Results 1 to 19 of 19

Thread: Rebuilding an S52

  1. #1
    Join Date
    Jan 2011
    Location
    PA, USA
    Posts
    328
    My Cars
    1993 325i S52 Modded

    Rebuilding an S52

    Got an S52 engine that's supposedly a 99 and only has about 90k on it. Right now it's in a 94 525i and I'm gonna swap it into my 93 325i. But before I do that I want to rebuild it. Nothing crazy but possibly a supercharger down the road and I don't want the engine to blow up if I do it.

    I'm already plannin on:
    New vanos
    water pump
    t-stat + metal cover
    rod bearings
    pistons, rings
    valve springs
    cam chain + timing chain
    primary and secondary tensioners
    oil pump



    so I'm just curious as what else you guys think I should replace? also what kind of pistons? And What kind of headgasket? And I'm assuming oem valve springs will be fine.

    Thanks
    Be A Baller: Go To The Dealer For Everything

    Yay, the BMW crowd has now joined the VW crowd with the "Watch us do stupid things!" mentality.
    Quote Originally Posted by Joylove View Post
    Glovebox and centre console. Both as much use as tits on a fish.

  2. #2
    Join Date
    Mar 2004
    Location
    Brooklyn
    Posts
    3,129
    My Cars
    97 M3, 65 Mustang FB
    When I pulled my head apart at 145K, I planned to replace the chain and guides. They looked brand new. And I just rebuilt the Vanos. Works fine.

  3. #3
    Join Date
    Jan 2011
    Location
    PA, USA
    Posts
    328
    My Cars
    1993 325i S52 Modded
    It's more like a "while it's out" kind of thing. And I don't know the history or maintenance of this engine so I don't want to do all the work to put it in and then have to pull it back out a couple months later cause something breaks.
    Be A Baller: Go To The Dealer For Everything

    Yay, the BMW crowd has now joined the VW crowd with the "Watch us do stupid things!" mentality.
    Quote Originally Posted by Joylove View Post
    Glovebox and centre console. Both as much use as tits on a fish.

  4. #4
    Join Date
    Jan 2011
    Location
    reno, nv
    Posts
    91
    My Cars
    1994 325is/m3 converted
    if anything i would just freshen up the top end. valve job, new valve seals and maybe guides. a valve job or even just lapping the valves will add a few hp.

  5. #5
    Join Date
    Aug 2011
    Location
    Miami, FL
    Posts
    28
    My Cars
    99 M3 Vert|08 Cayenne S
    At what age or mileage should an S52 be "freshened up"?

  6. #6
    Join Date
    Nov 2010
    Location
    portland, Oregon
    Posts
    4,490
    My Cars
    1998 m3 coupe, 68 FJ40
    You would be mad to do pistons at 90k. Just pull the head, and send it in to be checked. replace the gasket with the appropriate one for boost and put in arp's. Done

  7. #7
    Join Date
    Mar 2009
    Location
    NH/DC
    Posts
    734
    My Cars
    98 M3
    Quote Originally Posted by M3Express
    At what age or mileage should an S52 be "freshened up"?
    IMO, I wouldn't consider freshening up anything south of the valve cover gasket until the head has to come off for some other reason (HG failure)...And you can't really put a mileage number on that, too many variables.

  8. #8
    Join Date
    May 2004
    Location
    Florida Panhandle/ Ohio
    Posts
    7,318
    My Cars
    14 JGC/13 E88 128i
    If you want to know what to do regarding rebuild visit the FI section in this forum. If you plan to supercharge or turbo charge now is the time to lower that compression ratio.
    That can be done with pistons.

    Regarding rebuilding it.
    Why?
    I pulled the head on my 274K mile M3 engine because I wanted to freshen the top end. It was a waste of time but while I was in there I rebuilt the VANOS which by the way worked fine even with an O ring as hard the seal, installed newer valves and new springs with new seats.

    I would consider 90K miles if treated well to be a great engine to reinstall.
    Best advice I could provide is to make sure the starter is new or in excellent shape, change all the heater hoses while you have it apart since the starter and the hoses are a pain to change without pulling the manifold.
    Last edited by fun2drive; 08-12-2011 at 10:15 PM.

