m54?

[London]

Haha well I appreciate all the info. Yeah this is definitely for a DD car. Just want it to be fun and quick. I like the mpg benefits, I know my friends 330ci got decent gas mileage when he wasn't driving like a cock but yeah hah. I guess we'll see what happens. His car got rearended pretty bad the other day so he's trying to decide if he wants to rebuild it (though we've heard e46 rear subframes are sketchy and easily damaged) or just part it.

[Elysian]

i over reved my M52 once i think it hit about 8k with a little too early of a down shift had a little lifter tick that went away ;) lol

I accidentally rev'd my 84 RX7 to 11-12k because the throttle got stuck and it didn't have a rev limiter That was pretty damned scary It went WAY the hell past the top of the rpm gauge.

[bloodshot-e30]

i over reved my M52 once i think it hit about 8k with a little too early of a down shift had a little lifter tick that went away ;) lol

[Elysian]

Should have elaborated more.

Local M52 GTS2 car is spinning to 7500rpm with AA headers/tune/intake and stock cams, making ~200whp. Bone stock internals as I recall.

Sunbelt used to sell (via bimmerworld) a kit for the S50 that would redline at 7600rpm for race use with upgraded lifters. It got pulled off the market when people tried to use the 7600rpm redline with S52s and ate motors. S50s are happy to rev that high briefly, S52s are pretty much unable to go above 7200 without major problems. Both cases with upgraded lifters.

VE is another matter entirely, there's no point on stock intake/exhaust/cams to go above 7k. My point is that you CAN go that high if you want without building the hell out of the motor. M54, not so much, just ask Vorshlag.

Vorshlag is using my old white 330ci for their LS1 swap :) They're also putting another M54 into the blue E46 track car. The most recent motor snapped the oil pump shaft from an overrev, but yes, the oil pump shaft is pretty weak, but there are options out there. You can also install an ATI damper to fix the harmonic damper issue. Also, aftermarket isn't as big of an issue if you're running a swap, since you have the ability to tune the swap(especially with Steve's VANOS/DISA controller) and things like headers can be taken straight from an M52/S52. Hell, I'll likely turbo mine at some point using an M52/S52 cast iron manifold.

Now if you want to cam the M54, it gets a bit more pricey, unless you just go with ZHP cams, but that's not a huge gain.

[nando]

I get your point, I just thought it was funny that the S50/S52 are "high rpm powerhouses." :p

personally I'd think you'd have to be nuts (or rich) to turn any of them much above 7k for extended periods of time.

[Bimmerman325i]

Exactly. M54 is the better DD motor, S5x is the better autox/track-oriented motor.

[hoveringuy]

The M54 has a couple of problems compared to the S50/S52. The head doesn't flow nearly as well so while the intake in general is very good, it just can't sustain power over 6k rpm. The damper is known to slip/fail in track use. The archilles heel seems to be the oil pump input shaft which will sheer due to harmonics at sustained high rpms.

So, it's not that the S50/S52 is that much more powerful at high rpms, but much more reliable.

M54, on the other hand, has an awesome torque curve thanks to the extra VANOS range and particularly the DISA, which is fantastic. Weight is around 45-50lbs less than an iron block. Finally, aluminum is shiny and just looks cool.

And I'm coming up on 3 years of M54 service!

[Bimmerman325i]

what? really? bone stock to 7500+? what happens when your lifters bleed out and collapse? also what happens when your VE falls off a cliff at 7000rpm?

Should have elaborated more.

Local M52 GTS2 car is spinning to 7500rpm with AA headers/tune/intake and stock cams, making ~200whp. Bone stock internals as I recall.

Sunbelt used to sell (via bimmerworld) a kit for the S50 that would redline at 7600rpm for race use with upgraded lifters. It got pulled off the market when people tried to use the 7600rpm redline with S52s and ate motors. S50s are happy to rev that high briefly, S52s are pretty much unable to go above 7200 without major problems. Both cases with upgraded lifters.

