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
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.
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.
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.
At what age or mileage should an S52 be "freshened up"?
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
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.Originally Posted by M3Express
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.
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
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.
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?
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.
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
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
You should be plastigauging your clearances regardless of whether you use ARP or OE...
ARP i dont think is a justified cost in this
98 Estoril ///M3 4/6
S54 swap CSL
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.
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