N55 swaps/interchangability

CalvinNismo

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Any chance you have a new style vacuum pump laying around? Would it be possible to just swap the back half of the vacuum pump instead of the entire thing? Would save a bunch of work for me with what I am trying to do... Looks like the front half of the vacuum pump is the same and it's the back half that mates to the HPFP that is different (hpfp mount is different and new style doesn't have the vacuum port since it's EWG).
Did you find out the answer to this? Seems like the main stumbling point for swapping from an N54 style HPFP N55 PWG, to any other N55. Would be nice to just have to swap the back half of the vacuum pump and not have to mess with the timing chain sprocket.
 
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jooobie

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Nov 16, 2022
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Did you find out the answer to this? Seems like the main stumbling point for swapping from an N54 style HPFP N55 PWG, to any other N55. Would be nice to just have to swap the back half of the vacuum pump and not have to mess with the timing chain sprocket.

I finished my swap a few months back and no you can't use the pump that's attached for the newer hpfp to retrofit it on the n54 hpfp.
Unfortunately you need to take it the engine chain and re-bolt it with the older style vacuum pump to make it work. Its not difficulty to do but it does requires the proper tools to hold the sprocket in place so that you may torque it to the correct value.
 
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CalvinNismo

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Thank you!

Its not difficulty to do but it does requires the proper tools to hold the sprocket in place so that you may torque it to the correct value.
Did you get hold of genuine BMW tools? Or did you buy some? Any brands/part numbers so I can get a rough price for the tools?
 

Fru5tum

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Bringing this back as it’s the only lead I have on it.
Any chance you have a new style vacuum pump laying around? Would it be possible to just swap the back half of the vacuum pump instead of the entire thing? Would save a bunch of work for me with what I am trying to do... Looks like the front half of the vacuum pump is the same and it's the back half that mates to the HPFP that is different (hpfp mount is different and new style doesn't have the vacuum port since it's EWG).
I have a 2016 435i N55 EWG and I’m trying to use a 2011 335i N55 PWG Block in it.

Were you able to make any adjustments to the vacuum pump setup to accommodate for the chain tensioner?

On a whim, I used an F-Chassis Oil Pump on my older n55, however, I had to dremmel out the hole on the chain bracket for the oil pump sprocket so the bracket would sit flush. E-chassis style bracket with leaf spring tensioner with F-Chassis style hpfp and vacuum pump combo. (I am not entirely sure if it’s necessary to use the f style oil pump, but we lost a block and blamed it on the e pump. It’s no trouble to cut ears out on the bracket to make it flush)

For a while I didn’t have issues with this, but it seems there’s a problem area that blows the bracket constantly. Either the tensioner will go, or now even, the bracket appears to have also split in half after the tensioner gave out.

At the end of the line with this, might just be better to get an f-chassis block just to use newer hydraulic tensioner.

How far did you get along with this any of this? I like the idea of swapping the front of the vacuum pump to the E-chassis half, to match the e chassis tensioner. Seems like that might even be the only possible option left. Did you do this? Did it work for you?
 
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Bnks334

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Bringing this back as it’s the only lead I have on it.

How far did you get along with this any of this? I like the idea of swapping the front of the vacuum pump to the E-chassis half, to match the e chassis tensioner. Seems like that might even be the only possible option left. Did you do this? Did it work for you?
Yes, this is what people do. Use the e-series vacuum pump. I don't recall if you can just swap the back-half of the vacuum pump. It does come apart but I never had both on hand to see if they mate together.
 

Fru5tum

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Yes, this is what people do. Use the e-series vacuum pump. I don't recall if you can just swap the back-half of the vacuum pump. It does come apart but I never had both on hand to see if they mate together.
Still tuned in, going to see if I can share some pictures soon, as I have both on hand and want to figure this out.

For the 4 series, it was easier to source a F Block and not have to bother with it at all. I highly recommend going that with that option, so much less headache, and the car loves it :)

The problem prevails; as I have it now we still have an N55 PWG E chassis block going into a F30. I have no issues mounting the entire E Chassis (n54 style) vacuum pump and HPFP. Bolts up no issue, but I have to swap the hard lines out. The plug for the HPFP is different, they are similar but keyed enough to where they will not connect. If someone has done this before, have you done this and just spliced in a N54 style connector?


We’ll still be trying both ways,

1. Take the back half of the F pump and attach to front half of E pump.

2. Leave E pump as a whole, and splice in connector.

I am familiar with coding but hoping I don’t have to cross that bridge. Will update soon.
 
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Fru5tum

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Got a little bit of an update, I know a lot of people were saying the housings couldn’t be split and matched, and that is indeed the case. I got some pics of this and why.

