C3 Race Car Build

teamzr1

teamzr1

Supporting vendor
Primary pipes in the exhaust manifold should match the exhaust port diameter on the cylinder head; but to reduce reversion, a primary pipe that is slightly larger than the exhaust port is better.

Reversion is the flow of exhaust gasses back into the combustion chamber when the downward movement of the piston creates a vacuum in the cylinder.

The exhaust valves are still open when the intake stroke begins. This presents the potential for exhaust gasses to be drawn back into the combustion chamber when the piston moves down the cylinder.

Any exhaust gases that are drawn into the combustion chamber will displace the air/fuel mixture being drawn in through the intakes valves and will increase the temperature in the combustion chamber, thus reducing the volumetric efficiency of the engine, as well as engine power.

Preventing reversion will reduce the contamination of the air/fuel mixture by the spent exhaust gasses and will improve the efficiency of the engine.

An anti-reversion header or AR header that is specifically designed to inhibit reversion would be your best choice. Anti-reversion headers have a built-in lip that restricts exhaust gas flow back into the combustion chamber.
 
Oneball

Oneball

CCCUK Member
The primary pipes are a good match to the head ports and about the right size, 1 7/8” for a 355cui I think.
I’m not a fan of the collector size at 4”, I think that’s done for looks, if I was specing it I’d have gone for 3” or 2 3/4”. It’ll go down to that anyway but it means you’ve got an expansion chamber in essence at the collector point which is the wrong place as it’s loosing the effect of one cylinder on another.

Id like to keep a 2 3/4” or 3” system throughout.

Am going to the exhaust place tomorrow afternoon for a discussion.
 
teamzr1

teamzr1

Supporting vendor
Oneball, were you able to solve and get the sound level down ?

Wish I could recall back in the late 1970s I had found a way to get sound level down on the hooker headers I used in my 1975 C3

75C3dragsb.jpg
 
teamzr1

teamzr1

Supporting vendor
On the subject of exhaust sound levels, look at this crap :(

A new law in Oct 2021 passed in NY basically making any aftermarket exhausts which are not OEM as illegal and thereby subject to a fine of over $1000.

Any Shop who installs such parts may well lose their license

Legislation (S.784-B/A.471) Increases Penalties Against Motorists and Repair Shops that Illegally Modify Mufflers and Exhaust Systems to Make Them Excessively Noisy for Motor Vehicles and Motorcycles

Tramp Governor Kathy Hochul today signed legislation that increases penalties against motorists and repair shops that illegally modify mufflers and exhaust systems to make them excessively noisy, an act associated with aggressive driving that harms community health, safety and comfort. This bill amends vehicle and traffic law, increasing fines and penalties and creating stricter regulations on vehicle equipment.

Maximum fines for installing illegal equipment will be raised to $1,000, an $850 increase.
Inspection stations will also be required to inspect motorcycles to ensure mufflers and exhausts have not been illegally modified.

"Every New Yorker deserves to feel safe and comfortable in their community, ( Yet she demands gang bangers not be held or have to bay for bail)
and that includes cracking down on excessively noisy vehicles on our streets," Governor Hochul said. "This legislation deters drivers from installing illegal vehicle equipment that results in dangerous noise levels that can contribute to hearing loss and increased emissions."

With an increasing number of drivers making muffler and exhaust system modifications that increase noise and pollution levels, this legislation will protect both public health and the environment. This legislation not only creates a deterrent for
If repair shop owners willfully violate this legislation and install illegal vehicle equipment three times within 18 months, they risk losing their certificate of inspection stations and operating certificate. These measures will help prevent dangerous noise levels that can damage bystanders' hearing, as well as decrease harmful emissions being released.

Every New Yorker deserves to feel safe and comfortable in their community, and that includes cracking down on excessively noisy vehicles on our streets,

Senator Andrew Gounardes said, "Today, residents across the state can breathe a sigh of relief knowing that they won't be kept up at night by excessively loud mufflers and exhaust systems. This is a quality of life and public safety issue that plagues our community for no logical reason other than to simply make noise. Now that the SLEEP Act has been signed into law, we can remove these loud and polluting vehicles from our streets once and for all. I'm grateful to Governor Hochul for signing this bill so we can hold people accountable for their disruptive behavior."

Assemblymember William Magnarelli said, "Across New York, many communities and neighborhoods are being disturbed by motorists and motorcycle riders operating illegally loud vehicles, often late at night. This bill looks to crackdown on the problem by going after repair and installation shops that illegally modify car, truck and motorcycle exhaust systems. In addition, increasing the fines will act as a deterrent."

Councilman Justin Brannan said, "I want to thank Governor Hochul for signing this bill. My constituents have been demanding action ever since we saw -- and certainly heard -- drivers illegally modifying their mufflers and disturbing our quality of life and, quite frankly, scaring people! It is our hope this new law will bring some peace and quiet back to our neighborhoods in the night."

Bay Ridge Advocates Keeping Everyone Safe (BRAKES) Founder, Maureen Landers said, "Modified exhaust systems serve no purpose other than to create fear, chaos and intimidation. The SLEEP Act is a major step in reducing noise pollution and addressing the reckless driving that coexists with modified vehicles. Thank you, Governor Kathy Hochul and Senator Andrew Gounardes for doing their part to make our streets safer for all."

Yet the amount of crime in NY has jumped 400 percent in last 2 years and even told cops not to arrest those caught doing crime of any kind :(
 
CaptainK

CaptainK

CCCUK Member
teamzr1 said:
Bay Ridge Advocates Keeping Everyone Safe (BRAKES) Founder, Maureen Landers said, "Modified exhaust systems serve no purpose other than to create fear, chaos and intimidation........"
Click to expand...
This is the quote of the year for me. :ROFLMAO: :ROFLMAO: It must be fear and intimidation those people are experiencing that turn to look at my Vette a I drive by, compelling them to put on a fake smile and get their phones out to video the Vette to show to the Police and counsellors later when they are seeking support, whilst also giving the international hand signal for "rev it mate".

I actually find a (within reason) modified exhaust to be a safety thing - you can't exactly claim you didn't hear my Corvette coming along the road, thus you wouldn't accidentally walk out in front of it without knowing it was there (unless you are deaf etc). Whereas modern quiet cars, its quite easy to not realise they are there.
 
Roscobbc

Roscobbc

Moderator
What is it the biker say? ........"loud pipes save lives" - perhaps some of the car and bike guys need to figure-out what makes the members of Bay Ridge Advocates 'tick' and publish it for all to see.........some of them must have a few nasty perverted secrets to hide........
 
johng

johng

CCCUK Member
Thought you had dropped off the face of the earth Tim, good to see you haven't! What's your current plan for a first outing?
 
You must log in or register to reply here.
Top