S54 Build Decisions: Turbo vs. High-Revving NA – Seeking Experienced Opinions

[digger]

One option if new rockers aren’t available is to reuse by getting them refinished by credible cam shop. They may be able to get them DLC coated to.

[Mike RT4]

There was probably nothing wrong with the Schrick cams, it was most likely the BMW followers. There was a period a few years ago where BMW changed supplier and the new ones were made of chocolate and destroyed cams. You will remember when this happened, as the followers were on back-order from Schrick for a very long time (as they just DLC the OEM ones) as once Schrick realised there was an issue with them, they rejected them and made BMW remanufacture them.

I was personally also on the receiving end of a bad batch of followers that took out a brand new set of (OEM CSL) cams within a few thousand miles. Luckily the warranty picked up the costs or I would have been hugely pissed. It was bad enough being without the car for another few weeks while it was repaired (again).

[bigjae46]

Known issue and documented now in new manufacturing process. Gone is the usual old school black nitrided coated lobes. All new cams now come polished, forcing your hand on buying the new dlc rockers (the correct way to install but was not always the case, members here with older engines around 200kms fitted 288/280 cams on oem followers with no issues). This happened to me in 2023 when I installed 280/272 cams.

If you get a newer set of cams, can't you have them nitrided yourself?

[CrisSilberGrau]

Do you have any photoes of damaged schricks? I've bought ones- silver ones, without coating and seems like same problem

Known issue and documented now in new manufacturing process. Gone is the usual old school black nitrided coated lobes. All new cams now come polished, forcing your hand on buying the new dlc rockers (the correct way to install but was not always the case, members here with older engines around 200kms fitted 288/280 cams on oem followers with no issues). This happened to me in 2023 when I installed 280/272 cams.

[BMWfanz]

Building an n/a s54 is very expensive and it will be totaly unrelieble, i have started with decat and no name carbon airbox, this set up ended with fully ruined engine , because only few tuners in the world know how to tune it, after this we build engine with 11.5 compression, +0.5 je pistons ,fcp rods, balanced cranck and schrick 280/288 cams with supertech springs. Then one other guy tried to tune it without any numbers 315hp to understand , after we tune it with evolve , wich is crap tune also , 330hp, finaly i have spent hours reserching and found one guy named Paul Cloud , pcs tuning ,finaly with Paul we made car safe and fast last dyno attached (superflow) 98 octane with vp fuel madditive. After few track days shricks turned into garbage, in some places like new in some got wear as it was half million km , when we made test in lab , expert made conclusion that it was incorectly hardened , shrick refused in warranty so from thos moment we dont use schrick in any builds.

Do you have any photoes of damaged schricks? I've bought ones- silver ones, without coating and seems like same problem

[9kracing]

Revving the S54 to 9500 RPM will significantly shorten the lifespan of the build, no way around it.

I was going to quote you and ask if you had a reason high RPMs would be unreliable, and then my hero posted below you and basically said what I was going to.

When you start talking about those kinds of RPMs you have to take into account a myriad of factors, such as piston speed, rod stretch, etc.

What you should really be doing is calculating the piston speed to see how high the mean / average already is on the S54. To keep this to a manageble level, you want a small stroke (hence why you see the term "de-stroked" (which reduces the engine capacity for a given bore size (and vice-versa).

At 8000 the S54 for has a high 24.267m/s average. Due to the relatively large stroke (91mm), increasing that to 9500, takes it to 28.817m/s average, which is WAY to high for any engine longevity - the strain on the rods will be huge.

As an example of a high revving engine (F20C), which goes to 9000, due to it's smaller stroke (84mm), so despite the higher rpm, it still only has an average piston speed of 25.2m/s.

A 458 has an even smaller stroke of 81mm, so it's same 9000rpm redline as the F20C has practcally the same piston speed (24,3) as the S54 does at 8000rpm.

The S65 is even lower, with a stroke of 75.2, so even with it'ts 8400rpm rev limit, it has a low 21.056m/s average.

So basically the S54 is already on the limit of it's design at 8000rpm (8300 would give it the same piston speed as the F20C). There is no way to gain any capacity due to the bore spacing. What would have been nice if BMW had continued the development of the S54 in the same way that Porsche did with their flat six. Imagine a 4.0 litre, 14.5:1 straight six with an 84mm stroke - that would be safe to 9000 and should make a comfortable 500bhp N/A.......

Not sure if would still fit in the E46 engine bay due to the requirement of 100mm bores giving at least a 78mm extra block length (100mm to give some meat on the wall thickness), but we can dream LOL.