E chassis vacuum pump/HPFP has a big fan pin (for lack of better words) that separates and fits between the vacuum pump cover, and the HPFP. This is the vacuum pump internals.

F chassis vacuum pump/HPFP has a big fan pin that does not separate from the HPFP. From what I can tell, it is part of it. If it does come apart, the two ends are significantly different, with the E chassis having a big dowel cut in the middle to the drive, and the F chassis not.

In theory, you can take the F HPFP and Fan Pin and put it into the E chassis vacuum pump housing, but congrats, you just created an F chassis Vacuum Pump/HPFP, with the same F chassis internals and drive as you started with, and will run into the same compatibility issues with the tensioner.

Pictures should be in my next post. F HPFP on the left. I know it was mentioned before, here is the visual reason.

Next step is N54 harness snip for the connector, and some fuel pressure measurements.
 
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Fru5tum

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IMG_1252.jpeg

IMG_1255.jpeg
 
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Dynamics99

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So, I'm in the middle of swapping the oil pump system from the S55 into my 2011 N55 which carries an older style oil pump (shared with n54). The chain guide rail for the oil pump does not line up and needs to be shaved to enlarge a bit and cut to fit the protrusions. I already have the S55 oil pump system kit so I don't want to give up and go back to using the old design when the pump flows 18% more oil and has a pickup and baffle system to prevent starvation. Is there a way to frankenstein the newer design while maintaining the leaf spring tensioner? It's a PWG motor and I know they switched the design somewhere in 2012-2013 looking at realeom to a hydraulic tensioner. The new design has "cat ears" to clear the protrusions on the oil pump. A forum member on e90post had to cut the chain guide rail to fit the new pump protrusions but never posted pics. Any help or guidance would be appreciated since I'm rebuilding the motor for autox and track.
 
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houtan

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So, I'm in the middle of swapping the oil pump system from the S55 into my 2011 N55 which carries an older style oil pump (shared with n54). The chain guide rail for the oil pump does not line up and needs to be shaved to enlarge a bit and cut to fit the protrusions. I already have the S55 oil pump system kit so I don't want to give up and go back to using the old design when the pump flows 18% more oil and has a pickup and baffle system to prevent starvation. Is there a way to frankenstein the newer design while maintaining the leaf spring tensioner? It's a PWG motor and I know they switched the design somewhere in 2012-2013 looking at realeom to a hydraulic tensioner. The new design has "cat ears" to clear the protrusions on the oil pump. A forum member on e90post had to cut the chain guide rail to fit the new pump protrusions but never posted pics. Any help or guidance would be appreciated since I'm rebuilding the motor for autox and track.
Have you reached out to this person? This is the only person I know that’s actually installed one and made the modifications.

 
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Dynamics99

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Have you reached out to this person? This is the only person I know that’s actually installed one and made the modifications.



Looks like this is what he said in the post:
"The hole in the chain guide and tensioner bracket that the snout of the oil pump goes through needs to be enlarged as the snout on the s55 oil pump is larger."


So I have a cheap eBay chain guide rail for testing purposes. Gonna either make the hole larger or cut out the cat ears and see. I'll try to upload pics.
 
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Fru5tum

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Looks like this is what he said in the post:
"The hole in the chain guide and tensioner bracket that the snout of the oil pump goes through needs to be enlarged as the snout on the s55 oil pump is larger."


So I have a cheap eBay chain guide rail for testing purposes. Gonna either make the hole larger or cut out the cat ears and see. I'll try to upload pics.
I did what you’re suggesting myself when we were experimenting with our HPFP, we also tried using a newer style oil pump with the dog ears, and grinded out the chain bracket with a dremmel to fit the dog ears on the newer oil pumps, and it created a weak section on the bracket. (I traced the dog ears from a newer bracket, and matched them up delicately) This section snapped right at the ear on the right side, but I’m not 100% sure if it was because of the decreased durability in that section, or because of the leaf spring tensioner driving newer HPFP issue, or both. (i.e the tensioner broke, bounced around and broke the weak section)

We then tried welding the leaf spring tensioner to the newer style bracket that already had dog ears. We welded the leaf spring tensioner on, using a rivet in the original location, very small weld, but it seemed fine. This did not work either. We suspect the bracket got hot and the weld popped out. It held for about a week, and was the only fail point on that set up. (Big fail)

What you’re talking about is similar to the first thing we tried with our setup once we found the compatibility issue. We are about 99% convinced that that leaf spring style tensioner chain guide will not be reliable on anything other than the PWG N55, with the flat style oil pump, and N54 style HPFP. Anything else isn’t worth the lack of reliability and risk to us. We got extremely lucky to even save that block, considering we broke 3 brackets, the second time it threw metal shavings everywhere, and the last time it spun the crank hub oil gear.

