I’m seeing several shops working on sound pipes but not seeing the heat problem being addressed. The stock muffler appears to be fully wrapped in heat shielding. I will want to see thorough track testing to know that under sustained high load cases nothing melts. Also need to ensure after stopping with everything hot that nothing melts with no airflow.

 

We're currently working on shorty headers and the current plan is to put mounting points on them for the factory heat shielding. We'll definitely test on track when we get to the muffler point to ensure there are no issues.

 

Another concern is low airflow situations such as someone stuck in stop and go traffic on a hot day, or someone letting the car idle for 10 minutes on a hot day.

 

These are nothing compared to having 5 pounds per minute of 2,000ºF gas flowing through the headers on a race track.

 

Our first system is about to be put to the test!! We will be sharing all results, good or bad because that is how I operate my business. R&D does not always work 100% the first time. We have been the leaders in Corvette Performance for over 15 years and now with this new C8 platform you will start to see some of these other smaller shops or even import/exotic shops trying to get on board but they are so green to the Corvette platform. We love competition so we are very much looking forward to see how well others can build on this platform like we do. You can check out more of our exhaust system in our thread. Sorry, I did not mean to high jack your thread.

 

As a casual driver I probably won't mess with anything other than a cat-back, but I'd remove the trunk if I had to in order to get 180-degree bundle of snakes headers in there. I really hope someone tries fabing that!

 

Thanks LGM and LMR for your replies! great to hear you're thinking about it and looking forward to pacing your development efforts.

 

Bad *** exhaust.

 

The wrap also increases velocity which is essential for scavenging. For a stock engine with cats, the aftermarket must copy the NPP part of the muffler for the full range of performance but you will tire from the noise at cruise. An exhaust system is science and not guesswork. Don't let the sound fool you into believing you have improved performance. GM engineers made sure both factors were addressed. It is tradition that the first thing Corvette owners change is the exhaust. It is a big business but technology has moved on since the 60s. Some states test for smog. If you are not an engine engineer conversant in CAD/CFD, you are hissing into the wind. You can lease these programs for nothing, there is no excuse. The chaos in the after market will bring about legislation like it is in Germany.

 

Have you seen much of an increase in transmission temps with this new setup??

 

GM engineers also engineered the heat soaking C7 Z06. You are correct from the improvement aspect, the factory performance exhaust manifolds flow better than anything they have ever produced but there is always room for improvement. I can't speak to the cat back because we haven't started development there yet but I can tell you that there is no way 76lbs is necessary.

 

I am curious why I don't hear much about ceramic coating when dealing with heat. I ran ceramic coated exhaust on a couple of cars and noticed that underhood temps were kept in check without any of the original heat shielding. Of course I understand that shields are used to prevent radiated heat from melting things that may be susceptible, But I never saw an issue on my cars. I had no shielding on my FRS headers to my single turbo setup that ran up in front of the engine and was in close proximity (about a 1/4") from the plastic belly pan at the front of the car and never saw any signs of the heat affecting that cheap plastic.

I guess what I want to ask is, why is this not a commonly used option for exhaust heat management in Corvettes? I know some exhaust manufacturers offer it as an option, but it would seem like something that makes sense to use over wraps and shields as it is part of the exhaust.

 

Air gap heat shield is more effective at heat mitigation than coating.

 

Heat is a very critical thought on the forefront of the design process. Keeping the largest area possible between heat-sensitive components. Fabspeed also are utilizing a very high-quality heat shielding on the sport cats and x-pipe. We are now getting into the testing stages today and tomorrow. So more data to come!

 

If I'm not mistaken, because the coating is on the outside of the pipes instead of the inside, the material retains a lot more heat and thermal expansion issues may play a role.
I see few companies putting much effort into heat shielding in the past. Maybe that has changed with time.
Then come the problems like alternators that die early.

 

I think one of the other questions to be asked, with some top knotch vendors on this thread, is if you are going to be able to incorporate the NPP for an upcharge assuming testing goes well of course? THAT seems to be the pink elephant in the room over the last several years with the vettes, camaros, etc. Once (whenever that may be-2021) my car gets in, this will be part of the first thing that I do.

 

I think THIS is an answer to your question Doc. We just released our Valvetronic today - retaining full valve functionality.

 

Corvette C8 heat and thermal management discussion. I hope the community finds this information enlightening.

The C8 corvette has thermal heat mitigation engineering in place from the factory as do virtually all manufacturers of mid-engine sports cars. My team at Fabspeed Motorsport measured and recorded stock heat readings using thermal targets throughout the chassis for the stock NPP C8 exhaust on the DYNO and let the C8 heat soak. We also recorded heat readings with all Fabspeed engineered variants of exhaust systems. So we recorded the following: stock C8 ceramic catalytic converters and NPP exhaust with welded on tips. Then we recorded HJS german sport cats with stock NPP exhaust, Fabspeed catbypass and lastly HJS cats/CB pipes with 2 versions of the Fabspeed Supersport and valvetronic maxflo exhaust. We recorded the data on the street and dyno where it gets really hot due to limited ground airflow.

