[Oldfart]

I keep seeing posts in Corvette forums about head/valve train issues blowing engines in Z06 Corvettes, but I have not seen a single instance of a blown engine in a ZL1. As far as I know the engines are basically the same with the Camaro having better cooling. Am I missing something? I had just looked at a 2013 Z06 with 13,000 and it's on it's THIRD engine! First one ran hot and ate oil, second one dropped a valve and self destructed.

I realize any car can have issues, especially if you beat the snot out of it. I'm looking to get into something that I can keep a long time. Thanks for any input.

[soloknight6]

C6 corvettes use LSx engines. A 13 Z06 has an LS7 engine (naturally aspirated 427.), some were prone to problems.

LS engines are totally different though Old Fart, its a new generation of small blocks with the LTx engines in the current Camaros and Corvettes. Apples and Oranges sir.

I believe the LT4 is a great engine, its built as stout as they come to handle the ridiculous power from the factory. Longevity should be there in spades, even if you beat the car up. Just be sure to perform recommended maintenance, and DI engine maintenance. Like media blast the valve coking off around 100k miles.

Most high end euro DI cars recommend that service, we should perform it also with our new DI engines. I know I will.

[Oldfart]

Originally Posted by soloknight6

C6 corvettes use LSx engines. A 13 Z06 has an LS7 engine (naturally aspirated 427.), some were prone to problems.

LS engines are totally different though Old Fart, its a new generation of small blocks with the LTx engines in the current Camaros and Corvettes. Apples and Oranges sir.

I believe the LT4 is a great engine, its built as stout as they come. Longevity should be there, even if you beat the car up. Just be sure to perform recommended maintenance, and DI engine maintenance. Like media blast the valve coking off at 100k miles.

Most high end euro DI cars recommend that service, we should perform it also with our new DI engines. I know I will.

Thanks for the answer. This is what happens when you're old and have to have brain surgery to remove a tumor and your memory gets trashed. That's why it's time to treat myself to a nice car.

[DangerZL1]

When the C7 Z06 first came out there were a number of posts about engine failures. It was discouraging and would have made me think twice about buying one. Before I started looking at the ZL1, I was considering a C7 Z06. I haven’t seen many posts about C7 LT4 engine failures in a while. The only problem that would concern me is the on going A8 trans torque converter problems. The lack of the A10 and the DOD in the C7 are the two main reasons I’m leaning towards the ZL1. Of course, saving over $20k doesn’t hurt either.

[soloknight6]

Originally Posted by Oldfart

Thanks for the answer. This is what happens when you're old and have to have brain surgery to remove a tumor and your memory gets trashed. That's why it's time to treat myself to a nice car.

One hell of a car to treat yourself to! Enjoy it, and drive the snot out of it old timer!

[crunch527]

Yes, the LS7's have a valve design weakness...hollow titanium valve stems that are prone to drop/break when shifted at 7K+ rpms...just a poor design...as a general rule, every LS7 should have the valves and lifters replaced. Then the LS7 is bullet proof.

LT4 issues are the fact that when in an A8 (auto) ZO6 there isn't enough cooling capacity...engine compartment is too cramped, not enough airflow...not enough supplemental coolers/heat exchangers...the 17's got an update to the supercharger bricks but the A8s will still overheat on the track.

The LT4 in the ZL1 Camaro seems to be bullet proof in terms of reliability...no valve issues and no overheating.

I think there is a good possibility the next gen ZO6s will have the cooling issue sorted...

[Mr. Meh]

Wasn't this thread deleted. I'm sure I replied to this very one yesterday.

[Oldfart]

Originally Posted by Mr. Meh

Wasn't this thread deleted. I'm sure I replied to this very one yesterday.

It was, I posted it in the wrong forum by accident. It got pretty funny before it got deleted.

[Android42019]

Sadly I believe I’m the only one that’s had a problem so far.
Split the Camshaft and a rocker failed, that was at around 13.6k miles, since they replaced the cam and all 8 rockers it runs just like new maybe even just slightly better.