[Mike RT4]

What you should really be doing is calculating the piston speed to see how high the mean / average already is on the S54. To keep this to a manageble level, you want a small stroke (hence why you see the term "de-stroked" (which reduces the engine capacity for a given bore size (and vice-versa).

At 8000 the S54 for has a high 24.267m/s average. Due to the relatively large stroke (91mm), increasing that to 9500, takes it to 28.817m/s average, which is WAY to high for any engine longevity - the strain on the rods will be huge.

As an example of a high revving engine (F20C), which goes to 9000, due to it's smaller stroke (84mm), so despite the higher rpm, it still only has an average piston speed of 25.2m/s.

A 458 has an even smaller stroke of 81mm, so it's same 9000rpm redline as the F20C has practcally the same piston speed (24,3) as the S54 does at 8000rpm.

The S65 is even lower, with a stroke of 75.2, so even with it'ts 8400rpm rev limit, it has a low 21.056m/s average.

So basically the S54 is already on the limit of it's design at 8000rpm (8300 would give it the same piston speed as the F20C). There is no way to gain any capacity due to the bore spacing. What would have been nice if BMW had continued the development of the S54 in the same way that Porsche did with their flat six. Imagine a 4.0 litre, 14.5:1 straight six with an 84mm stroke - that would be safe to 9000 and should make a comfortable 500bhp N/A.......

Not sure if would still fit in the E46 engine bay due to the requirement of 100mm bores giving at least a 78mm extra block length (100mm to give some meat on the wall thickness), but we can dream LOL.

[bigjae46]

The Steve Dinan/Carbahn stroker stroker s65s don't seem to be the most reliable, and they don't even start out undersquare like S54. I don't think a stroker, by anyone, is likely a long term reliable S54 solution.

I'm just talking about the engine blowing up soon after the rebuild. Revving the S54 to 9500 RPM will significantly shorten the lifespan of the build, no way around it.

Is the S54 a decent stroker candidate? I thought there wasn't much material between the cylinders to start off with. I know there are 3.4L and 3.5L kits floating around, haven't seen many stroker builds. The only one that comes to mind is Garo Haroutianin (spelling?) in the orange hill climb M3 with a VAC stroker S54.

[Obioban]

The HPF experiment was quite interesting years ago. IIRC, 33psi was the ceiling on stage 4? I don't see many of those cars still going. I'm positive I'd see them on facebook and instagram. But you can get to 420whp pretty easily on 7-8psi of boost? I don't think that will stress the motor very much. Your issue will be managing heat. I think you destroy the intake noise since you'll need a different intake manifold.

An NA build would be far more interesting. I think the comments above about - it will be expensive - all miss the mark very badly. Yes, the parts won't be cheap. But here is why I say that.

The biggest concern is build quality which translates to reliability. I've seen far more cases of engine builds gone wrong vs gone right. Probably a 9:1 ratio which is quite bad. Tip #1, using a racing shop is usually the wrong answer, using a machine shop is a terrible answer. They know a decent amount about a lot of stuff, not the expert on engines. A while back, I had an enlightening encounter with a shop that builds motors for dune buggies. Those motors spend hours at redline so those motors have to be precisely designed and built. So I'd do a ton of research outside of the forum to find an engine guy.

The one guy I would trust with a reliable stroker build would be Steve Dinan, not the Dinan parts shit show, the actual guy who has a long track record of building NA BMW S engines that won IMSA 4 years in a row with a 20 year old engine. And that guy's labor will cost more than the parts.

That is where most go wrong. They hire some ape who talks a good game and it becomes a roll of the dice. And picking the wrong engine builder is an expensive mistake.

Personally, I'd love to throw in a B48 with 420whp. Those engines should be cheap, easy to find, and fairly reliable even with more boost.

The Steve Dinan/Carbahn stroker stroker s65s don't seem to be the most reliable, and they don't even start out undersquare like S54. I don't think a stroker, by anyone, is likely a long term reliable S54 solution.

[bigjae46]

The HPF experiment was quite interesting years ago. IIRC, 33psi was the ceiling on stage 4? I don't see many of those cars still going. I'm positive I'd see them on facebook and instagram. But you can get to 420whp pretty easily on 7-8psi of boost? I don't think that will stress the motor very much. Your issue will be managing heat. I think you destroy the intake noise since you'll need a different intake manifold.

An NA build would be far more interesting. I think the comments above about - it will be expensive - all miss the mark very badly. Yes, the parts won't be cheap. But here is why I say that.

The biggest concern is build quality which translates to reliability. I've seen far more cases of engine builds gone wrong vs gone right. Probably a 9:1 ratio which is quite bad. Tip #1, using a racing shop is usually the wrong answer, using a machine shop is a terrible answer. They know a decent amount about a lot of stuff, not the expert on engines. A while back, I had an enlightening encounter with a shop that builds motors for dune buggies. Those motors spend hours at redline so those motors have to be precisely designed and built. So I'd do a ton of research outside of the forum to find an engine guy.

