lancelot1

In preparation for buying my 2015 z51 I started reading this forum about a month ago. What struck me is the willingness of a significant number of late model corvette owners to jeopardize their warranty to improve their vehicles performance. I my self am tempted to install headers but can't accept the risk. My question is how do those that do rationalize it?

rb185afm

I used to be in that boat. Your simply rolling the dice. And then many try to hide the mods and take in for warranty work anyways, which f's the rest.

FlatPlaneCrankDreams

If you want to keep your warranty you can do mods that are easily reversible or undetectable.

I believe Diablosport tuners doesn't leave any trace of tampering when reverted back to stock.

An x-pipe would mostly help the sound and maybe gains a couple ponies.

Ported intake manifold and throttle body would be a great gain.

A cold air intake is reversed in 15 minutes.

Then if you're really trying to get the most out , but trying to look stock then porting the exhaust manifold.

rrsperry

Or, they can actually afford a rebuilt Lt1 or 4, and don't care?

lakemg

I'm taking a risk with my header install, but I'm playing with it more from an angle that they are more likely to void my warranty for a tune (which I do not have) rather than for the headers themselves.

I opted for the Kooks long tubes with their green cat x-pipe and stock NPP mufflers. I went with the (more expensive) green cats because they are supposed to not throw a check engine light. So far, with about a 1,000 miles since the header install, I have not had a check engine light and am running the stock tune. Will I gain more power, if I tune it? Sure I will and I will likely do so once the warranty expires, but for now, I just wanted the improved exhaust note that the headers will gain me. The stock 460 HP is plenty for me, but the car was just too quiet for me even with the NPP exhaust. Now it is perfect for my liking...

jamesc1123

I had a 5th Gen Camaro that I started modding pretty quickly and here is my thought process: the LS3 engine was built on the very stable LS platform. The engines can take it, and since so much was known about the engines at that point, I could make things more robust while I was at it. Knowing the reputation of these engines, and having a little know how, I knew I could feel totally fine about throwing a new cam in with full bolt-ons and never look back. I am a Mech Eng., so I generally understand how it works and I'm not worried about toasting the engine by swapping the air intake, intake manifold, or headers. Just buy reputable parts. If something calls for tuning, find a reputable shop (or get the parts that don't require a tune). Other people have done any mod you're considering, look at what their results have been.

GM generally won't and mostly can't just say you're screwed if you put a CAI on and toast your motor or rear end without proof that your modification caused the problem (allowed too much crap in the intake...)

All that said, coming from that platform to this one, I'm holding off on the mods because any money spent there is money that's not going into track fees or track prep (and with the lighter weight and better trans gearing, the car is just as quick in a straight line as my Camaro with an extra ~70hp).

lakemg

Well said and same reason I was not worried about wringing every bit of horsepower out of mine after adding the headers. I came from a mildly modified Pontiac G8 GT that would run 12.20s in good DA. When my C7 was still totally stock, it FELT like it was a second quicker than my G8, so I'm plenty happy with the power.

FYREANT

I rationalize by being able to beat a new Z06..

NSC5

Different people have differing risk appetites for different sorts of risks. I keep vehicles stock while in warranty but I used to go on a lot of solo climbing and hiking adventures in the Colorado Rockies which many people could reasonably call crazy so I am not casting stones at anyone for modifying their new C7. The funds to buy my Z06 came from risk management consulting so I have spent a lot of time thinking about risk but another part of the risk equation which Fyreant demonstrates is the satisfaction derived from the risk, in this case the warranty murdering modification

If we all defined perfect logic and rationality in exactly the same way it would be a damned boring world.

ferraf

To void a warrenty the mods would have to prove they caused the fault. If you lower temps with Meth I don't see how that can be faulted to cause engine damage. Changing headers has no issue or fault for transmission or engine failures. the Z06 has a forged engine and even pushing HP into the 1,200 range keeps ALL the specs clean. There are federal laws making it hard for the car manufacture to back out of a warrant item.

Example of an issue -
In a Consumer Alert issued by the Federal Trade Commission (FTC), the agency confirmed that “The Magnuson-Moss Warranty Act makes it illegal for companies to void your warranty or deny coverage under the warranty simply because you used an aftermarket part.” The alert outlines key provisions in the law that provides protections to car owners. As defined by the FTC, an “aftermarket' part is a part made by a company other than the vehicle manufacturer or the original equipment manufacturer.”

“The FTC’s reference to aftermarket parts is equally applicable to specialty parts,” said Russ Deane, SEMA’s General Counsel. “Under the Magnuson-Moss Warranty Act, the warranty cannot be conditioned to a specific brand of parts, services or vehicle modifications unless those parts or services are provided free of charge.”

The alert notes that a consumer has the right to patronize independent retail stores and repair shops for parts and service without fear of voiding the new car warranty. The dealer/vehicle manufacturer has the right to deny a warranty repair but they must demonstrate that the aftermarket part caused the problem. The warranty remains in effect for all other covered parts.

The FTC alert may be downloaded using this link: http://www.ftc.gov/bcp/edu/pubs/cons...ts/alt192.shtm.

The alert was issued in response to an FTC complaint filed last August by the Automotive Aftermarket Industry Association (AAIA), Automotive Oil Change Association (AOCA) and the Tire Industry Association (TIA).