  9. #9
    Join Date
    Dec 2007
    Location
    Rochester, NY
    Posts
    531
    My Cars
    97 M3/2/5 - 96 9k Aero
    I've been doing research for my own headgasket job which I am working on right now. I was told the Elring HG was the best one to get. However, I posted a lot more information regarding my research - and upgraded head gaskets, I'll also mention the ARP 2000 head studs (which I don't think I'll be purchasing for my job, but you may want for FI?? I'm still not sure on this one), but see this link for the info I gathered:
    http://forums.bimmerforums.com/forum....php?t=1696164

  10. #10
    Join Date
    Jun 2005
    Location
    New England
    Posts
    25,402
    My Cars
    F90 M5; E36 M3 Turbo
    I would use the ARPs if running an MLS gasket to lower CR. If not running an MLS, I would run the Elring gasket with stock bolts. MLS have had some sealing issues so there is some risk and the risk is probably greater the thicker the MLS. More clamping force is the way to go, but even then there have been occasional sealing issues. It is up to you whether to take the risk. Rebuilding with lower CR pistons is many times more expensive. I have run a thicker MLS for 5 years in two different engines, with a centrifugal supercharger and a turbo, and ARP studs.

    Another way to go is a copper HG spacer and gasket. CES sells these. They claim to have very good results. Not as many are in use as the MLS. The cost is greater. I would have no concerns about trying one.

    Before lowering your CR, figure out what you might run. A centrifugal supercharger does not need lower CR because it produces so little boost at peak cylinder pressure. If peak boost is 9 psi at 7000 rpm, it will make about 3 psi at 3500 rpm. The 9 psi turbo will be making 9 psi at 3500 rpm. A twinscrew supercharger will make its 9 psi maybe as low as 2000 rpm. People disagree about when CR needs to be dropped for a turbo or twinscrew. I would say above about 8 psi or 350 rwhp. Some have pushed that to 10 psi and 400 rwhp, but longevity be compromised. And at some point with a centrifugal, CR should be lowered. I dropped mine when going over about 13 psi (used a 0.098 MLS and ran 16 psi via a Vortech T Trim and this gave me about 4 psi at 3500 rpm -- which was not exciting enough in the midrange so I am now running a turbo with a 0.140 MLS and make 15 psi at 3100 rpm in 5th gear).
    Last edited by pbonsalb; 08-13-2011 at 08:44 AM.

  11. #11
    Join Date
    Jan 2011
    Location
    PA, USA
    Posts
    328
    My Cars
    1993 325i S52 Modded
    wow that's alot all at once. Thanks. If/when I go SC. My goal is about 300whp. So I don't want to lower my compression and i'm leaning toward the mls HG and the arp studs.

    with the way everyone is talking, it seems like I don't even need new pistons, but I will atleast re-ring it. Wheres a good place to get quality rings? Wiesco?
    Be A Baller: Go To The Dealer For Everything

    Yay, the BMW crowd has now joined the VW crowd with the "Watch us do stupid things!" mentality.
    Quote Originally Posted by Joylove View Post
    Glovebox and centre console. Both as much use as tits on a fish.

  12. #12
    Join Date
    May 2014
    Posts
    114
    Quote Originally Posted by pbonsalb View Post
    I would use the ARPs if running an MLS gasket to lower CR. If not running an MLS, I would run the Elring gasket with stock bolts. MLS have had some sealing issues so there is some risk and the risk is probably greater the thicker the MLS. More clamping force is the way to go, but even then there have been occasional sealing issues. It is up to you whether to take the risk. Rebuilding with lower CR pistons is many times more expensive. I have run a thicker MLS for 5 years in two different engines, with a centrifugal supercharger and a turbo, and ARP studs.

    Another way to go is a copper HG spacer and gasket. CES sells these. They claim to have very good results. Not as many are in use as the MLS. The cost is greater. I would have no concerns about trying one.

    Before lowering your CR, figure out what you might run. A centrifugal supercharger does not need lower CR because it produces so little boost at peak cylinder pressure. If peak boost is 9 psi at 7000 rpm, it will make about 3 psi at 3500 rpm. The 9 psi turbo will be making 9 psi at 3500 rpm. A twinscrew supercharger will make its 9 psi maybe as low as 2000 rpm. People disagree about when CR needs to be dropped for a turbo or twinscrew. I would say above about 8 psi or 350 rwhp. Some have pushed that to 10 psi and 400 rwhp, but longevity be compromised. And at some point with a centrifugal, CR should be lowered. I dropped mine when going over about 13 psi (used a 0.098 MLS and ran 16 psi via a Vortech T Trim and this gave me about 4 psi at 3500 rpm -- which was not exciting enough in the midrange so I am now running a turbo with a 0.140 MLS and make 15 psi at 3100 rpm in 5th gear).
    My engine is at 200k I'm rebuilding the heads, would I be okay with some stock elring HG and just some ARP? Or should I just get the CES cutring HG? TIA

  13. #13
    Join Date
    Jun 2011
    Location
    Vancouver, BC Ca
    Posts
    3,255
    My Cars
    1993 325is
    This thread is over 6 years old. It'd be far more helpful to know what you're planning for the motor. If it's just NA, then you don't need cutring or anything else fancy (not even ARPs). If you're planning forced induction, I suggest you go spend some time in the forced induction forum and do some searching. There's literally tons of info about this exact thing.