The one guy I would trust with a reliable stroker build would be Steve Dinan, not the Dinan parts shit show, the actual guy who has a long track record of building NA BMW S engines that won IMSA 4 years in a row with a 20 year old engine. And that guy's labor will cost more than the parts.

That is where most go wrong. They hire some ape who talks a good game and it becomes a roll of the dice. And picking the wrong engine builder is an expensive mistake.

Personally, I'd love to throw in a B48 with 420whp. Those engines should be cheap, easy to find, and fairly reliable even with more boost.

[MAXixt]

Car specs : karbonius race air box, stock ecu ,pcs tune, csl map, je pistons +0,5, 11.5 compression,balanced cranck, fcp rods, driftworks flywheel,sachs race clutch, supersprint raceheaders, custom middle section, arqray titanium rear box (9kg) stock fuel sistem

[MAXixt]

Building an n/a s54 is very expensive and it will be totaly unrelieble, i have started with decat and no name carbon airbox, this set up ended with fully ruined engine , because only few tuners in the world know how to tune it, after this we build engine with 11.5 compression, +0.5 je pistons ,fcp rods, balanced cranck and schrick 280/288 cams with supertech springs. Then one other guy tried to tune it without any numbers 315hp to understand , after we tune it with evolve , wich is crap tune also , 330hp, finaly i have spent hours reserching and found one guy named Paul Cloud , pcs tuning ,finaly with Paul we made car safe and fast last dyno attached (superflow) 98 octane with vp fuel madditive. After few track days shricks turned into garbage, in some places like new in some got wear as it was half million km , when we made test in lab , expert made conclusion that it was incorectly hardened , shrick refused in warranty so from thos moment we dont use schrick in any builds.

[Sharocks]

I have a fairly modified NA car and a decently modified SC car.

I don't have direct experience with a turbo S54 but I have friends with them.

My advice:

Aside from headers, intake, lightweight wheels (under 18 lbs a corner, no Apex bullshit), better brakes, decent coilovers, better seats, and a short shifter, I'd leave it alone.

If you're chasing some special engine, it's already a special engine. It's on the spectrum.

[nextelbuddy]

lots of talking going on here, im not going to dive into the penis measuring contest of who knows the most about this or that.

all i can speak to is my experience with My S54 turbo setup.

i have a street setup making 530 whp at 11 psi on a bottom mount SPA cast manifold and Borg warner S366SXE turbo with a 1.0 AR on the exhaust side. i have a custom scavenge pump setup for my Oil drain as the turbo was a bit larger and hung low preventing a good gravity drain.

i have no engine work done, completely stock and was turbo charged when i had about 135k miles. i've put about 10k miles on the turbo setup now with no major issues.

i run no cats and just a 3 inch down pipe mated to a dual Y pipe into stock section 1 resonated and status gruppe non resonated section 2 and status gruppe SCZA section 3. my car is not loud and sounds like a stock turbo car and i love that part, no more screaming engine exhaust sound when pulling away in traffic which i hated, nothing like a loud ass car making so much noise and not going anywhere

the car is on a stock MSS54HP DME with a custom HTE turbo tune running E85 100% and the car drives and feels like a stock car just much much faster which was my goal ultimately.

could i track my car? perhaps but I dont run an aftermarket oil cooler, just a stock one and i have a stock cooling system (all updated from FCP but stock parts)

my oil temps on the street barely ever reach the middle mark compared to my S54 wagon which does exceed that mark on hot days but i am taking a guess that my turbo car runs e85 so engine runs a bit cooler, my custom oil drain setup also incorporates a small aluminum sump tank hanging off the turbo which probably also helps cool my oil along with the additional lines.



i also have an S54 SMG wagon with CSL airbox, euro headers, cat delete and stock section 2/3 and its just louder and its ok. definitely not as fun as the turbo car but for a daily driver its all i could ask for and exactly what i wanted.

let me know if you have any questions about my turbo setup specifically. or want to see or hear videos.


If you go turbo and stay stock compression, you need to run e85 to run more than 10 psi of boost. pump gas detonates and you need to run meth injection OR e85. running stock compression ration definitely makes good peppy power. you can run 9:1 but have to run more boost and need more tuning and you lose some of that low end spool and tq

my turbo car has unopened S54 stock everything with about 145k miles on it
my wagon has a rebuilt S54 with new rod bearings, HG and all new valve stem seals and every other gasket and seal replaced.

[oceansize]

One guy I know for sure on the board who is currently running turbo is nextelbuddy