Technical Hydra Performance 135 Leichtbau State of the Art Thread

[Rob@RBTurbo]

Great thread.

The head discussion reminds me of my first observations of the N54 head as well, posted about it many many many years ago but it never went over well with the masses. The gist was that when you compare all aspects to any other respectable head on any other turbo platform, the N54 head is laughable although it does still seem to get the job done (for most). But what is great is that you found something that appears to be much better and a direct drop on, that is awesome and can't wait to here/see more on that as time progresses.

The turbo solution looks solid. Not going to say I'd agree with everything you've done and/or are saying, but can certainly say the custom tubular manifolds look very nice and what you've said about other aftermarket cast turbine housings is also spot on. We'd always been open to better housings for performance, and could've bought the ones everyone seems to think were gold for over a year now yet haven't. Why not? Because we agree with much of what you said already plus some, they just need much more help in several ways. Would be interested to see what you have going on with this one to see if all the things we disliked you've addressed, much like the nice touch with keeping that divider intact.

All said keep up the good work.

Rob

 

[Ace718]

No, just a VTT bolt capture kit, and hub fix. Trouble is the hub fix was only made available literally 4 days after I spun my hub the first time I hit the limiter @ 8k.

My reasons for not building the motor are twofold, first of all I don't have the traction available to be able to run high boost to really make a built motor worthwhile, despite having all the "right" chassis mods. I changed out the bearings, opened up the rod and main clearances a little, and replaced all the TTY bolts, but otherwise left everything factory. I thought long and hard about adding Carrillo rods, on account them being ~50g lighter each, to make life easier on the rod bearings, but in the end decided not to sink any more money into the N54 bottom end, in the hope that sometime in the near future I may be able to swap an S55 shortblock instead, custom DME work permitting

This build is really unique and I'm excited to see how things progress. My only question is why not go ahead and build the bottom end for the sake of longevity, if nothing else, after investing so much time and effort? Of course this question hinges ultimately upon what your power level ends up being set at.

I'm very interested to see how much efficiency you will gain with regards to psi:hp.

 

[fmorelli]

One tough thing about this thread, is it lifts up a bunch of different worthwhile topics. I just wanted to share, for those of us in the USA, why we never saw the N53.

USA and Australia still continues to use the N52 for the same reason that we use the N52 – high sulphur content in our gasoline. Yes, the sulphur issue is not just with our diesel. ... According to BMW, they are able to introduce the N54 and N55 with direct injection here because the forced induction changes the combustion flame in a way that allows the injectors to be okay with the sulphur content here, but that’s as technical an explanation as I could get so far.

Just so I keep it to one post, @Rob@RBTurbo appreciate your comments on the turbo post. Just curious where you have possibly different perspective, given all the experience you have in this realm. If you are willing to share, it would be interesting to hear. (from your comment, Not going to say I'd agree with everything you've done and/or are saying).

 

[Dreyo27]

If you don't mind me asking, why not use an N52 head without DI?

This way you get rid of the unreliable HPFP and DI injectors. Most importantly it would allow you to use a cheap off the shelf Standalone.

 

[Rob@RBTurbo]

Just so I keep it to one post, @Rob@RBTurbo appreciate your comments on the turbo post. Just curious where you have possibly different perspective, given all the experience you have in this realm. If you are willing to share, it would be interesting to hear. (from your comment, Not going to say I'd agree with everything you've done and/or are saying).

Filippo,

I've become quite known for "raining on parades", but typically it is for damn good reasons. In this scenario I really respect an overwhelming majority of what was said, much of the theory is perfectly inline with reality and OP clearly has a good understanding of some of the challenges and fundamentals with turbocharging this platform. While it would be nice to actually visually inspect some of the components in person to have further insight, I'd have to take this one at face value based on what has been stated. The information as presented while knowing what I know really seems that could be valid, truthful, and sincere. All said would rather just leave it as it was stated in that comment than focus on some of the more petty things.

Rob

 

[Hydra Performance]

If you don't mind me asking, why not use an N52 head without DI?

This way you get rid of the unreliable HPFP and DI injectors. Most importantly it would allow you to use a cheap off the shelf Standalone.

Don't underestimate the time and effort needed to properly dial in a standalone from scratch, not to mention the inevitable driveability trade-offs and loss of functionality. I'll stick with the stock DME thank you very much

 

[Rob09msport]

It seems like not only is passion for the platform a driving force but also this is r and d for a reliable build that can be reproduced and marketed piece by piece or whole. A standalone would throw a larger effort , expense, and alot of variables.

 

[fmorelli]

Filippo,

I've become quite known for "raining on parades", but typically it is for damn good reasons.

Rob, gotcha. I only asked as your original comment implied that there was more to say where you seem to have a different point of view, so it obviously begged the question.

Filippo

 

[Hydra Performance]

This build is really unique and I'm excited to see how things progress. My only question is why not go ahead and build the bottom end for the sake of longevity, if nothing else, after investing so much time and effort? Of course this question hinges ultimately upon what your power level ends up being set at.

I'm very interested to see how much efficiency you will gain with regards to psi:hp.

Like I said earlier, I am severely traction limited as-is, and won't be targeting high boost levels for anything more than a glory run on the dyno or a dragy pull for validation purposes. Besides, I would rather not invest too much in the N54 bottom end, as the plan is to eventually migrate to an S55 shortblock once certain advancements are made on the DME side.

As for whp/psi here is what I am conservatively expecting to see:

~580whp SAE @ 17.4psi on 99RON pump gas
~635whp SAE @ 21.4psi on 99RON pump gas
~750whp SAE @ 26.1psi on race gas

Just to put things into perspective, plugging the 21.4psi numbers into a variety of drag racing/performance calculators invariably leads to 138-139mph traps on a lightweight car like mine. Hopefully that should explain my rationale for not bothering with a built bottom end, especially when you consider I've still got only 45k on my shortblock with excellent compression across the board.

