RICHARDJKNOX
CCCUK Member
Due to the warranty implications I probably wouldn’t do it .. but is anyone offering it ?
Just Curious C8 OPF delete
- Thread starter RICHARDJKNOX
- Start date
Chevrolet
CCCUK Member
Can get a "kit" to do it in Germany:
slystyle.de
SlyStyle OPF Delete Kit – Corvette C8 & C8 Z06 (EU‑Modelle)
SlyStyle OPF Delete Kit – Corvette C8 & C8 Z06 (EU‑Modelle) Maximale Performance & kompromissloser Sound Unser speziell entwickeltes OPF Delete Kit ersetzt die serienmäßigen Ottopartikelfilter (OPF) der Corvette C8 und C8 Z06 EU-Version durch hochwertige Edelstahlrohre – mit OEM-Effekt, aber...
slystyle.de
Chevrolet
CCCUK Member
If you click on/open the link above, at the top right it gives you the option to "Translate into English." No "Translate into American" option however. German car with the "delete"
OPF-Ersatzrohre - CN Racing GmbH - Camaro-Tuning - C8-Tuning
In unsere OPF-Ersatzrohre (Otto-Partikelfilter) wurde, im gegensatz zu anderen Eratzrohren der größtmöglicher Schalldämpfer integriert.
www.cobra-cn.de
Last edited:
RICHARDJKNOX
CCCUK Member
Thanks .. if someone in the UK could do it .. then maybe ..
Geiger Performance
New user
Hey everyone,
we are currently working on an OPF delete solution. The pipes will be thermo insulated and, as far as we know, they are the only OPF pipes on the market that come with brackets allowing you to re-install the original rear silencer heat shield.
Removing the OPF will trigger fault codes in the ECU. We can disable these via a software calibration, however we are also developing a plug-and-play emulator module that prevents the fault codes from appearing. The emulator will also be the more convenient option for customers located in the UK.
I should have the first prototypes ready in a few weeks and will be testing them on our C8 and Z06.
We’ll also be running the setups on our dyno to validate performance, as we are expecting some gains due to reduced backpressure. If there’s interest, I will share updates, photos, dyno results, and sound clips once testing begins.
we are currently working on an OPF delete solution. The pipes will be thermo insulated and, as far as we know, they are the only OPF pipes on the market that come with brackets allowing you to re-install the original rear silencer heat shield.
Removing the OPF will trigger fault codes in the ECU. We can disable these via a software calibration, however we are also developing a plug-and-play emulator module that prevents the fault codes from appearing. The emulator will also be the more convenient option for customers located in the UK.
I should have the first prototypes ready in a few weeks and will be testing them on our C8 and Z06.
We’ll also be running the setups on our dyno to validate performance, as we are expecting some gains due to reduced backpressure. If there’s interest, I will share updates, photos, dyno results, and sound clips once testing begins.
Attachments
Chevrolet
CCCUK Member
Wow! Thanks guys. That's a first! The famous Geiger cars, in beautiful Munich Germany, putting a post on here! I'll put this thread on the C8 Owners UK Facebook page where most of the UK owners are/chatting.
C8 Corvette owners UK | Facebook
www.facebook.com
RICHARDJKNOX
CCCUK Member
One question that hast to be asked is.. if the opf's were deleted, would the car fail it's MOT on emissions? Or even on visual inspection..?
RICHARDJKNOX
CCCUK Member
Fair play I think best leave it all alone
. Cheers
. Cheers
teamzr1
Supporting vendor
Owners of 2020–2025 Corvettes may install an aftermarket exhaust system on their vehicle in an effort to change the performance characteristics or look of the system.
However, a number of exhaust-related DTCs may set due to an aftermarket system
resulting in drivability concerns and calls to the Technical Assistance Center (TAC) with questions about the proper operation of the system.
When diagnosing the exhaust system on the C8 Corvette,
begin by checking if the system has been modified with any aftermarket equipment.
OEM System
The Original Equipment Manufacturer (OEM) exhaust system on the Corvette Stingray is designed to meet performance specifications and deliver specific exhaust tuning. The OEM system is available with polished or black-colored exhaust tips.
It also has a matte-black-colored heat shield around the body of the muffler.
GM Accessory System
The GM Accessory exhaust system for the Corvette is manufactured by Borla.
It is offered with exhaust tips that are polished stainless steel, black Physical Vapor Deposition (PVD) coating or carbon fiber.
