What is the specific difference between an m52 and S52?

[clydesdale]

I have searched numerous threads. I realize the s5x is out of the M cars and have higher HP. What I am specifically interested in is figuring out if it pays to get an m5x and then mod it. What makes an "s" an "s"? What is different about the motors in the M cars. The eventual goal is still a 24v swap. I am trying to find out what will be the best mix of reliability, driveablility and power? Thanks

[Wh33lhop]

The difference? Bore, stroke, cams, valve springs. That's about it. The european S50s are different, but US got stuck with the spruced up M50/M52s.

[triggrhaapi]

M50 to S50 is bore/stroke/cams.

[dranttna]

keep in mind the larger liter size means thinner cylinder walls. there was a site that had the motor blueprints for all s/m5x but i cant find it now, ill add it later

[clydesdale]

That would be great. I am looking for the blue prints. I am trying to determine if I should go for a cheaper m52 and modify it with the cams or if I should just source an s52. Thanks

[Adrian_Visser]

This has been discussed many times. The consensus is that you will end up spending more money on mods bringing the m50/52 up to s50/52 specs than buying the S5x outright, unless you do a budget turbo build, but then reliability may be suspect.

[clydesdale]

Thanks man. Sounds like I will stick with the s52 plan. For a motor with 75k miles is $2700 the going rate? If not can you give me an idea as to what I should expect to pay. Thanks.

[MikeDE]

The difference? Bore, stroke, cams, valve springs. That's about it. The european S50s are different, but US got stuck with the spruced up M50/M52s.

Very few would have paid $60K for an M3 in the 90's, consider too that the E30 M3 was about $32k and many of them collected dust on lots for quite a while. Hell, nobody even wanted to pay for an M3 LTW, granted it was bare-bones. They sat around too. There just wasn't enough enthusiasm over them, today is a different story. Also, the mid-late 90's saw the death of many a 'super'car. Supra TT, 300ZXTT, RX7, 3000GT VR4, Eagle Talon TsiAWD/Eclipse GST/GSX.....

[87e30]

This has been discussed many times. The consensus is that you will end up spending more money on mods bringing the m50/52 up to s50/52 specs than buying the S5x outright, unless you do a budget turbo build, but then reliability may be suspect.

I would expect to pay around 1000 for cams/MAF/tune on an m52 which should do the trick? (s5x are probably about that much more than m5x so seems comparable?)

Personally, I love the feel of cams in an m52, really calm engine until you get on it and the power kicks in up top. It's a lot of fun in my opinion.

Granted I haven't driven an s5x car.