Service tech said nothing I did should have caused it so more than likely a bad part.
https://youtu.be/NQ1mPLHLuio

[PinHead]

Originally Posted by Oldfart

As far as I know the engines are basically the same with the Camaro having better cooling.

Hey O/F this is O/F #2,

I'll give you the Cliff Notes version before I forget, (as my short term memory is about as long in duration as one cup of coffee),

The new GM SBC (LT1/LT4) Blocks, now called a GEN 5 Block, are a huge improvement from the old LT1(350/350) of the past. LT1 are naturally aspirated and the LT4 is Supercharged. Both have forged piston/cranks and have aluminum blocks with aluminum heads. Most these engines are now assembled by CNC Machines and robotics where tolerances can be maintained and variances eliminated.

Tonawanda, NY GEN5 Engine Assembly Plant
https://youtu.be/bLtZNtvc1Aw

The engine is now capable of Variable Valve Timing where oil pressure can be used to clock the camshaft to deactivate cylinders to increase fuel economy and retard/advance timing via a Cam Phaser. I have no idea why GM included this in a high performance application.

The biggest improvement of the strength of the block is the extension and strengthening of block's bottom end, (its now a Y-Block-Think a MOPAR block), and now has 6-BOLT MAINS.

Each cylinder has a Oil Spray tube that bathes the cylinder walls with oil that increases cooling/lubrication.

The traditional SBC intake manifold is now gone as these engines use Direct Fuel Injection, (called DI) and uses a lifter oil manifold assembly.

The camshaft is a hydraulic roller lifter with a split overlap cam profile. They used a beefed up slider tip stamped steel rocker arm. Why they didn't use a full roller rocker arm is still puzzling.

It also runs a mechanical fuel pump off a gear on the camshaft, (which I don't like as it creates a parasitic HP load/loss).

The down fall that you'll have to get used to is that you can no longer swap you're old SDB parts and interchange them like most of us have done for years. On the flip side we can now have fun parts hunting and draining our wallets.

Here's a video from GM that explains it in depth.
https://youtu.be/g8kQoSfhHi0

Here's some other helpful articles;

How to ID a late model SBC
http://www.superchevy.com/news/ghtp-...1-small-block/

Chevy Block Casting Numbers Chart
http://www.enginelabs.com/news/refer...sting-numbers/

Happy hunting and, if you're like me, need to exercise the synapse as they're few and far in between these days.

Enjoy.

[TheRealJA105]

LT1 has cast pistons

[Inspector 17]

I think the biggest difference is the cooling additions on the ZL1. There don't seem to be nearly (if any) reports of overheating issues on the ZL1-based LT4 as there were on early Z06-based LT4s. As others have said, I think they made corrections to later model Z06s to help with that issue. Bottom line is running an engine too hot is never good and can definitely account for premature failures.

One thing I noticed personally is the oil consumption difference between the ZL1 and the Z06. I'll preface this with the statement that I've seen others on here and social media mention that they ZL1s burn some oil. I've not used a drop in mine. I've had it on the track and at autocross events. Closing in on 4,000 miles now and I've added no oil. My buddy has a Z06 (2014 or 2015 I think) and when we run side by side on the same track, he always has to add oil. He doesn't have any overheating issues, just some oil consumption. My best uneducated guess is that it has to due with the tolerances on the two engines varying slightly and the fact that he is running a different oil.

Bottom line is that I've never had an issue with mine. Buy away and enjoy!

[Stephen12ZL1]

this entire topic is flawed because of the fact someone didn’t know the difference between a C6 Z06 with an LS7 and a supercharged Z06 LT4...hmmm. So, as factory variables exist some seem to burn oil and some don’t. Is it the break in or driving style that causes this problem? I did an “in between” break in style with a few WOT sprints to rpms 1500 below redline. Was I right? I have no idea but the car was on track at VIR with 1550 miles and performed flawlessly with no oil consumption.

[PinHead]

Originally Posted by TheRealJA105

LT1 has cast pistons

You are correct. They're called cast hypereutectic aluminum pistons

That's what happens with long posts.

Thanks for the catch