without lifting a spanner. It's now a well known fact in our circles that this engine works best with the slightly bigger and shorter inlet ports of the M54B30 which I suspect BMW wanted to fit( because it fits and was already available) but pushed it over the 200bhp limit hence the smaller DISA and longer ports to slow things down, if you read up on what the DISA actually does and look at how it works you’ll hopefully see why. If you go for the M54 IM you’ll have the best of both worlds, you can get the mapping done to give very slightly more gains in lower Rev range. Your inlet cam change will no doubt bring some benefit and with the better B30 IM who knows, theory tells us should get you more power but just how much cost is involved tells the bigger picture.
Someone has to be the ginea pig and spend and try these mods or no one gets the benefit. I was prepared as was others on here and had to do it alone with very little info, so if your willing to take the risk now with plenty of info already available just go do it, too much talk is not getting anything done, the industry isn't interested in this mod as the numbers wanting it just won't bring in the profits. The few people who know anything about this mod are mostly on here so why not go add yourself to the list, if it doesn't get you what you want then maybe you've gone and bought yourself the wrong Z. BMW are well known to strangle some of their engines so not to compete with stable mate alternatives just makes after market tuning more difficult.

Looking in/on with interest.
RHA,Roy.

 

[Southernboy]

So.... 2019.
In the interim, I first did the intake cam swap which was a lot easier than I anticipated. The fact that I had the use of the Cam / timing fitting tools from a buddy, made the job straight forward. Also, he printed out the BMW guide to doing the task of removal refitting, which if followed step by step makes it do-able by a novice with tools.
Next, I did the intake swap. Having looked at the OEM intake and how grungy it was, I decided to simply fit the MB30 and skip the PT machining the OEM manifold - the cleaning thing made me spontaneously lose speed...
Anyhow, the results of the upgrades has been the ease with which I can out perform in acceleration and top end, a 4 door 3.0 BMW saloon.
Granted, he has some extra weight on board.... but nonetheless, the Z3 is heaps quicker,
I haven't yet done a remap - financial issues - but will do so asap I can afford to.

 

[Lee]

Hallelujah we got there in the end. Now reep the rewards, the ECU will slowly adjust to the extra airflow and you'll start noticing the extra performance.