The stock rear NPP muffler is heavy and bulky weighs 76# all in. The Fabspeed Supersport X pipe for the C8 saves -38 pounds 17.3 KG versus stock. The Fabspeed Supersport X pipe and valvetronic X pipe saves a lot of weight but more importantly reduces the giant MASS/ body at the rear of the car and under the truck.

The NPP exhaust is so very bulky that you cant get a hand in there and air-flow is essentially blocked. All Fabspeed systems are thermally wrapped better than stock OEM C8 and as a result there are NO heat issues to manage nor worry about.

For example, our maxflo Supersport X pipes are wrapped with 2400 degree silica matt and 321 stainless steel foil. This is a much better insulation thermal mitigation solution than GMs single wall stainless steel foil wrapp with no insulation on their down-tubes. GM simply has stainless foil on the downtubes and a box around the muffler since it hangs so low. The Fabspeed flexible bellows are 321 stainless steel interlocked double wall USA parts that also reduced radiant heat versus stock flex bellows in the thermal testing target areas.

Our engineering team did Before & after Dyno testing along with Thermal testing everywhere on the chassis. The Fabspeed systems are lighter and ran COOLER than the stock systems while adding sports car sound, power and taking a ton of weight out of the chassis which has a solid performance & handling benefit. The Fabspeed pipes are 321 stainless steel wrapped with 2400 degree silica fiber. Heat is NOT an issue with Fabspeed products under any circumstances as our systems ran COOLER than stock. So C8 owners dont have to worry. You can lose the Boat-Anchor hanging off the rear of the car...........just like we have done with Porsche air-cooled and water cooled cars for 20 years.

Fabspeed has designed sport cats with HJS Germany for all the Mclaren cars with defense quality thermal covers as Mclaren cars have 4 catalytic converters snaking through the engine bay with ZERO airflow. The new Vette has alot more air-flow but we did not take that for granted just as would not take any sports car for granted. Any corvette C8 owner can make more exotic gutsy sports car sound and power and ditch significant weight and get a faster more nimbler car from various options. The new vette is wonderful and will only get better & better as GM engineering grows the brand and launches ZO6 and other models.

We have now built and delivered over 5 systems using our www.Unisonltd.com mandrel bender, FLOW mach 3 waterjet, HAAS CNC mills, Miller welding, Bystronic press brake, and other CNC equipment.

If any of you want to cruise by Fabspeed Motorsport you are cordially invited to take a tour and see our, design, engineering, and manufacturing equipment. Stop by and be our guest.

stay safe and be happy out there.

Joe Fabiani
President
Fabspeed Motorsport

 

Heat management is certainly a consideration when doing any modifications to the C8.

 

If General Motorsports (or any tier 1 OEM manufacturer) insulates and wraps their C8 headers, C8 OEM catalytic converters and portions of their rear cat-back muffler then aftermarket manufacturers should follow their engineering.

At Fabspeed Motorsport we routinely see Mclaren, Lamborghini, Porsche, Ferrari and other cars with integrated OEM Thermal Management systems. Fabspeed engineering has had GM, Porsche, Ferrari engineering consultants and power-train engineers advise us to follow their thermal management systems. In most cases we follow what we observe and often actually design thermal management heat mitigation systems that work better than OEM systems. For example, Mclaren and Ferrari often will have stainless steel foil welded to catalytic converters and often its not insulated. Sometimes a thin sheet of insulation then rewrapped with a .003" sheet of stainless steel foil. Fabspeed can duplicate that process but we have discovered through testing that the Defense quality thermal Blankets and systems we designed close to 8 years ago for McLaren cars work significantly better that OEM foil insulation. The thermal blankets have 321 stainless steel wire inside, 1/2" amorphous silica matt then Rock-wool Kevlar exterior fabric and 321 stainless steel hardware. Sometimes when one is reusing Mclaren or other stainless steel foil heat shields its "lime playing with razor blades" and the bulkiness is annoying to reinstall on the engine. NVIH is not reduced that much by foil insulation too.

The Fabspeed Motorsport 2200 degrees 1204 Celsius direct contact heat coverings insulate so much better than OEM and also keep sub-sonic noise and resonance " in the pipes" for better sports car sound. We use the same thermal systems for Ferrari 355, 360, and 430 headers.

For the new C8 mid-engined car we selected the same thermal blankets we use for all Mclaren cars. The C8 demanded it and we did not pinch pennies on the C8. At Fabspeed our C8 HJS German OBD2 EURO 6 homologated catalytic converters are completely covered and insulated by the aforemantioned covers. This keeps the engine bay cooler under any and all conditions and actually makes the catalytic converter function better at scrubbing/ cleaning the exhaust. Heat and precious metals work great together.

For the catback exhaust we wrap the top sections with insulation and cover with foil. These monster HJS German 200 cell HD catalytic converters support 1200HP each so we really let the new C8 breathe easy with no tune required to stop P420/P430 codes.