Dynamometer Results & Comparisons - My 5th Piston Gets Broken (dyno pics inside)

Hi guys,
This is some information about my car C6 2005 A4 full bolt-ons with stock engine not opened before or during the project. No issue for the last two and half years.
Car mileage before starting the project 65,625

Note:The date format in this thread is dd/mm/yyyy = day/month/year
Project Info:
Start Date:5\11\2011
End Date:5\3\2012
Project duration: 122 days = 4 months and 1 day :(
expected RWHP 480 - 520

Project mods:
e-force part#1594(3.5 pulley) with z06 fuel pump
http://i1085.photobucket.com/albums/j421/dfd9111/E111594.jpg

b & m trans cooler
http://i1085.photobucket.com/albums/j421/dfd9111/IMG-20111024-WA0007.jpg

mt 305 35 tires
http://i1085.photobucket.com/albums/j421/dfd9111/IMG-20111026-WA0000.jpg

innovate afr kit, boost and fuel pressure gauges
http://i1085.photobucket.com/albums/j421/dfd9111/IMG-20111024-WA0008.jpg
http://i1085.photobucket.com/albums/j421/dfd9111/3a439cafb4279fdf2b2a468b4037f099image200x200.jpg
http://i1085.photobucket.com/albums/j421/dfd9111/fuel.jpg
http://i1085.photobucket.com/albums/j421/dfd9111/holder.jpg

Dewitts radiator
http://i1085.photobucket.com/albums/j421/dfd9111/IMG-20111121-WA0008.jpg

This is my last three dyno runs pics:
First run (click on the picture to enlarge)
http://i1085.photobucket.com/albums/j421/dfd9111/2012-03-05203526.jpg

Second Run
http://i1085.photobucket.com/albums/j421/dfd9111/2012-03-05204155.jpg

Third Run
http://i1085.photobucket.com/albums/j421/dfd9111/2012-03-05204748.jpg

After the third run the tuner make tune more safer without additional dyno run or street test.

Next day 6\3\2012 I was happy to try my first street full throttle with new mods. I went full throttle (1st gear) directly my 5th piston gets broken as shown below:

http://i1085.photobucket.com/albums/j421/dfd9111/IMG_1749.jpg
http://i1085.photobucket.com/albums/j421/dfd9111/IMG_1748.jpg
http://i1085.photobucket.com/albums/j421/dfd9111/IMG_1747.jpg

What do you think the causes of my engine failure ????? :(

3.5 pulley im guessing is 3-4psi?

How much boost? Timming @ WOT? Max RPM's? Id also check the spray pattern on the injector from that cyl just incase.In 1st graph AFR is dangerously lean, better in 3rd but Id shoot for 11.3-11.5 to be safe-errr... Damn, that sucks...

That one graph shows it was 14.15 afr at 6000rpm, super lean under boost, the hp drops off as the afr goes lean on the graph.

Tell your tuner he sucks and ask him to rebuild your engine haha

What do you think the causes of my engine failure ?????

Shitty tune basically.

I'm really sorry for you brother, after all the efforts and time you ended up with this.

I'm absolutely sure that it was the tuner fault.

Wish you all the best.

Were you there listening during the dyno runs?

My guess would be during a couple of those runs you may have heard a pop thru the exhaust.

:(

Sorry guys I'm not familiar with tuning staff.
the feedback I received from the tuner "my car was safe but the RWTQ was too high for a stock engine which might cause this failure. I was not sure by his answer. So I post here to get inputs form experience tuners/car builders in this forum.

Thanks to all of you for your concern and inputs.

Were you there listening during the dyno runs?

My guess would be during a couple of those runs you may have heard a pop thru the exhaust.

:(

Yes, I were there. But the exhaust sound (corsa sport) was too loud I couldn't here any thing i was closing my ears.

Sorry guys I'm not familiar with tuning staff.
the feedback I received from the tuner "my car was safe but the RWTQ was too high for a stock engine which might cause this failure. I was not sure by his answer. So I post here to get inputs form experience tuners/car builders in this forum.

Thanks to all of you for your concern and inputs.

http://i1085.photobucket.com/albums/j421/dfd9111/2012-03-05204155.jpg

I'm the LAST one to blame a tuner. But. Either you had a tune issue, fuel issue or the wideband came out the exhaust stream. At around 5500rpm you can see it severely lean out.

http://i1085.photobucket.com/albums/j421/dfd9111/2012-03-05204155.jpg

I'm the LAST one to blame a tuner. But. Either you had a tune issue, fuel issue or the wideband came out the exhaust stream. At around 5500rpm you can see it severely lean out.