We ended up getting a whole F Chassis EWG block that came with the hydraulic tensioner mounting holes, and newer bracket with dog ears.
This car has about 5k miles on it as we speak, on full E, FX-180, JB4 with MHD BEF. Our stress was eased, and if we wanted to test a S55 oil pump setup, or another oil pump, we wouldn’t have any concerns on the drive system for it. It is solid.

We still have that PWG E block to experiment on. Unfortunately, we had some things come up, so we haven’t done any testing on the set up that I mentioned in my earlier post. We had the valvetronic worm gear give out, and haven’t recovered quite yet. To clarify on that, we ended up using an N54 HPFP with the E chassis PWG leaf spring bracket and older flat style oil pump without the dog ears. This hasn’t been tested yet, but we’re confident it shouldn’t be an issue, as it’s identical to the OEM PWG E Chassis set up. (Our only concern is the efficiency of the N54 HPFP with the F Chassis DME)

Ultimately to my last point, our last option and one we debated on before doing what we did, was using the EWG, F Chassis Hydrotensioner Bracket, with the F Chassis Oil Pump (ears), and whatever HPFP setup we choose, by welding the hydraulic tensioner to the bracket, instead of mounting it to the block, or creating any weak sections in the aluminum bracket. We were skeptical of this, since our peasized weld before didn’t work for the leaf spring tensioner, however,

The Hydraulic Tensioner fits on a foot, on the F Chassis EWG bracket, and has a significantly larger surface area. We looked at so many options, and planned on welding the hydraulic tensioner, to the bracket on this foot. This was the next, most viable, and probably last option.

I know that you’re on a different adventure. If you’re not changing the HPFP, then I think it’s doable with a quality bracket. Just a thought. Plz share updates, as these things are a huge bottleneck for people doing N55 swaps in different year ranges.
Good Luck!!
 

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Dynamics99

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Post in thread 'S55 oil pan on N55 (e82)'
https://www.spoolstreet.com/threads/s55-oil-pan-on-n55-e82.9060/post-133959


Here is the link to HollRacing’s post. He has done over 3700 miles without any issues with the tensioner modification.

If you go through the post you can see what I did. I shaved bit by bit. I didnt trace out anything to make sure that i could retain the most material without taking away too much for stability. Once the veins on the pump fit the dog ears and the two asa bolt holes lined up, i stopped dremeling. I’m also using an aftermarket tensioner bracket (ik i should go with OEM but im balling on a budget lol) with new OEM grip disc sprocket for crankhub, oil pump sprocket, and vaccum pump sprocket. My original tensioner plastics were cracking so I decided to toss the old bracket out.

Ill be using the stock HPFP that came with the motor (build date 9/2010). So hopefully my motor does not get cooked. But once I get home I’ll take some additional pictures since I have torqued everything down on the bottom crankcase side except for the oil pan. I also did a spin test without the oil pump sprocket bolt in. It kept slipping off the oil pump snout initially because the dog ears were not clearing the veins on the pump. Once the dog ears were clearing the veins and the bolt holes lined up the sprocket was not backing off the snout. This was tested without the oil pump sprocket bolt again just to ensure minimal play vertically and horizontally. The only thing tightened down was the single torx bolt holding the tensioner bracket to the block and the vaccum pump bolt. So thats additional info.
 
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Fru5tum

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A new rabbit hole! Thats pretty sick. All of my knowledge pertains to the HPFP compatibility, so seeing another take on the oil pump is literally the other half to the puzzle.

One of the going theories for us and the leaf spring tensioner going out, is the amount of “drag” on the components it’s driving.

We were thinking that having the newer style HPFP with the different internals was creating a little extra drag; too much for that tensioner to handle.

The way variables work though; we were trying to use a F Chassis Oil Pump, with the ears, in combination with the F Chassis HPFP. I think the bigger problem was the resistance the newer HPFP had, but I wonder if the newer oil pump may have played a roll. Those two things at the same time may have been the real problem.

This is my first real look on the S55 oil pump for N55. I like how solid it looks, based on your pics on the other thread. It has the ears, like the newer EWG oil pump, and all the fancy stuff to keep it in check under load.

I saw you mentioned track, and you’re pretty deep into this area of the motor. What is your fueling setup in total? Is it just the N54 style hpfp? PI? Have you hit any limitations with that?

Since we still have the PWG block with the N54 Style HPFP, we were looking into developments. No definite plans for the block yet, so this is just lingering…


With all the take on the oil clearances, pressures and limitations, you’re definitely doing your part.
Thanks! Good Luck!
 

Dynamics99

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A new rabbit hole! Thats pretty sick. All of my knowledge pertains to the HPFP compatibility, so seeing another take on the oil pump is literally the other half to the puzzle.

