Turbo-Geist

Back in August, I found these orange deposits on the #7 spark plug. I thought they were kind of odd so I asked a few questions and did some research online. Most of what I read seemed to indicate that they were from additives in gasoline. I thought it was strange they were only on one plug, but the car was still running very strong so I continued racing it. I put an electronic boost controller on the car in September, it went to the road course in October and I was getting ready for the track rental in November.


Unfortunately I made a mistake. Now, almost 2 months have passed, but I figured I would post up the details and pictures of the engine failure. I was racing late at night in early November and had just shifted into 5th gear. At around 160mph, it felt like the car was pulling timing and I saw a glowing orange spark shoot out to the side of the car before everything went silent. I quickly pushed in the clutch and put the transmission in neutral as smoke began billowing into the cockpit. I noticed that the tach was reading 0 rpm and almost every warning light was on. After coasting for a couple of miles and finding a safe place to park, the large puddle of oil under the car was a good indication that something was wrong.

A couple of days later I pulled this from the driver’s side of the block in the vicinity of the #5 cylinder skirt. This is a picture showing a 5.3L engine in the background for reference.


Now it was time to pull the engine and do further investigation.


Driver’s side


Passenger’s side


#5 piston as found after removing the heads


The piston tops and ring lands were still intact. Notice the orange deposits on the head gasket around the cylinder bore. Interesting that they are very similar in color to the deposits I found on the spark plug. I still run GM Dex Cool Coolant and it is the same orange color. I had a head gasket leak that gradually got worse and then let go at just the right moment. These were factory 86k mile gaskets and TTY head bolts. I’m impressed that they held up so well.



Oil Pan removed. #5 connecting rod is broken. Unfortunately, water is incompressible.

Turbo-Geist

I’ll get some more pictures up later, but I really don’t look at this failure as finding the limit of the stock rotating assembly and cylinder case. I suspected that the head gasket was compromised and made an error in judgment by deciding to go for one more race. I think with a set of LS9 gaskets and head studs, this engine would have lasted even longer at this power level.

robert miller

Hate it for you buddy, But do agree with you on the problem with it. Good luck putting her back together over the winter. Robert

MVP'S ZO6

Jesus H Christ!!

Nothing like testing the limits of stock components.

ajrothm

Not gonna buff out...

Sorry man..



Time to build a monster!

slow ride

That sucks. Whats next, small cube build or upgrade the turbos and run a larger engine, etc? We need someone to try the newer turbonetics 61mm billet wheels/b covers haha.

Turbo-Geist

What are the details on the Turbonetics 61mm snails?

I'm in the middle of deciding on the next combo. There are many different options. In some ways I would like to continue pushing a stock motor, but changing one of these engines out is a decent amount of work without a lift. I'm not sure if a stock engine and displacement is going to get me to my ultimate goal using a 6 speed. This is still very much a street car that likes to spend some time on the track. The night it broke is the first time it has ever been on a trailer.

I feel like the best thing is to build an engine and reuse the turbo kit for now and then do a custom kit later.

MawneeC5

Ouch! looks familiar to me

slow ride

The billet 61mm compressor wheels are the largest turbonetics billet wheels that will fit the b covers. Others have gone bigger but not with turbonetics. You could also do a 62-1 cast 62mm wheels like I have and upgrade to a f1-65mm exhaust wheel.

You will make better power with a smaller engine and the stock kit as it sits. Less backpressure, etc but a larger motor would make more torque. You could do a forged rod/piston stock engine for not much if you like to build engines and have a good machine shop you trust. Even a simple stock stroke ls2/ls3 block would be somewhat cheap except for the block. Time to see what you can scavenge from the carnage you have first though.

Chris Stewart

r.i.p. stock LS1

JDS99

Dang man, ... At least you got a lot of good life and times out of it. I think I see some deformation in the fire-ring on that cylinder, possibly where the leak was. Agree that was what killed it for sure.

Curious to see what you end up doing engine wise. If you're going to go custom kit down the road, i'm sure you'll spec the new engine appropriately.