Brother I'm a customer. I paid for all new mods + labor and that's what I got. No one take the responsibility of that failure. Just I'm seeking for a decent answer form experts guys like you or others.

This is what happened. When the top of the piston breaks off like this, is becuse it got too hot. When that happens the ring gap closes up and stickes in the cylinder bore,breaking off the top of the piston,where it is beeing pinched. You more than likely have a broken block with a crack in the cylinder. The only way to prevent this from happening is to disassemble the motor with the pistons out and file the rings end gap bigger so that it has more clearance.

This is what happened. When the top of the piston breaks off like this, is becuse it got too hot. When that happens the ring gap closes up and stickes in the cylinder bore,breaking off the top of the piston,where it is beeing pinched. You more than likely have a broken block with a crack in the cylinder. The only way to prevent this from happening is to disassemble the motor with the pistons out and file the rings end gap bigger so that it has more clearance.


Maybe you should read the rest of the thread?

3.5 pulley im guessing is 3-4psi?

5-7 psi

That is a real clean break. Looks like it got weakened when it was NA and the boost just finished it.

The edelbrock kit is well known to have a real shitty fuel delivery through the rails. They should be modified with a dual feed to keep certain cylinders from running lean -ie-#5.

The runs above look lean but I have no idea what the timing is and the maggie style blower can be run leaner. The last graph looked alot better.

I would suggest to beaf up the fuel system and do some forged pistons. Maybe add a methenol system too.

Very sorry about this bro..

LS2 engines are very strong it will not break easily 1st , 2nd dyno runs were extremely lean (if the sensor didnt fell from the exhaust) 3rd run was alittle better but still mid 12s A/F ratio after 6400rpm with our crappy fuel and hot weather I recommend 11:1 - 11:5 A/F.

What size injectors did you run? why did it take 4 months for a very simple setup?

Good luck man I think it's time for forged setup, fuel system and more boost BUT WITH better tuner..

Very sorry about this bro..

LS2 engines are very strong it will not break easily 1st , 2nd dyno runs were extremely lean (if the sensor didnt fell from the exhaust) 3rd run was alittle better but still mid 12s A/F ratio after 6400rpm with our crappy fuel and hot weather I recommend 11:1 - 11:5 A/F.

What size injectors did you run?
Fuel Injectors (52 lb/hr)

why did it take 4 months for a very simple setup?
Simply no commitment.

Good luck man I think it's time for forged setup, fuel system and more boost BUT WITH better tuner..

Hi Bro,
Check my answers in blue color.

Brother I'm a customer. I paid for all new mods + labor and that's what I got. No one take the responsibility of that failure. Just I'm seeking for a decent answer form experts guys like you or others.

I hear you. I've tuned A LOT of cars. I can tell you without doubt. Either fuel issue, tuner should have let out, or the tune up was the issue. You can see it in the powerband. Look at the air:fuel as it begins to lean out and look at the hp/tq.

Did u dyno the car before the supercharger?
Was there any problems before the install?

Shitty tuner. That pull should have stopped as soon as it went lean. Piston top is scorched, obv it got hot and was hurt.

Shitty tuner. That pull should have stopped as soon as it went lean. Piston top is scorched, obv it got hot and was hurt. quote for truth

Maggies run leaner than turbos, yes. But maggies run @ 14.1:1AFR hell NO! I dont push my maggie over 11.4Afr with water meth injection!

Dang! I hope you get some kind of reimbursement over this. Hopefully you didnt sign any kind of paperwork(waiver) prior to the dyno. Most likely you did if this "tuner" works out of that shop often. The shop would make him get the waiver signed. But hey...if you didnt sign anything then I would go after him for the motor he toasted! No doubt in my mind it was the tune that caused the piston to fail.

Good luck with the next build!

NE other data logs?? Fuel psi comes to mind.....

Wow thats crazy lean

That must have been one heck of a ping. Sorry to see the damage. Hopefully once it's back together it's even stronger than before.

Does this look familiar? http://ls1tech.com/forums/forced-induction/1547915-my-ls1-finally-dumped-me.html