VE is another matter entirely, there's no point on stock intake/exhaust/cams to go above 7k. My point is that you CAN go that high if you want without building the hell out of the motor. M54, not so much, just ask Vorshlag.

[nando]

what? really? bone stock to 7500+? what happens when your lifters bleed out and collapse? also what happens when your VE falls off a cliff at 7000rpm?

[Bimmerman325i]

hahaha, the S50/S52 US motors are high-rpm power houses? are you high?

M54 = S52 with an 84mm bore and aluminum block. Oh, it also has double, variable vanos.

None of these motors are high rpm powerhouses either.. they're all M50 strokers with slightly upgraded cams.

Compared to an M54, yes, an S50/2 US is. Compared to a Euro or S54, hell no.

My point is that US S5x motors can happily rev 700-1100 rpm higher, which yields more power than an m54 that eats itself above stock rev limit.

You can spin an M52 to 7600rpm all day long, and an S50 US to 7400/7500. Try that in an M54 and it will just die.

[nando]

hahaha, the S50/S52 US motors are high-rpm power houses? are you high?

M54 = S52 with an 84mm bore and aluminum block. Oh, it also has double vanos with variable output.

None of these motors are high rpm powerhouses either.. they're all M50 strokers with slightly upgraded cams.

[Bimmerman325i]

What's so fragile about an M54 if you're not boosted to 400+ hp? If you're doing an engine swap you're going to address the oil pump nut issue when you do the oil pan swap and should probably baffle the pan to begin with, M54 also uses the same crank as the S52, and plenty use the M54 on the track with little to no issue...

Wrong. Read Vorshlag's thread on their DSP 330Ci. They blew two motors because the M54 CANNOT handle >6500rpm race use without eating itself. It is known to be super fragile for track use naturally aspirated without fully building it. The aluminum block is nowhere near as stiff as the cast iron M/S50/2 blocks, and as a result the vibration issue from the S52 crank is greatly magnified in the M54. It's a poor choice for a race motor unless you are constrained by rules. Furthermore, the aftermarket support is very little, so while hoveringuy made ~230whp with cams and tune and supporting mods, a CAI and tune alone on an S50 will make that power because it can rev higher without issue.

Now, for a street car, that doesn't matter. Keep the rev limit stock and it will be happy forever. It is not a high rpm powerhouse like the S5x is, so as long as you respect the motor's limits, it will be fine. I would NOT choose one for an autox or track oriented car though, especially for an E30 swap. For a DD I think it would be a great motor since it is torquey down low.

[Elysian]

Yes, an M54 swap has been thoroughly documented by hoveringuy, and if you actually read his posts, you'd have seen that the car has been finished and driving for over a YEAR.

Is it better than an S50? Opinions are like assholes, everyone has them. For track use, hell no (M54 is much more fragile). For DD/fun? I think they'd be about even. S5x has much better power potential for the dollar though, but that might not matter. It should get better fuel economy and has more torque down low in the rpm band.

What's so fragile about an M54 if you're not boosted to 400+ hp? If you're doing an engine swap you're going to address the oil pump nut issue when you do the oil pan swap and should probably baffle the pan to begin with, M54 also uses the same crank as the S52, and plenty use the M54 on the track with little to no issue...

[Bimmerman325i]

Yes, an M54 swap has been thoroughly documented by hoveringuy, and if you actually read his posts, you'd have seen that the car has been finished and driving for over a YEAR.

Is it better than an S50? Opinions are like assholes, everyone has them. For track use, hell no (M54 is much more fragile). For DD/fun? I think they'd be about even. S5x has much better power potential for the dollar though, but that might not matter. It should get better fuel economy and has more torque down low in the rpm band.

[Court M3]

I've driven Hoveringuy's car and to tell you the truth it was more than enough get up and go! Scary quick!!