A Tale of Two Engines...Rod Failures

[Datka]

I agree. ESS SCs are proven to be reliable with s65 engines over a few years now.
Many use them without any issues including on the race tracks.
Something must have been installed incorrectly on that engine.
Sorry for your loss OP.

[Doc Oc]

Man that sucks to hear! Didn't you make a thread awhile back complaining about ESS' customer service because they wouldn't sell you a smaller pulley for their kit? If I remember right, the thread finished with you getting that pulley elsewhere. And you've gone through two engines sine then?

[MPACT]

No, that wasn't me. I didn't try to get the pulley through ESS at all and with all the other ESS cars out there, I find it hard to point to the SC. I had a boost gauge installed, did a dyno session to make sure boost and AF were solid. Did it put extra stress on the front main, yeah don't doubt that. Overboosted explosions usually look different. But at this point I am not sure what else it could be, something made two different engines go in the same manner.

[Doc Oc]

Oh sorry, got you confused with someone else who made a thread about ESS' refusal to sell them a pulley. He wanted it to compensate for altitude too which is why I asked. As someone who just lost an engine himself and has reservations about the new engine, I feel your pain.

[Sellout]

Originally Posted by Patrón

spinning the blower pulley is pretty easy, don't imagine it could cause that much stress unless the tension is extreme compared to stock.

Spinning a blower by hand is quite a bit different from spinning it with a real load on it. Full RPM and making boost, that blower is soaking up 70 horsepower easy.

But yeah, that's not what causes the #1 main bearing to go. It's the belt tension.

[Patrón]

Originally Posted by Sellout

Spinning a blower by hand is quite a bit different from spinning it with a real load on it. Full RPM and making boost, that blower is soaking up 70 horsepower easy.

But yeah, that's not what causes the #1 main bearing to go. It's the belt tension.

You're saying a supercharger takes 70% of the car's power?

[deansbimmer]

Originally Posted by Patrón

You're saying a supercharger takes 70% of the car's power?

It doesn't take 70% of what the supercharged engine is producing, but it's definitely not like throwing an extra alternator in there like you may think. It takes serious power to spin a blower to compress enough air to create 6+ psi in the intake tract of a motor spinning at 8k rpm. Why do you think they cog SC belts, add extra ribs, increase belt tension, or design high traction pullies to reduce belt slip?

[Patrón]

Originally Posted by deansbimmer

It doesn't take 70% of what the supercharged engine is producing, but it's definitely not like throwing an extra alternator in there like you may think. It takes serious power to spin a blower to compress enough air to create 6+ psi in the intake tract of a motor spinning at 8k rpm. Why do you think they cog SC belts, add extra ribs, increase belt tension, or design high traction pullies to reduce belt slip?

I guess the boost pressure would put a ton of resistance. Something I didn't think about. It's no wonder most cars are going the turbo route

[pbonsalb]

Centrifugal probably takes 5-10% of rwhp to spin, depending on how hard blower is being pushed.

[Sellout]

http://fepower.net/Dyno%20Results/dyno_results_14.html

http://www.yellowbullet.com/forum/sh...7&postcount=14

It's been tested quite a few times with different superchargers on different engines. They ALWAYS eat a lot more horsepower than you would expect.

This is the biggest reason that turbos always make so much more rwhp and rwtq with seemingly similar airflow numbers.

[aus]

Originally Posted by Sellout

http://fepower.net/Dyno%20Results/dyno_results_14.html

http://www.yellowbullet.com/forum/sh...7&postcount=14

It's been tested quite a few times with different superchargers on different engines. They ALWAYS eat a lot more horsepower than you would expect.

This is the biggest reason that turbos always make so much more rwhp and rwtq with seemingly similar airflow numbers.

Am I reading that right?
130hp at 6,000 RPM???

[Sellout]

Originally Posted by aus

Am I reading that right?
130hp at 6,000 RPM???

Here's another one. http://www.dragzine.com/news/lose-po...-loss-testing/

These are BIG superchargers, but in the case of an M3, 70 horsepower to turn the blower doesn't sound like it's far off to me.

[L4ces]

Originally Posted by pbonsalb

Centrifugal probably takes 5-10% of rwhp to spin, depending on how hard blower is being pushed.

Some reviews report 20-25% loss.

[pbonsalb]

I dont think so for our motors and the boost run on it. I think its much less for a 7 psi Si Trim on an S65. I think 20-25% drivetrain loss is about right, versus 15% for an NA S65.

The 489CI motor and the other 1000 rwhp motor in the links above are not really good examples to use except for the point that blowers drag on the crank.

[squartus]

I had main bearing failure on mine as well, ESS 625 kit stock boost. Let go 29k after running the kit, smoked the block had to do a complete rebuild. Waiting for the new stroker/Low compression engine to come it and strapping the blower back on it.

[deansbimmer]

Originally Posted by squartus

I had main bearing failure on mine as well, ESS 625 kit stock boost. Let go 29k after running the kit, smoked the block had to do a complete rebuild. Waiting for the new stroker/Low compression engine to come it and strapping the blower back on it.