One of the going theories for us and the leaf spring tensioner going out, is the amount of “drag” on the components it’s driving.

We were thinking that having the newer style HPFP with the different internals was creating a little extra drag; too much for that tensioner to handle.

The way variables work though; we were trying to use a F Chassis Oil Pump, with the ears, in combination with the F Chassis HPFP. I think the bigger problem was the resistance the newer HPFP had, but I wonder if the newer oil pump may have played a roll. Those two things at the same time may have been the real problem.

This is my first real look on the S55 oil pump for N55. I like how solid it looks, based on your pics on the other thread. It has the ears, like the newer EWG oil pump, and all the fancy stuff to keep it in check under load.

I saw you mentioned track, and you’re pretty deep into this area of the motor. What is your fueling setup in total? Is it just the N54 style hpfp? PI? Have you hit any limitations with that?

Since we still have the PWG block with the N54 Style HPFP, we were looking into developments. No definite plans for the block yet, so this is just lingering…


With all the take on the oil clearances, pressures and limitations, you’re definitely doing your part.
Thanks! Good Luck!
Motor is still being put together. Just finished the timing chain and camshaft adjuster sprockets two days ago. Been busy trying to fix my Panigale 959 starting issues (turned out to be a old battery lol). My motivation is like falling because its a lot of work even though I have ISTa but my friends are wanting me to track the coupe at NJMP this summer so I’m going to try to get more done this weekend.

The car is using the N54 style HPFP. Im nervous as hell to put it back together since its my first ever rebuild but the plan is that if the car runs and drives without tossing a bearing during break in then im planning to either go PS2 or Speedtech Pulsar 6266 with Port Injection and Motive Reflex. Before it blew up on my driveway it had MHD Stage 2+ with FBO(7.5 VSRF IC, VSRF Catless DP, VSRF ChargePipe). Its funny since I have two 335i’s. One is E92 and an e90. Both manual, alpine white, and M-Sport, and LCI with xenons but the e90 only has a chargepipe and stock tune with MHD installed. If the motor rebuild on the e92 goes well then I’m planning to retrofit another kit on the E90 so I can drive without worrying on tossing a bearing out.

I havent read on the HPFP differences between their variations but it could play a role if resistance was greater cause harsher chain lash. If you used the original tensioner off the motor then chances are the tensioner was already weakened under usage from heat cycles. If not then i wonder what would really cause it.
 

sw3rv1n9

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I actually have a question of my own, just new to the platform and not sure where to ask but came across this post. I’ve got a 2011 BMW 35i with the N55B30A and it threw a rod so I also need a new engine. I came across an N55B30A from a 2012 BMW 535i awd. What are the differences? Is the 535i motor compatible with my car if I switch over the ecu or is there more to it than meets the eye? Thank you!
 

Fru5tum

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I actually have a question of my own, just new to the platform and not sure where to ask but came across this post. I’ve got a 2011 BMW 35i with the N55B30A and it threw a rod so I also need a new engine. I came across an N55B30A from a 2012 BMW 535i awd. What are the differences? Is the 535i motor compatible with my car if I switch over the ecu or is there more to it than meets the eye? Thank you!
You lucked out, from what I know, those two motors should be practically identical. Main difference to look out for is PWG vs EWG, and N54 Style HPFP vs vertical newer style HPFP. The AWD oil pan won’t work, but it can be changed out for the RWD version. The downpipes might be different on the 5 series also. Of course the motor mounts are different, but I assume all you are concerned about is the short block.

If they are different, then you’ll need to do more research. Check the build month on those two cars and those parts. Spot it sooner than later and save yourself the trouble.

Also, sometimes they change really little stuff, subtlety. I think there was a thing going around for N54, where some had newer cam ledge seals and some didn’t, wherein that case, everything would have been identical, with minor minor changes to stuff like the type of seal. I don’t know about those things on N55, I’m pretty sure the vanos gears got a facelift at some point, no idea when.
 

sdo92

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This is interesting thread, just wanted to mention that Nexsys Motorsport made a HPFP and DI delete kit with wire adapters to run PI off the N55 ECU. It may be coming to N55 later hopefully. It may also be a cheaper route instead of HPFP and injector replacements. It could also remove the parasitic loss from the engine and clean valves. Could be harder to tune but Im waiting for this also.

Best of luck Dynamics99 on the s55 oil system upgrade, I want to do this too if it all goes well. Just thought I'd mention to please prime your oil on first start up cause thats how my engine got messed up. Cheers
 

Zoro123

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THIS IS SUCH A COMMON PROBLEM HOKY FUDGE!!!! It’s like every other day someone gets a spun bearing on these engines 😬