  14. #14
    MauiM3Mania's Avatar
    MauiM3Mania is offline Observer/Master Skeptic Moderator
    Join Date
    Jan 2002
    Location
    Central Pacific
    Posts
    10,809
    My Cars
    88M3 99M3 04M3 ITBx16
    04M3 TiAg 69k slick-top 3 pedal
    99M3 Cosmos 61k S50B32 euro 6Spd

    88M3 AW 43k miles Project FS


    WTB: 3.5" Eurosport/Conforti CAI

  15. #15
    Join Date
    Jan 2002
    Location
    outta SoCal, now CO
    Posts
    1,212
    My Cars
    '98 M3 Alpine White
    Old thread, but be careful if switching to ARP hardware. ARP stuff clamps tighter than stock and will distort cylinders, main bearing bores and rod bearing bores beyond factory tolerances. You need to plan for that during assembly. I've had crankshafts that spun easily with two fingers with stock main cap bolts only to lock up tight after installing the ARP studs. Line honing was in order. Same with rods. Varying distortion of the rod bearing bore of up to .0015 over factory specs requiring machining and fitting of each rod separately with ARP bolts. Cylinders need to be bored/honed with a torque plate AND the ARP studs in place. This is from S52 assemblies. I do my own machining and assembly. I've also been to the ARP manufacturing facilities in Santa Paula and watched everything from raw materials to finished nuts, bolts and studs. They make the best but you will shorten the life of your engines to varying degrees if you don't plan for the upgrades.
    See ya later,

    tony
    '98 M3, '92 Dinan3, '05 R1100S BCR, '07 R1200S, Aprilia T

  16. #16
    Join Date
    Jun 2011
    Location
    Vancouver, BC Ca
    Posts
    3,255
    My Cars
    1993 325is
    Quote Originally Posted by tjm3 View Post
    Old thread, but be careful if switching to ARP hardware. ARP stuff clamps tighter than stock and will distort cylinders, main bearing bores and rod bearing bores beyond factory tolerances. You need to plan for that during assembly. I've had crankshafts that spun easily with two fingers with stock main cap bolts only to lock up tight after installing the ARP studs. Line honing was in order. Same with rods. Varying distortion of the rod bearing bore of up to .0015 over factory specs requiring machining and fitting of each rod separately with ARP bolts. Cylinders need to be bored/honed with a torque plate AND the ARP studs in place. This is from S52 assemblies. I do my own machining and assembly. I've also been to the ARP manufacturing facilities in Santa Paula and watched everything from raw materials to finished nuts, bolts and studs. They make the best but you will shorten the life of your engines to varying degrees if you don't plan for the upgrades.
    This is very true. I've preached this many times over the years. I've always heard the naysayers say "it's fine, I went 20,000 miles without any issues". But the engineering and metallurgy say that distortion is very real and can lead to issues.

  17. #17
    Join Date
    Feb 2012
    Location
    Birmingham, Alabama, USA
    Posts
    8,369
    My Cars
    1995 BMW M3
    You should be plastigauging your clearances regardless of whether you use ARP or OE...

  18. #18
    Join Date
    Sep 2007
    Location
    UT
    Posts
    4,375
    My Cars
    98 M3/4/5
    ARP i dont think is a justified cost in this
    98 Estoril ///M3 4/6
    S54 swap CSL

  19. #19
    Join Date
    Jan 2002
    Location
    outta SoCal, now CO
    Posts
    1,212
    My Cars
    '98 M3 Alpine White
    Quote Originally Posted by TH3 Shifty View Post
    ARP i dont think is a justified cost in this
    Not sure this is even a factor. How much of ANY of this can we really justify, anyway?

    And, after watching the ARP stuff in the making and seeing all the bins for the race team stock I'd buy'em just to hang on the wall as art.
    In fact, here's a couple of desktop backgrounds.
    Attached Images Attached Images
    Last edited by tjm3; 03-27-2017 at 08:11 PM.
    See ya later,

    tony
    '98 M3, '92 Dinan3, '05 R1100S BCR, '07 R1200S, Aprilia T

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •