Hey guys, I have a quick question I hope someone can answer for me...

I have a supercharged ls3 c6 that broke a piston soon after it was Dyno tuned on 8 pounds of boost.. I had a new 1500hp rated ls3 block built from texas speed with wiseco dished pistons, which dropped the compression ratio to around 9.5 to 1 as opposed to the original 10.7 to 1 it had when it was tuned. Had the heads cleaned up and they are bolted on, motor going in tonight.

Im curious how safe it is to run this thing for any extended period of time? Am i safe for a test start or should i have a preliminary tune done before we even fire it?? I am very excited to drive this thing, it blew up only a few hundred miles after i bought it. Please advise! Thank you

 

As long as it's a closed loop tune you'll be fine to drive around outside of boost. The factory O2 sensors will keep fueling close to where it needs to be when NOT at WOT. Keep an eye on fuel trims if you have any way to monitor them to make sure they aren't maxed out.

A cheapo $20 ELM327 interface + an app on a smart phone will let you see them in real time if you want to be able to do some very basic logging.

 

What was the reason for the messed up piston?

 

8lbs of boost on a LS3 should not have snapped a piston.

The reason that the pistol let loose was detonation instead, caused by a bad tune, and guessing that you where not running a meth kit to keep the boost pressure cool/ safety margin to keep the octane level high enough to prevent detonation problems to begin with.

Hell, with a meth kit, your safe on the stock motor up to 650HP with super charger. Without meth kit and a bad tune, all bets are off, and you can blow a motor with a few lbs of boost like you did instead.

 

Actually safe higher than 650 on a ls3. Which is why I was asking what was the cause for the broken piston. I would have to assume as well that it was the tune.

 

Your car was originally tuned with a higher 10.7 CR---Which means the timing was lowered quite a bit to eliminate detonation
Now that you have an even lower CR of 9.5---means that you probably will be able to ADD a couple * of timing------ making it safe with the original timing based on a 10.7 CR--- assuming your boost level remains the same---

I'm too curious as to the piston failure--Without seeing the rest of the pistons--
Excessive timing would show damage to ALL the pistons/rings----If there is damage to others or even melted plug tips or aluminum specs on the plugs then NO I would not run it before a re-tune

 

Yea my initial thought was bad tune, I probably made it about 200 miles freshly tuned out of the realistically 4 or 500 miles I put on it total. It was tuned by a very reputable shop up here though called synergy motorsports, so I just kinda gave the tuner the benefit of the doubt.



I know the car has been supercharged for around 8,000 miles, 49k on it total. The guys before me managed to blow the transmission, which leads me to believe it was driven pretty damn hard... i just kinda went with that as the cause.

Thought about meth injection...summit has a NX kit for $300... Just afraid of pump failure 😵😵

 

The cheapo NX kit isn't progressive and just has a switch that you have to enable somehow when you want it to spray. That def. would not be my first choice.

 

I agree.... You spent quite a bit of money on the new motor. If you are going to go methanol at least get a good kit. I have the alky kit. I like it and it's progressive. There are however more advanced kits out there. But don't cheap out on the methanol kit.

 

Well first of all I would like to thank all of you for your replies. After further research you're correct lol the NX is not the best option. After further research I see that alky is probably the way to go if budget is no issue however I am $40k deep into a car that I've barely driven, and have decided to go with the slightly cheaper AEM progressive kit for $420, as opposed to alky @ ~$650 and just upgrade to braided lines as this seems to be the main difference...

I told the tune guy to make it very modest, and somehow still blew my motor. Will also tell new tune guy to make it modest, and keep the methanol flowing as more of a safety feature than a dependancy. I dyno'd at 525rwhp before, and the 6l80E tranny is rated for about 470 if I remember right?? I just want to get to drive the f*#!'n thing a little before I break anything else lol. Probably won't even start it up until somebody can verify that my tune isn't way out of whack. If anybody knows any good tuners up here in nor cal, please feel free to tag them! Thanks again guys.

 

I'm very surprised everything didn't survive at 525rwhp. That really makes me think going to a new tuner was a good idea

I wish I was in Northern CA, but I am not.

If you have a way to read the tune I can take a look and see if I see any obvious bad ideas. You'd have to have a HP Tuners interface in order to do that

 

It's weird because synergy is supposed to be one of the best, I walk in and there's multiple ZR1's all torn apart... Maybe he had a few the night before or something or like I said the car may have just been abused by the previous owner. Either way my mechanic doing the swap has a bluepoint computer, I presume that will show anything we need to know and then some?

 

It may just have been abused somehow. Hard for anyone to say for sure.

If he doesn't have HP Tuners or EFI Live then he can't do much of anything tune wise. I saw a post on HPTuners's facebook page showing HP Tuners running on a snap on scanner.. whether that is what he's doing or not, I have no idea

(I assume by blue point you mean some kind of scanner from snap on)

 

I would get the engine running and call a tried and true tuner to fine tune it for you as far as meth injection straight meth is the one.

 

As a tuner we are always the 1st one to blame when you have catastrophic failures But most of the time it is rarely the tune---
There are so many other things that could have caused the broken piston----As I mentioned it would be very helpful to know if there was any detonation damage to any other pistons---You did say you were the 2nd owner and suspect t was driven hard--Who knows how well maintained it was----
It could be from lack of fuel flow
Poor lubrication
Over heating
failing or DISABLED knock sensors
Too much timing would show damage everywhere as would poor fuel flow
With 10.7 CR and 8 PSI boost at WOT the timing should be approx. 11-15*
Having your tune would help us see if the tune was pushed to far to the edge
Being from Northern Calif---Synergy does have a great reputation as LS modders and tuners

 

the way the piston is broken, it shows it is from detonation. As tblu said, since myself being a tuner, we are always the one to blame.

Options that could've created this catastrophe:
- Too much timing (Tuners fault)

- Air fuel too lean (Tuners fault if commanded too lean, customers fault if not looking at the AFR when giving it full throttle, BAP/Fuel pump/Injectors might have given out.

- Intake Air Temperature was too high, also causing detonation (Kind of tuners for not pulling enough timing as IATs go up, Kind of customers for driving around for 3-4hours then giving it full throttle run after run. [Respect her and she'll treat you like a queen, disrespect her and she'll end up eating you])

- Bad tank of fuel/Wrong Octane (Could still be tuners fault though, but customer should know what his car feels like and if anything is wrong).

- If Catalytic Converters are still installed, maybe blocked off and causing too much back pressure which would crack a piston.

I've been tuning for the Middle East for the past 10 years and I've managed to easily get away with 16* of timing with ambient temperatures reaching close to 120*F on 8psi with no problems. Hell I've been pushing LS3/L76/L99 cars with 10-11psi on stock internals and pump gas (no meth) for years.

 

And a message to the OP, with forged internals and such a low compression, if you don't have at least 14psi (if fuel system handles it), then you're not enjoying your car! lol

 

Well there's actually one huge detail I totally forgot about because all of this happened so long ago.. It started knocking a couple days before it blew, but only when it was cold. I remember hearing it echoing off the garage wall, the couple times I drove it I actually got out and listened for a second, but it would go away after running for a minute or two. It seemed too deep to be piston slap, I thought for sure when the motor went that it was a rod bearing, when we saw the broken piston the other night (almost a year later) I just wrote it off as that being the noise but pretty sure that wouldn't happen slowly... Right? Now I'm starting to wonder if BOTH happened. Won't know if the tune was bad until I get it re-tuned next Friday. Think I'll tow it there to be safe. In the meantime I'm gonna rip the block apart and see if I had a bad rod bearing too... Something doesn't seem right.

 

I'd love to get a peak at that tune, just for ***** and giggles

 

There is a lot of generalization in that post.
I lost piston 7 on my stock LS3 after about 12K boosted miles. The tune was done my Matt from ECS/FSP - so it was pretty standard affair and it had a meth kit on it.
Replaced the motor with an ERL 416 and had it tuned by PatG. If you've ever dealt with PatG - he's a straight shooter but personable. We talked about his C6 that had the exact same kit and stock LS3 ... Which just so happened lose piston 7. Pat mentioned how his showed no issues before it let go and it had a safe tune and meth.
There are just no guarantees with a boosted motor - especially a factory stock LS3. Sure, there are the banzai/lone wolves that make 700 - 800 or more on stock internals - but for how long? How much spirited driving are they doing with said cars?
Original poster - don't get caught up in the name of the Meth kit, especially for what you're looking to do with it. The AEM kit would have worked just fine on your car and 95% of the cars on this site. You wanted to have it add some octane to lower your A/F ratio while under boost - no need for progressive this/that doo-dads in order to accomplish that. I'd be willing to bet, 99% of those with Julio's kit have ever touched the dials inside the black box, LOL! Most are having them installed by someone other than themselves, tuned by someone other than themselves and singing the praises of it's superiority based on marketing literature.