So, what is the ultimate goal you refer to then?

Turbo-Geist

Can you elaborate more on this? I've heard different theories on it. I'm interested in looking at this only from the standpoint of using the TTiX kit and the T3/T4 hybrid turbos that are available to fit it. I'm also only looking at it from the standpoint of using a 6-speed manual transmission and mostly 93 octane and methanol injection.

It seems there have only been a few people make close to 1k rwhp with the 58/62 turbos and a 346 or 347 engine. They seem to be very happy in the 900 rwhp range. The 62/65s are capable of over 1k rwhp but there may be some issues between shifts with a low compression engines and spool.

With a 402 or 427, the 62/65s (0.82 A/R exhaust housing) seem to be very capable of 1100 rwhp or more. It seems that not to many people have explored the upper limit of this particular combination.

Yes, the fire ring was very deformed at the 9 o'clock position on cylinder #5. There is also evidence that the gasket was compromised at the 6 o'clock position on cylinders #3 and #5. The #3 rod is slightly deformed, so that cylinder may have filled with coolant also.

My goal this year was to run 9s with the stock internals plus a cam. I did that in the first half of the year and then ended up working continuous 12 hour days for most of the summer. I was planning to go for 9.50s before the end of the year until this happened.

The next goal is to run 8s with a TTiX kit and a 6 speed manual transmission. So far, I haven't found any limitations with the X kit. We'll see what happens.

jimbos'ss

Someone on here was having issues with boost control, but I think he's running bigger cubes. Good luck with the rebuild, i'm absolutely amazed by the destruction of your motor.

Pekka_Perkeles

Just kidding:

It's all in the tune. It's all in the tune. It's all in the tune.
It's all in the tune. It's all in the tune. It's all in the tune.
It's all in the tune. It's all in the tune. It's all in the tune.
It's all in the tune. It's all in the tune. It's all in the tune.
It's all in the tune. It's all in the tune. It's all in the tune.
It's all in the tune. It's all in the tune. It's all in the tune.

I doubt it's in the tune. OP may even have logs to and tune to post here if someone thinks it's the tune.

I will be interesting to see the rod bearings.

I would also like to see more details about head gaskets (and possible leak areas).

Pekka_Perkeles

That's not uncommon with enough boost and/or knock.. But it won't necessarily break other things, but it all depends.

Turbo-Geist

I'm having trouble following what you are trying to say. If you have a statement to make, go ahead and make it and we can discuss it right here.

Pekka_Perkeles

Sorry, english is not my default language. Please also forget the joking about the tune.

If I understand this right (which I may not) OP thinks that the failure is because of leaked coolant (because of head gasket or bolts).

If that is the case, I don't see the evidence or don't understand it. Head gaskets have leaked at 6 o'clock, yes, I agree. But other than that do you really think your rod/block failure at WOT (if I understand right) is because of leaking gasket.

For that reason it would be interesting to see the all the connecting rod bearings.

Turbo-Geist

Ok, thanks for clarifying. You are correct. I believe the main cause of failure to be that the head gasket began leaking a large amount of coolant into the cylinder and because liquid is mostly incompressible, it caused the rod to fail and proceeded to cause the rest of the damage to the block and piston. The plugs on this side of the engine were wet like they had been in water and weren't firing. The coolant smelled like gasoline and the next day when I drained the oil pan it it had a large amount of coolant in it. None of the pistons or spark plugs are showing any signs of detonation.

I still need to remove the rods, crank, and pistons, etc. from the engine and will take some pictures and post them up this week.

What kind of pictures would you like to see of the head gaskets?

I'm open to any ideas about what else may have happened, but this was a stock internal LS1 with 20 psi manifold pressure and the original stock head gaskets and bolts.

user_name

Probably just a terrible tuner. That's what I'm going with.

Turbo-Geist

I learned from some of the best. Lol.

It definitely wasn't those rod bolts that everyone says are weak on the LS1 and won't hold more than 500hp. The rod bolts are still doing their job. I'll probably reuse them in the next engine.