In any case I hope to validate as many of these claims as possible over the coming few weeks, just need to replace a few bent valves and a crank hub first lol

 

[Hydra Performance]

Took my car back apart today, couldn't help but notice how beautiful the discolored SS manifolds/hotsides looked, so I thought I'd share... More pics to come later.

 

[langsbr]

I know your manifolds are custom made, but what of the rest of the turbos? Are they stock turbine housings with custom CHRA and compressor housings, or all stock, or totally custom?

 

[Hydra Performance]

I know your manifolds are custom made, but what of the rest of the turbos? Are they stock turbine housings with custom CHRA and compressor housings, or all stock, or totally custom?

Turbos are of my own development, and will be coming to market in mid-November. I will make a suitable announcement thread shortly, but in the meantime you can read up more about them in the post below:

https://bmw.spoolstreet.com/threads/hydras-135-leichtbau-state-of-the-art-thread.4232/#post-58653

 

[langsbr]

Turbos are of my own development, and will be coming to market in mid-November. I will make a suitable announcement thread shortly, but in the meantime you can read up more about them in the post below:

https://bmw.spoolstreet.com/threads/hydras-135-leichtbau-state-of-the-art-thread.4232/#post-58653

You must've added that after the fact. I swear I read every post in this thread, lol. I am curious if the N53 cylinder head will require the Schrick camshafts to work. Also, I had read that aftermarket pistons are required to use the schrick cams, so how are you circumventing that, or was that misinformation?

I would think there would be some excellent benefits from just the cylinder head with stock cams, if possible.

 

[Hydra Performance]

You must've added that after the fact. I swear I read every post in this thread, lol. I am curious if the N53 cylinder head will require the Schrick camshafts to work. Also, I had read that aftermarket pistons are required to use the schrick cams, so how are you circumventing that, or was that misinformation?

I would think there would be some excellent benefits from just the cylinder head with stock cams, if possible.

No worries, I added the info about my turbos ~48hrs after initially creating the thread. Typed it all up but then my browser crashed, so I had to do it all over again since drafts aren't automatically saved when you're editing a post, but oh well... Needless to say, I haven't written this much since college

The N53 head, as I will be offering it, is a PnP setup on our engines. Sure you can reuse your stock cams, but IMHO if you're going through all this trouble why would you want to? I would guesstimate the benefit from the N53 head + cams together to be on the order of 70-100bhp on a non-choked setup. The head alone isn't going to net you anywhere near that much.

As for the Schrick cams, keep in mind that they offer two "flavors" , low-lift (what I am running), and high-lift. The former are intended for use with the stock valve-springs, while the latter are made for use with aftermarket valve springs. I don't recall ever hearing about the latter not being suitable for use with stock-pistons, and I find that claim to be dubious when I apply intuition and common sense. The difference between the two is ~1.0mm @ maximum lift while maintaining the same duration, so I doubt the valve lift @ overlap (when the valve is closest to the piston, specifically the exhaust) is more than a couple tenths of a mm larger on the high-lifts, not enough to be an issue...

 

[langsbr]

I didn't realize there were two lift profiles, but VAC is who says aftermarket pistons are needed.

With the low lift cams, won't it simply push the powerband further to the right with added duration? I know a lot of people love high rpms, but I always thought RPM stands for ruins people's motors.

 

[Hydra Performance]

I didn't realize there were two lift profiles, but VAC is who says aftermarket pistons are needed.

View attachment 17041

With the low lift cams, won't it simply push the powerband further to the right with added duration? I know a lot of people love high rpms, but I always thought RPM stands for ruins people's motors.

Stock lift is 9.7/9.7mm, The low-lifts have a lift of 11.5/10.5mm , whereas the high-lifts run 12.5/11.5mm. Both have a nominal duration of 268-degrees, with no @1mm or @0.050" duration available to distinguish the two. The high-lift cams should theoretically offer a fatter torque curve than the low-lifts; however a Lift/Diameter ratio of >0.39 is complete overkill on all but the most highly-developed of cylinder heads, so I don't think the difference in performance between the two would be all that profound, especially when you consider the additional stresses on the valvetrain, timing chain, crank snout, etc. from the additional lift (and spring rate needed to control the more aggressive lobes)

I'm normally of the RPM = Ruins People's Motors school of thought, however our cars have enough problems running high boost as is, from fueling and bottom-end limitations, to misfires, tranny limitations, traction limitations, etc. It just never seems to end. With that said, a 7500-8000 rev limit isn't a huge deal on a modern 500cc/cyl DOHC engine...

 

[langsbr]

Will you offer the turbo manifolds in just an n53 flange for your cylinder head, or will there be an existing n54 version? You said the cylinder head is going to be pnp, does that assume you will be using your turbos, or do you have a method to mount n54 flange manifolds to it?

 

[Traf]

I think the turbos will exist with both N53 and N54 manifolds

 

[kayzrx82]

Do you know if the n53 head is as braced in the casting on the dome of the cylinder vs the n54 head ? Just curious if the casting are the same between the 2 heads in that area .

 

[Hydra Performance]

@langsbr, I can supply the head with flanges for those who want to build their own manifolds, or I could supply the head with custom manifolds to suit my twins. I might be able to modify MMP manifolds to make them fit, but I can't be certain without examining them in person...

@kayzrx82 , I can't be absolutely sure without chopping both heads up and measuring, but they do appear to be based on the same casting/overall design...