Seeing as the only main failures I have seen in person or online have been supercharged, I wish we could find out what the variable is that causes main failure.... Its strange that some will go for years and tens of thousands of miles with no issues and others like the OP will blow two blocks in a few thousand miles...

Over-tension of the belt perhaps?

[okusa]

Originally Posted by squartus

I had main bearing failure on mine as well, ESS 625 kit stock boost. Let go 29k after running the kit, smoked the block had to do a complete rebuild. Waiting for the new stroker/Low compression engine to come it and strapping the blower back on it.

in for updates after install!

[///M Power-Belgium]

Originally Posted by MPACT

Hello all. As you may have caught on my other thread, I had an engine fail 100mi after installing an ESS S/C on my 2011.75 M3 with 67k miles. Upon inspection, it was a failure of #1 and/or #5 rods. See pic below.

I replaced it with a 25k mi donor off of eBay. I had the WPC/ARP kit installed while I was doing the swap. Well now after 1200mi, my other engine has also failed. It was a catastrophic rod failure of #1 & #5.

As you can imagine it is extremely frustrating to lose 2! engines in under 2000 miles!!

At this point I am looking for help on what may be happening. I find it hard to believe that this is simply 2 random rod failures.

The first one I can chalk up to bad luck, but that doesn't explain why the same rods failed on the new engine with new bearings in such a short time.

The car had the stock ESS tune, with only a smaller pulley to correct for altitude. I see no signs of overboost or even a bad injector. Piston isn't burned or no valve strike.

Engine #1 popped while I was on the freeway at full throttle making a 10sec pass.

Engine #2 went during my first warm up lap at the race track after the first straightaway. I had only been on track for literally 5 min. I had driven it 1000+ miles on the street without any issues previous to that.

So, please any suggestions as to what may be happening would be greatly appreciated!!

Also, I am worried about reusing the block pictured below. As you can see there is some heat discoloration on the bottom tray around the main bearing and I am worried that the block may have been weakened. Anyone seen this?

The German ellekz had also 2 X bearing failure on both stock S65s , and is running now with his third S65 !

His bearing failure nr 1 => http://www.m3post.com/forums/showthread.php?t=1029385
His bearing failure nr 2 => http://www.m3post.com/forums/showthread.php?t=1080379

Here a video from his bearing failure nr 2 !

[Doc Oc]

Originally Posted by deansbimmer

Seeing as the only main failures I have seen in person or online have been supercharged, I wish we could find out what the variable is that causes main failure.... Its strange that some will go for years and tens of thousands of miles with no issues and others like the OP will blow two blocks in a few thousand miles...

Over-tension of the belt perhaps?

Do any of the pulleys for these supercharger kits have dampeners?

[whats77inaname]

Originally Posted by Doc Oc

Do any of the pulleys for these supercharger kits have dampeners?

No, they don't. Having recently had a smaller pulley back-milled and picking up bigger injectors so I can run more boost, I'm starting to have some 2nd thoughts. Instead of running more boost, I'm seriously considering just having my Procede tuned with 2 tunes, one on meth, one not, and running just the regular 650 pulley kit and tune.

http://www.m3post.com/forums/showthread.php?t=589573

[Patrón]

Originally Posted by deansbimmer

Seeing as the only main failures I have seen in person or online have been supercharged, I wish we could find out what the variable is that causes main failure.... Its strange that some will go for years and tens of thousands of miles with no issues and others like the OP will blow two blocks in a few thousand miles...

Over-tension of the belt perhaps?

I would imagine that the force involved to start distorting the main bairings/main pulley would just cause the small pulley on the blower to slip, don't you think that would be the weakest point? i know if it were ribbed it would be but the pulley is smooth as is the belt. just my thoughts. i know vettes and mustangs are boosting a lot more psi than 5-7.5psi on the similar vortechs.

[deansbimmer]

Originally Posted by Patrón

I would imagine that the force involved to start distorting the main bairings/main pulley would just cause the small pulley on the blower to slip, don't you think that would be the weakest point? i know if it were ribbed it would be but the pulley is smooth as is the belt. just my thoughts. i know vettes and mustangs are boosting a lot more psi than 5-7.5psi on the similar vortechs.

Maybe I'm not reading your post as you intended for it to read, but it seems you're not understanding of the system design. The pulleys are ribbed (ribs aren't the same as cogs). The back of the belt is smooth but that'st not the traction surface.

The supposed issue causing bearing damage isn't related to belt traction- it's the additional pressure put on the crankshaft by applying a SC load. It may be torsional, side load, or harmonics causing the damage- I don't know. The front of the crank wasn't designed to bear such a load and therefore doesn't have the support that the rear main does. You can't compare the issue to american engines which are designed differently with comparably shorter crank snouts. A blower load placed on their cranks is closer to the front main support, but they're also just flat out beefier. The accessory belt on the S65 is much further away from the main than those examples and is the likely reason for the accelerated wear when boosted.