The GM Accessory kit can be identified by the slightly golden-colored tint of the heat shield.
If the GM Accessory original box is not available as proof of installation,
ask the customer to provide the invoice or receipt with the part number clearly visible.
If there are any conditions related to the GM Accessory system, contact Borla for technical assistance.
Other Systems
GM does not support any other aftermarket exhaust systems for the Corvette.
Other than the GM Accessory Borla system, all other kits are considered aftermarket systems and
GM will not cover any diagnosis/repairs or parts/labor costs associated with the exhaust system.
To address any conditions that may be related to the exhaust system, the customer has the option to have the dealership return the exhaust system to the original stock system, return the vehicle to the company that installed the aftermarket system, or have the GM Accessory Borla system installed on the vehicle.
These are customer-paid options.
If there are any questions about the exhaust system, it’s recommended to create a TAC case and attach quality photographs of the system.
Refer to Bulletin #23-NA-103 for instructions on submitting photos to TAC.
Any problems in how engine is functioning, and 3rd party exhaust has been installed, voids GM warranty and vehicle owner
will be fully charged for all repairs and service time
However, a number of exhaust-related DTCs may set due to an aftermarket system
resulting in drivability concerns and calls to the Technical Assistance Center (TAC) with questions about the proper operation of the system.
When diagnosing the exhaust system on the C8 Corvette,
begin by checking if the system has been modified with any aftermarket equipment.
OEM System
The Original Equipment Manufacturer (OEM) exhaust system on the Corvette Stingray is designed to meet performance specifications and deliver specific exhaust tuning. The OEM system is available with polished or black-colored exhaust tips.
It also has a matte-black-colored heat shield around the body of the muffler.
GM Accessory System
The GM Accessory exhaust system for the Corvette is manufactured by Borla.
It is offered with exhaust tips that are polished stainless steel, black Physical Vapor Deposition (PVD) coating or carbon fiber.
The GM Accessory kit can be identified by the slightly golden-colored tint of the heat shield.
If the GM Accessory original box is not available as proof of installation,
ask the customer to provide the invoice or receipt with the part number clearly visible.
If there are any conditions related to the GM Accessory system, contact Borla for technical assistance.
Other Systems
GM does not support any other aftermarket exhaust systems for the Corvette.
Other than the GM Accessory Borla system, all other kits are considered aftermarket systems and
GM will not cover any diagnosis/repairs or parts/labor costs associated with the exhaust system.
To address any conditions that may be related to the exhaust system, the customer has the option to have the dealership return the exhaust system to the original stock system, return the vehicle to the company that installed the aftermarket system, or have the GM Accessory Borla system installed on the vehicle.
These are customer-paid options.
If there are any questions about the exhaust system, it’s recommended to create a TAC case and attach quality photographs of the system.
Refer to Bulletin #23-NA-103 for instructions on submitting photos to TAC.
Any problems in how engine is functioning, and 3rd party exhaust has been installed, voids GM warranty and vehicle owner
will be fully charged for all repairs and service time
RICHARDJKNOX
CCCUK Member
Amazing info thanks..
Geiger Performance
New user
Removing the OPF filters will trigger the MIL and fault codes. Over the weekend I installed our first prototype for initial testing, and I’m planning to do some dyno runs next weekend.
So far, I can say the sound is noticeably louder and more aggressive. The modification is not visible from the outside, as the original heat shields remain in place.
We’re currently working on a plug-and-play OPF emulator module. No ECU software changes will be required, and it’s designed to prevent fault codes and MIL warnings.
We’ve also tested the first prototype of our exhaust system and are now fine-tuning a few details. The system is designed not to trigger any fault codes. The C8 Corvette is quite sensitive when it comes to exhaust valve control, so this has been a major focus during development.
So far, I can say the sound is noticeably louder and more aggressive. The modification is not visible from the outside, as the original heat shields remain in place.
We’re currently working on a plug-and-play OPF emulator module. No ECU software changes will be required, and it’s designed to prevent fault codes and MIL warnings.
We’ve also tested the first prototype of our exhaust system and are now fine-tuning a few details. The system is designed not to trigger any fault codes. The C8 Corvette is quite sensitive when it comes to exhaust valve control, so this has been a major focus during development.