NSC5

SEMA is more than just a little driven by self-interest. The M-M act was intended to prevent manufacturers from forcing consumers to buy standard maintenance items like oil and air filters from the captive dealer network or using the captive dealer network for normal maintenance (such as oil changes) in order to keep the warranty intact. M-M was never intended to provide warranty protection for consumers who modify their cars to change the performance levels outside of the stock performance envelope and nobody is going to win a case against GM, Ford, FCA, etc. for warranty denial after power adding modifications. Language on the manufacturer websites and in the warranty manuals specifically denotes these will be denied and it is only common sense that they are allowed to do so. A manufacturer can offer a warranty because they have engineered the system to perform in a certain manner and once an owner makes changes the manufacturer has neither knowledge of or control over how that modification impacts the performance and durability of the entire powertrain.

From GM's standard warranty boilerplate:

The New Vehicle Limited Warranty does not cover damage caused as a result of the following:


Alteration, modification, or tampering to the vehicle, including, but not limited to the body, chassis, powertrain, driveline, software, or other components after final assembly by GM.

If you modify the powertrain and the infotainment system breaks then you will have warranty coverage. If you make any modification to either increase the maximum power output delivered or to increase power over stock in any part of the powertrain operating curve your warranty is at risk. Warranty costs are calculated based upon expected failures at design operating conditions and it isn't reasonable to expect a manufacturer to provide warranty coverage when an owner changes those operating conditions. SEMA would love for it and purchasers of specialty products from its members to get a free ride but that isn't going to happen and shouldn't.

panheaddan

I opted for the Kooks long tubes with their green cat x-pipe and stock NPP mufflers. I went with the (more expensive) green cats because they are supposed to not throw a check engine light. So far, with about a 1,000 miles since the header install, I have not had a check engine light and am running the stock tune. Will I gain more power, if I tune it? Sure I will and I will likely do so once the warranty expires, but for now, I just wanted the improved exhaust note that the headers will gain me. The stock 460 HP is plenty for me, but the car was just too quiet for me even with the NPP exhaust. Now it is perfect for my liking...[/QUOTE]

How did the headers improve the sound? Deeper, more rumble, or just louder?

lakemg

How did the headers improve the sound? Deeper, more rumble, or just louder?[/QUOTE]

The exhaust note is more crisp and cleaner sounding and definitely louder with more pops and cracks when decelerating. I don't feel that it has a deeper tone, but the deep tone is more pronounced due to it being louder. I love still having the functionality of the NPP mufflers to quiet things down if/when needed. Even in stealth mode it sounds good.

ferraf

For me the Kook's headers and cat converter I made deeper rumbling louder sound. The tune can alway be reset to factory "IF" you had a warretny issue. Very easy to do if ever needed.

Bill Dearborn

You hope. Tunes only work by changing parameters in a set of tables provided by the manufacturer. A tuner can change the parameters back to stock and resave them into the ECM/PCM. However, it would be very easy for GM's software engineers and coders to design the software so it detects changes made to the memory. They don't need to detect what the changes are but only that changes were made. In fact it would be more likely they have this ability than not having it since it makes it easier to manage the software and code levels even if tuners had no ability to get into the tables at all.

As for tuners or tuner software providers saying their modifications can't be detected if everything is set back to stock that is pure BS. They don't have access to the software modules that check that sort of thing. The people who actually know how to do the tuning have no clue on how to actually modify software. That is like expecting somebody who uses Microsoft Excel to enter data into a spreadsheet to be able to redesign the Excel software. Huge difference between the two.

Bill

ferraf

Bill, can't argue that but reasonable to say they're not going to data dump your car and put so much resources when the changes are WELL within specs. Tuners are using parameters all provided to them by Chevy.

If Chevy can spend so much time detecting modifiable tables have been edited with-in spec's then every snag in the heat soaking, and A8 issues should be no problem for them to fix. Fact is the factory tune is horrible. Small rather safe adjustments make the car into what you thought you bought.

JMHO:

davepl

This is totally untrue. The current ECM keeps a history of at least the last 10 CVNs (Calibration Validation Numbers) showing whether or not each of those last 10 calibrations was official GM or not.

GM cannot and will not replace an engine assembly without a screenshot of that history showing it clean. This is official GM policy, documented numerous times on this forum.

You can't just "flash it back".

I "violated" my warranty for tire size. I would try to make the argument that this is a non-powertrain change but it'd be a long uphill battle against deep pockets.

They are REQUIRED to do this digging before replacing a motor assembly, short block, or other major engine component. Doesn't matter if you change only one number by 1%, the hash is totally different.

ferraf

Thanks, makes sense. I made the changes being told differently and see how much misinformation is out there. Even with this information I would do it again to get the car I actually thought I was buying.

BlackMoon

Does the Diablosport do anything notable? I know on other GM models they aren't ever mentioned. Looking for something and still keep my warranty. Thanks.

ferraf

I had the Diablosport tune to me Z06 a year before I upgraded and hand tuned. The DS tune is peppy and not bad at all. That said a hand tune with a few more upgrades does a huge difference. New AfE air intake and a hand tune not a bad place to start!