S50B32 claimed by Mount Panorama (Bathurst)

[Kthree]

In what can be called an 'eventful' weekend in the annual Mount Panorama/Bathurst Challenge, it's the S50B32's time for drama! There was plenty of Porsche fatalities, so i came off lightly in comparison

Preliminary cause looks like a dropped valve seat (only 20hrs run time since that was done) jammed a valve which made connection with piston. Haven't cracked her open yet, however the Emtron KV8 (DME) data shows cyl2 was the culprit, and sure enough removing cyl2 plug the next day confirmed the absolute carnage unleashed in there. The KV8 was *extremely* quick in limiting timing, dumping in fuel and trying to keep it under control which is a hard ask with mechanical failure, very impressed with how fast it gets into save-the-engine-mode, in the low millisecond range. Bear in mind it has bosch flat response knock sensors that picked this noise up

As for sequence of events i was coming into the very fast downhill, concrete walled, blind cornered, no runoff 'Esses', so it was either stop/coast/neutral and risk a car run into the rear (common occurrence) or just ride it out until i could get off

Watch the rear view footage; it's still full of oil and water, thats just fuel pouring out - lambda only reads to .5 however i think DME just pumped it in as part of its strategy

https://www.youtube.com/watch?v=LQOzFkKqZ3c

And previous session that the grid order was totally messed up hence the traffic, so still 10secs off

https://www.youtube.com/watch?v=EqwnCV-gbX0

Guess it's engine build time, at a minimum head and pistons/rods, see how she looks when i pull her down in the next few weeks

[MParallel]

Ah tough luck man.

Bathurst must be nice. I only know it from playing Real Racing 3 on mobile.

[Jim E.]

Lousy luck. Keep us posted.

[jayson]

Dang that sucks! Spend enough time on the track though and it is bound to happen I suppose.

That is a great camera / track app setup you are running - have any details on it?

[Kthree]

Yeah to be expected after 12yrs, will update this thread as i go through the rebuild

That is a great camera / track app setup you are running - have any details on it?

Lots of elements, and can be fiddly to sync;

Racerender 3 - made my own profile and gauge styles etc
GoPro 3+ x2
Emtron ECU logging - Engine
ECUMaster ADU logging - GPS/Timing/Tyres (CAN)

Might add a brake pressure transmitter purely for logging instead of just the pedal switch during this exercise, some blanked ports on the MC i'll investigate further

[Steage]

Painful to see.

I've been struggling to master Mt. Panorama in GT7, I'd love to try it in real life.

In the video game I've never really had to think about how there's no where to pull off the track in that section, must make cleanup a hassle.

[jayson]

Painful to see.

I've been struggling to master Mt. Panorama in GT7, I'd love to try it in real life.

In the video game I've never really had to think about how there's no where to pull off the track in that section, must make cleanup a hassle.

Haha yes, lots of narrow bits for sure. I enjoy it in the E30 Sport Evo. Perhaps one day Polyphony will stop releasing 50x versions of GTR's and put in a proper E36.

[Kthree]

I've been struggling to master Mt. Panorama in GT7, I'd love to try it in real life.

Funny thing is, i find it harder to play on a sim setup than to do it for real 😆

[J!m]

BUMMER! I hope you get it sorted soon.

Post the carnage photos a well, if you have the stomach for it...

And at least it died doing what it's meant to be doing!

[Kthree]

BUMMER! I hope you get it sorted soon.

Post the carnage photos a well, if you have the stomach for it...

And at least it died doing what it's meant to be doing!

Half way through teardown, it's pretty messy! This is going to be quite a few dollars, and subsequently take time to repair if/when i can get parts

I *think* what has happened is it spat a shim from rear cyl2 intake valve, thats bounced around a bit and lodged itself between bucket and shim of the forward cyl3 intake valve, shattered, then been ground up by intake cam lobe. Then a peice has lodged itself between rear cyl2 exhaust cam lobe and bucket, then spat out. Surprisingly it still ran until at some point it ground through the cam carrier on cyl3 and jammed, which consequently broke the intake cam vanos spline (between the helical and straight spline) and then the cam has just done its own thing, fusing the whole vanos cam gear assembly together as it spun. I have valves inserted sideways into the intake on cyl2 and cyl5 Still to remove head as i have to get off the exhaust headers (shit of a job) so should be impressive when i get to it

So far whats dead;

Cam carrier
Head
Pistons
VANOS intake variable gearing 'shaft' assembly
Intake cam gear/chain assembly
Many valves/seats/valve guides

Also on the list for replacement will be Rods/bearings etc as i can't guarantee their integrity with this level of stress. Will be getting shim under buckets even though i only would spin her to 7600 (deliberate soft limiter)

Repair hinges on bore and crank inspection. If it's not deemed salvageable i'll have to explore other (non cost prohibitive) solutions sadly. I love this engine, and prefer it to the S54 (cue fanboy outrage) for various reasons, so it's definitely going to be repaired if able

As i do not have photobucket or any other hosting service anymore, I'll post up pics as it goes on Instagram "thegreenm3"

[Kthree]

Bit of an update

Have core parts incoming; Block, Head, Cam carrier, intake VANOS gear assembly, pistons, rods. Nothing that broke the bank either, though everything else moving forward will be on my monthly budget so will take an estimated 10mths

First order of business will be cylinder head, almost same configuration as last time;
Supertech +.65mm nitrided Intake valves - all new
Supertech +.40mm Inconel exhaust valves - all new
Ported/blend/radius’d (RAMS CNC)
Supertech 6mm single lock conversion
Supertech Titanium Spring incl retainers/seats etc - all checked/tested serviceable
*deliberating* Catcams 1303618 from 1303614
*changed* Supertech underbucket shims, lash caps etc

Following on from that the bottom end;
OE crank/rods - all checked/tested serviceable
Pistons pending bore size requirement/clearances
Bearings - TBD
Full balance as to be expected

Where the rocker cover was damaged i will make up an aluminium "band aid" and weld that on as evidence. Might even get tricky and re-powdercoat the rocker cover (black) and have the bandaid repair the generic soft-pink colour 😂

Honestly it was running amazingly until this point, and whilst 286rwhp doesn't sound a lot, it was definately holding its own against the competition so there is little point in changing much at all

[Nate047]

Good luck! Curious to know the cost of this rebuild.

[Kthree]

Good luck! Curious to know the cost of this rebuild.

For ease i'll convert to USD. Shall be an interesting comparison not necessarily on parts prices, but labour prices between countries

In this iteration $4k on used engine 'core' parts - Block, Head, Cam carrier, VANOS intake gear/spline assembly, pistons, rods

Parts - New JE pistons, catcams, supertech valves/buckets/misc, HG/bolts/etc BMW parts around $5.5k

Labour and some mech items like bearings etc is unaccounted at this point

So yes, not cheap so will be a lengthy process. In context, even buying an LS (never on the cards anyway) here is a very expensive proposition since holden closed down and covid kicked off

[Nate047]

Yea I feel like pretty much your only two choices are rebuild the S52 or go S54.

[Kthree]

S52? This ain't no tractor engine

Everything is stupid prices now, an S54 here is easily a US$10k mystery box. Plus the S50 has a character that isn't present in an S54 (and an exhaust note that doesn't sound like ass)