E36 M3, from dual purpose to track only

[aeronaut]

EEEK...50lbs extra sucks! I hate adding weight.
But Yea, made final decision today. Not going S54 route. I've gone through that thought process several times now. lol.
S50 FTW, it'll keep me in the same TT class I run in twice a year. lol. And found a good one local. Looked at it today ,picking up tomorrow.

[aeronaut]

No looking good for the head. Popped the spark plug out from the kaboomed cylinder.

IMG_20211019_163718.jpg

Looking into cylinder with inspection camera
IMG_20211019_164100.jpg

[aeronaut]

I have now talked to 2 shop owners who have personally witnessed failure of the S54 setup + VAC modified oil pump. One shop owner installed this system in an S52 race engine, and it spun a bearing within 2 sessions. The other said that the VAC modified pump failed. Plus, my experience.

For clarity, looking back at data, I had significantly reduced oil pressure (as low as 15PSI) under any sort of lateral or braking G's.

After experiencing mine, talking to the first shop owner (who experienced 1, and had heard of others), and then talking to the 2nd shop owner who knows of one, I feel compelled to report.

[olemiss540]

Wow. Just wow. Love my accusump even more now....

[aeronaut]

Wow. Just wow. Love my accusump even more now....

Yep! Im shopping sumpys now. What size you using? Manual or other valve?

[hoki06]

Your experience sounds similar to my old race car. I installed a stock S54 pump/pan and had single digit OP numbers both on track and coming off track hot. I can vividly remember pulling into the paddock at VIR and seeing 7 psi with the clutch in and idling. I had to keep RPMs over 1k because hot idle OP was so low that it terrified me. I ended up going back to a stock S52 pump/pan and pressures were perfect.

[GrifM3]

Sorry to hear about the bad luck. Just another data point, I have the VAC hardened shaft and sprocket installed in a stock euro dual pickup pump on my highly modified S52. Over 35K street miles and multiple track days with regular pulls over 7500 RPM, with no issue to date. I don't have any data logging capabilities, but do have an oil pressure gauge, which I watch religiously on track and I have never witnessed any pressure issues since the swap.

If it were me in your situation, I'd be going S54. So much more potential for performance. But, certainly not an inexpensive swap. With best in class tuning, guys are regularly getting 360whp from the S54 with no internal mods, other than cams.

[olemiss540]

Yep! Im shopping sumpys now. What size you using? Manual or other valve?

I dont have a passenger seat so I mounted a Moroso 3 QT sump in the passenger footwell with a manual valve I can turn on/off every time I start her up. My brother has an accusump (3QT) with an automated valve with the tank mounted across the front bumper beam believe it or not.

[aeronaut]

Thanks, good info. Friend is about to buy the 3qt Moroso for his 135i.
I want to use the manual valve, but would prefer to keep some sort of passenger ability (although rarely used), so I'll have to figure out how to get it close. Maybe under the dash where the HVAC used to be.

[aeronaut]

Sorry to hear about the bad luck. Just another data point, I have the VAC hardened shaft and sprocket installed in a stock euro dual pickup pump on my highly modified S52. Over 35K street miles and multiple track days with regular pulls over 7500 RPM, with no issue to date. I don't have any data logging capabilities, but do have an oil pressure gauge, which I watch religiously on track and I have never witnessed any pressure issues since the swap.

If it were me in your situation, I'd be going S54. So much more potential for performance. But, certainly not an inexpensive swap. With best in class tuning, guys are regularly getting 360whp from the S54 with no internal mods, other than cams.

I've considered it, and am convinced to do it right (make reliable for track) it's a $10k or more swap.

[aeronaut]

Damn it, the S50 I looked at, is actually an OBD1 S52.
Or. Hmmm.

[mslevin]

Why's that bad? More powaahh

[aeronaut]

Yea, I loved my unloved S50, but those have become quite hard to find, so S52 and I'll keep my red line at 7k I guess. 😄

[golgo13]

I just read about the motor, sorry man!

If it makes you feel any better my freshly rebuilt S54 exploded on the second lap of my first session on Saturday 10/10.

[aeronaut]

Fvck!!! Sorry man, that hurts.

[golgo13]

Fvck!!! Sorry man, that hurts.

Well, it was a great learning process lol

Hope you get your motor sorted soon!

[aeronaut]

What caused your explosion?

[golgo13]

What caused your explosion?

It's complicated but the machine shop that did the head refresh left out the set screw for the exhaust cam follower shaft. The head got some damage which we repaired, but metal circulated throughout the block which was causing some strange high oil pressure. The car survived 15 dyno runs, but couldn't handle a single track day haha.

[aeronaut]

Pulled engine, head and oil pan off.
Nothing visually wrong with S54/VAC Oil Pump sprocket, or S54 pickups.
Con rod is intact (but bent), so that wasn't the failure.
It sure looks like a broken valve, but that doesn't explain at all the quirky oil pressures for 2 events prior.

IMG_20211023_171433.jpg

IMG_20211023_171425.jpg

IMG_20211023_171331.jpg

[aeronaut]

And, here we go. S52 with OBD1 conversion, freshly out of a running car from a shop. The only issue is unknown mileage (cause swap). Leak down #'s look great, all under 10%.

IMG_20211025_135649.jpg

[olemiss540]

Looks clean! Any compression numbers? What are you planning to do with the oil pump/pan setup?

[aeronaut]

No compression numbers, just leak down.
I'm not reusing the S54/VAC setup. I might send the pump back to VAC for inspection, and then sell it. The pan has a small piece of an inner rib broken from the explosion, so while I'd use it, it's probably not worth much.

Going with, you guessed it, accusmpy! Plus oil pan baffle. And maybe a new or rebuilt stock oil pump (but OEM new is $500.)

And, pondering again, new higher compression pistons or not.

[olemiss540]

Wait waaaaa? You going to pull this perfectly functioning motor apart for oil pump and potentially pistons?!?

I say slap it together and run but shows you how lazy I am. KISS usually ends up the most reliable in the end.... No way am I going to tell ya told u so on the accusump. Not after the pain you went through :-)

Also, if it makes you feel better mine has been in the shop for 2 weeks trouble shooting a wiring issue with my LS swap that has taken me down 3 events in a row. So I guess I don't heed my own advice.

[aeronaut]

Ha! Oh, I heard you the first time I just didn't listen.

Honestly, I can't put all the pieces together to know what really happened to my engine. From data and break down, momentary loss of OP in higher G situations, broken valve. Hard to see how those go together. So there's that.

Are you saying, you wouldn't at least pull the head and refresh and do head gasket on an engine that has at least 140k mi?
I have all winter, is the problem.

- - - Updated - - -

Wait waaaaa? You going to pull this perfectly functioning motor apart for oil pump and potentially pistons?!?

I say slap it together and run but shows you how lazy I am. KISS usually ends up the most reliable in the end.... No way am I going to tell ya told u so on the accusump. Not after the pain you went through :-)

Also, if it makes you feel better mine has been in the shop for 2 weeks trouble shooting a wiring issue with my LS swap that has taken me down 3 events in a row. So I guess I don't heed my own advice.

Oh, shit, shop time ($$$) chasing an electrical daemon...sorry to hear that!!!

[olemiss540]

Pulling the head for a refresh is one thing but these lower ends are stout so when you start fiddling with lower end bearings/pistons/etc I get a bit more nervous first session next year doesn't go as planned....