Attachments
teamzr1
Supporting vendor
GM complies with the EPA/SAE and does engine dyno testing with someone of SAE present so the HP & Tq numbers
GM uses are valid, and those numbers are at the flywheel, which means the difference at rear-wheel are within the margin of error
Non-American Stingray with a gasoline particulate filter,
-------------------------------------------------------------------- 475 HP @ 452 lb-ft Tq
American C8 Stingray is at
-------------------------------------------------------------------- 490 HP @ 465 ft/lb Tq
Difference at flywheel for Europe Stingray = 15 HP and 13 ft/lb Tq less than American Stingray
So the answer still is, is it worth the high costs to mod the exhaust for a few HP & Tq numbers and that would only be seen at max engine loads, seldom seen on the street driving, plus all the issues with GM warranty or smog testing ?
Do not forget for whatever reason the GPFs has to be installed again,
the cost and if you kept all the stock parts and filter
GM uses are valid, and those numbers are at the flywheel, which means the difference at rear-wheel are within the margin of error
Non-American Stingray with a gasoline particulate filter,
-------------------------------------------------------------------- 475 HP @ 452 lb-ft Tq
American C8 Stingray is at
-------------------------------------------------------------------- 490 HP @ 465 ft/lb Tq
Difference at flywheel for Europe Stingray = 15 HP and 13 ft/lb Tq less than American Stingray
So the answer still is, is it worth the high costs to mod the exhaust for a few HP & Tq numbers and that would only be seen at max engine loads, seldom seen on the street driving, plus all the issues with GM warranty or smog testing ?
Do not forget for whatever reason the GPFs has to be installed again,
the cost and if you kept all the stock parts and filter
RICHARDJKNOX
CCCUK Member
I think you are correct.. Lot of hassle for small gain so really not worth it.
One question though I notice replacement headers seem to offer a 25bhp gain.. Would Replacement headers fit the stock uk exhaust? Thanks
One question though I notice replacement headers seem to offer a 25bhp gain.. Would Replacement headers fit the stock uk exhaust? Thanks
teamzr1
Supporting vendor
If you think about this
Claims of Brake HP, that is an engine on an engine dyno with nothing attached to it to put load on the engine and no exhaust
Those numbers are bogus in the real world and are bloated numbers
Add the fact that is HPTq at the flywheel and the drivetrain to the rear wheels would reduce the numbers between 12 and 20% so
that 30 Bhp, at the rear wheels, would be even less of a gain
C8 with a rear engine means the exhaust pipe is only like 2 feet long, versus the exhaust length of a front mounted engine
thus rear design already has little back pressure
IF GM could get any free gains by how the pipes are bent, well they already did it with the production C8s.
Most con artists selling $2,500 to $4,000 headers state to get gains must also install their CATs
which in the USA is illegal if they never passed federal testing and if caught installing them it is a $10,000 fine to the vehicle owner
and $100,000 fine to whoever installed them plus at least 6 months in jail
Law here states since CATs must have a 8-year SMOG warranty by the nameplate like GM that there is zero reason stock CATs were replaced with illegal ones
C8s already have headers
Claims of Brake HP, that is an engine on an engine dyno with nothing attached to it to put load on the engine and no exhaust
Those numbers are bogus in the real world and are bloated numbers
Add the fact that is HPTq at the flywheel and the drivetrain to the rear wheels would reduce the numbers between 12 and 20% so
that 30 Bhp, at the rear wheels, would be even less of a gain
C8 with a rear engine means the exhaust pipe is only like 2 feet long, versus the exhaust length of a front mounted engine
thus rear design already has little back pressure
IF GM could get any free gains by how the pipes are bent, well they already did it with the production C8s.
Most con artists selling $2,500 to $4,000 headers state to get gains must also install their CATs
which in the USA is illegal if they never passed federal testing and if caught installing them it is a $10,000 fine to the vehicle owner
and $100,000 fine to whoever installed them plus at least 6 months in jail
Law here states since CATs must have a 8-year SMOG warranty by the nameplate like GM that there is zero reason stock CATs were replaced with illegal ones
C8s already have headers
RICHARDJKNOX
CCCUK Member
Again great info.. So decision made I'll leave it all alone
. Cheers
. Cheers
Roscobbc
Moderator
MOT standards are being raised from January 2026. To help prevent 'Ghosting' of vehicles there will be a requirement for MOT stations to provide 'live' photographic identity of vehicles. Testing of emissions standards will also become more stringent coinciding with the emergence of Euro 7 requirements. The test exemption enjoying by classic car owners may be reversed. How this will effect car owners who have removed or modified OEM installed emissions equipment is open to conjecture.