s52 vs. s54 blocks?

[Hobbs64]

Anyone know if the s52 and the s54 blocks are interchangable? I am thinking of using my modified long block in conjuction with the s54 head cams induction and electrinics...etc. Ruker are you out there?

I bet one of you knows this off the top! Thanks:

[rukman]

no...the s54 block has more in common with the old euro motor than it does with the U.S. Spec block...i doubt you could get the head from the s54 bolted onto the U.S. spec block...

[///MTV]

s52 block is aluminium
s54 block is iron

[SilverStreak]

No, the S52 is iron also.

But I do think there is a slight displacement difference too. And I do mean, "slight", but enough of one to make parts not interchangable.

This is just an example, I don't know the real numbers involved. But eventhough both are listed a 3.2 liters I think it's something like this:

S52 = 3196 cc
S54 = 3248 cc

Again, not sure of the exact #'s but I did read somewhere that there is a slight displacement difference between the 2 motors...

[rukman]

s52 is iron
s54 is iron
s52 = 3152cc, 86.4mm x 89.6mm (bore x stroke)
s54 = 3246cc, 87.0mm x 91.0mm (bore x stroke)

the differences don't end there....its a completely different engine really...

[SilverStreak]

The S54 is aluminum? Really? I had no idea...

[SilverStreak]

But at least I called the displacement difference thing...

[M powered]

I read somewhere that the S54 block was also iron. Where did you read that it was alluminum?

[SilverStreak]

Yes, ruk, I was under the impression the S54 was iron also...

[rukman]

yup..sorry...s54 is cast-iron...m54 is aluminum...

m50 is iron
m52 is iron until they switched over to aluminium
m54 is aluminium

s50 is iron
s52 is iron
s54 is iron

[SilverStreak]

Cool!! Thanks for the info, that's what I thought!

[Rook]

S62 is Aluminum tho, and only weighs 6kg more than the S54. a CF hooded S62 M Coupe would be lighter than stock and damn powerful. :-) More power than davey and N/A. :-)

[SilverStreak]

S62? Which motor is that? M5 motor? Hell yeah, love to slap that in the Z3, and then put a blower on it!!

[Dark Helmet]

ummmm rukman, there is an aluminum M52 (actuall 2 IIRC)... the roadster blocks were Al. to keep the cars balanced.

the M52 B28TU Z3 blocks are higly prized in the E30 world from what I hear.

[rukman]

Originally posted by dasMafia
ummmm rukman, there is an aluminum M52 (actuall 2 IIRC)... the roadster blocks were Al. to keep the cars balanced.

the M52 B28TU Z3 blocks are higly prized in the E30 world from what I hear.

in my list i mentioned that there were m52 that were aluminium...they first started out production as iron blocks...bmw switched to aluminium later on...the U.S. introduction of the m52 aluminium block was delayed i believe because bmw was concerned with the sulfer content of U.S fuels...

[Hobbs64]

Sulfer content was a problem with the 1st gen M5. BMW had the same problem with the early 4.4 blocks. Sorry guy's I don't do BMW blocks by code. I'm a ford and Mercedes guy just getting into the BMW thing.

[SilverStreak]

I don't know half the codes, either, Hobbs, I just got into BMWs this past year, myself... I learn as I go...

[Dark Helmet]

Originally posted by Hobbs64
Sulfer content was a problem with the 1st gen M5. BMW had the same problem with the early 4.4 blocks. Sorry guy's I don't do BMW blocks by code. I'm a ford and Mercedes guy just getting into the BMW thing.

I thought it was the early 4.0 blocks that had the problem along with the late, lamented 3.0L M60?

or was "nikasil" a totally different problem?

[zenon]

So are there any Al Blocks that are compatible with the S54 Head?
ie:bolt pattern, bore spacing etc.

Any Idea how much weight they would save?

[SilverStreak]

I don't think so, I think the only compatible blocks are iron...

[rukman]

the following information is ancedotal:

interchanging heads among engine blocks hasn't really been a popular thing with modern bmw engines...not only do you run into fitment issues in terms of bolting the head onto a block it wasn't designed for but other subtleties as well...

i think i have heard of the S50 head being bolted onto an M50 block...

you might be able to bolt s52 head onto m52 block...

now if your talking cylinder head from euro engine onto a u.s. spec block...forget it...

s54 head onto any other non-s54 bottom end...forget that too...i find it highly unlikely that all the neccesary things would line up...

an interesting tidbit that crossed my mind the other day was how some people have commented on how the m54 3.0 liter engine currently used in the 330ci,330i,330ix, z3 3.0 is only rated at 225hp compared to the 3.0 liter s50 U.S spec M3 engine from a couple of years ago that was rated at 240hp...

if you look at the design of these two engines they only share displacement...the first big difference that stands out is the difference in bore and stroke...

on the s50 motor: 86.0x 85.8mm
on the m54 motor: 84x89.6mm

now add in differences in cylinder head design, intake manifold runner diameter and length and so many other variables and you have two different beasts with the same displacement...

the current progression of bmw motors on their non-M models has been a series of stroke increases sharing the same 84mm bore that m50 2.5L engine had back when it was first introduced with the e36 3 series model line...

m50 2.5 liter, 75mm stroke
m52 2.8 liter, 84mm stroke
m54 3.0 liter, 89.6mm stroke

my first question to someone who is thinking about trying to mix and match different cylinder heads to their bottom end or vice versa is...what is your aim in doing so?

[SilverStreak]

Great break down, ruk!

[Hobbs64]

The reason we got into this mix and match debate is because I now own a very low miles s54 drive train...and I have the stroker motor we were discussing the other day. The stroker motor was very expensive to design and build and the s54 motor should make the same power. The top end of the s54 is light years ahead of the m50. I simply wanted the best of both worlds, but cannot have it. So the question remains do I swap in the new s54 drive train and sell the stroker or vice verse. Help?

[Dark Helmet]

badm is right... I've just been talking about TUs a lot lately and got ahead of myself. however, the block itself is not different IIRC, so the bottom end would still work... and I believe the TU was only the '00 engines? that is the only "2.3" TU, and I was under the impression that the 2.8 was on the same schedule.

keep the stroker if it is really that well built, teh chances of that S54 having a reduced lifespan due to the wreck is high in my opinion... however, it will be cheaper to repair.

all in all, I'd keep it for when you blow the stroker!

[rukman]

Originally posted by Hobbs64
The reason we got into this mix and match debate is because I now own a very low miles s54 drive train...and I have the stroker motor we were discussing the other day. The stroker motor was very expensive to design and build and the s54 motor should make the same power. The top end of the s54 is light years ahead of the m50. I simply wanted the best of both worlds, but cannot have it. So the question remains do I swap in the new s54 drive train and sell the stroker or vice verse. Help?

well you have to weigh how much you've spent on the engine vs how much you might recover by selling it or parting it out...also take into account labor for installing the s54...

the s54 engine is nice with the 7600rpm redline, etc...but compared to your motor the hp and tq curves are very different...

i'm sure your stroker motor has a hell of alot more low end tq compared to the s54...

i like the s54 alot but i'd be inclined to part out the s54 along with the rest of the car and supercharge your stroker motor...but then again...that s54 is nice isn't it

talk about tough choice