Popped the block

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Davidwarren

Corporal
Nov 6, 2016
180
Louisville
So if the root cause of this problem was indeed tired rods, it would perhaps be good for others to know how much torque they had to deal with in this case. I did below virtual dyno to compare with my own tune. My car is a little faster than a stock M4 for comparison.

View attachment 31275

I don't know if the standard VD data is right for your car - I selected 335i sedan manual transmission in virtual dyno. At least the torque projection should be pretty accurate.
that seems a bit on the high side for torque. But I don't have anything to counter it with. edit- just realized that is Nm, not ft/lbs. That's probably pretty close.
 

V8bait

Sergeant
Nov 2, 2016
393
Texas
If what Asbjorn said is correct you were running way too hot of a tune for the track. These blocks lack the adequate cooling, and the oil heats up too much. If you were on e85 or meth maybe you would have survived, but generally for track setups on factory turbos 14psi with around 7.5 degrees timing is the limit to survive. On upgraded turbos that retain the factory manifolds you can barely get away with any more, maaaybe 16psi at conservative timing. The advantage of upgraded turbos is the top end, holding power, not so much adding it. N54 isn't great at the track without some significant changes unfortunately. Too much heat and the clearances tighten and you lose ring lands and pistons, too much heat or too high G of turn and oil breaks down or you lose oiling and lose a bearing/rod.
 
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Davidwarren

Corporal
Nov 6, 2016
180
Louisville
If what Asbjorn said is correct you were running way too hot of a tune for the track. These blocks lack the adequate cooling, and the oil heats up too much. If you were on e85 or meth maybe you would have survived, but generally for track setups on factory turbos 14psi with around 7.5 degrees timing is the limit to survive. On upgraded turbos that retain the factory manifolds you can barely get away with any more, maaaybe 16psi at conservative timing. The advantage of upgraded turbos is the top end, holding power, not so much adding it. N54 isn't great at the track without some significant changes unfortunately. Too much heat and the clearances tighten and you lose ring lands and pistons, too much heat or too high G of turn and oil breaks down or you lose oiling and lose a bearing/rod.
Eh, it held up for 5 yrs as a track car. It happens.
 

Bnks334

Sergeant
Dec 1, 2016
391
New York
Honestly seriously considering an ls3 swapped in.
You gonna dry sump the ls3? You think it will run any cooler or eat any less cash? Just asking... n54 engines are cheap enough to drop in a new one vs going through all the hidden costs of an engine swap.
 

rac

Corporal
Nov 14, 2016
127
Australia
I reckon if you planned on sticking with the car over the long long run, then the swap would probably pay dividends.
If you got another 5 years out of a basic n54 set up then that seems like the cheapest way forward?
 

Davidwarren

Corporal
Nov 6, 2016
180
Louisville
You must mean with a brand new crate motor and t56 transmission, right? I think you should easily be able to go ls swap for less than 15k is you used a junkyard motor.
Quality pullout ls3 with manual is around 8k, stand-alone ecu and harness 1500, dry sump 4K, custom exhaust and drive shaft work... it adds up.
 

fmorelli

Brigadier General
Staff member
Aug 11, 2017
2,516
Virginia
@V8bait mentions the factory manifold ... heatwise I wonder how the stock head, known to be rather constrictive, factors into the heat equation.

Filippo
 

Dream_Racer

New Member
Sep 22, 2019
5
I've been day dreaming of doing an ls swap for a few years now. Big displacement, t56 magnum, ford 8.8 diff. The real hang up for me is the power potential of the n54. 5-600whp is very doable for a track car. Also fairly easy for an ls. Going to need a fairly stout setup though to be reliably pushing those numbers n/a. Stock t56 probably isn't the best bet. The swap would basically come down to cooling ability, better weight distribution and the crazy aftermarket for ls engines. Power isn't really an issue on this platform. Not sure I would go through all that trouble to drop in 430bhp. Like you say, it adds up quickly though. We just don't see the crazy power gains other chassis do, that make it a no brainer. I still want to do it, and I likely will at some point. Would love to see you do it, or anyone that's not doing it for drift or drag racing.
 

Asbjorn

Sergeant
Mar 10, 2018
467
Europe, based in China
So just to add in my findings posted in the accusump thread. Even I now have a baffle simiar to OPs, my oil pressure still drops from an indicated 90-100psi to around 60psi on left hand turns when trail-braking with michelin cup 2. On faster left handers, without trail braking first, the drop is only an indicated 80-90psi. Right handers never show signs of oil pressure dropping.

Take these numbers as relative indicators.
 

MoreBoost

Corporal
Jul 27, 2017
223
So if the root cause of this problem was indeed tired rods, it would perhaps be good for others to know how much torque they had to deal with in this case. I did below virtual dyno to compare with my own tune. My car is a little faster than a stock M4 for comparison.

View attachment 31275

I don't know if the standard VD data is right for your car - I selected 335i sedan manual transmission in virtual dyno. At least the torque projection should be pretty accurate.
Stock rods are forged, but a good idea to limit boost at low rpm to help them.
 

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Milan

Corporal
Dec 24, 2016
210
jebi se
As the owner of a C5Z and E90 (that's actually setup to turn) I can tell you right now the C5 is in a completely different league when it comes to handling compared to the E90.

Bang for the buck I don't know that you can have a better track car than a C5Z.
 
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