Switching side pipes to under car exhaust?

[Tom Wells]

ZOERA-SC7XX,

Also would make for HOT floorboards.

Don't know where you got that opinion!

My Cobra's floor is always cool. There is approximately a square foot (maybe two square feet - it's been eight years) of thin aluminized fiberglass insulation placed above each muffler. Even on 90 degree days with much idling at stoplights, or in parades, there's no heat coming from the floor.

Tom

[Ant]

I have had some burns to the inside of my legs from sidepipes.

I dont know about the power of your cars but this car I am building there aint a show in hell with the Reynard chassis etc unless you put the exhaust down the transmission tunnel inside boiler lagging etc as I attemped with an eight into one design, I gave up and built a complete system stepped headers going into merge side pipe collectors, with stainless 3" inside diameter perforated tube rolled and welded myself plus to get it quiet for round town insert a length of 2" perf tube wrapped in stainless and glass sound deadening, very restrictive but reports that you can get down to 92db with a basic engine so my nascar engine should be under its requirement of 98db to get certified.

Undercar looks better as it shows the nice bodyline etc (I hate sidepipes) but with 675bhp I havent the room to even run a 3" diameter area oval tubes underneath and the worst problem is where to fit large capacity mufflers, sometimes wish I had built a GT40 as you can do anything with them behind the engine.

[mdross1]

Originally Posted by Ant

I have had some burns to the inside of my legs from sidepipes.

I dont know about the power of your cars but this car I am building there aint a show in hell with the Reynard chassis etc unless you put the exhaust down the transmission tunnel inside boiler lagging etc as I attemped with an eight into one design, I gave up and built a complete system stepped headers going into merge side pipe collectors, with stainless 3" inside diameter perforated tube rolled and welded myself plus to get it quiet for round town insert a length of 2" perf tube wrapped in stainless and glass sound deadening, very restrictive but reports that you can get down to 92db with a basic engine so my nascar engine should be under its requirement of 98db to get certified.

Undercar looks better as it shows the nice bodyline etc (I hate sidepipes) but with 675bhp I havent the room to even run a 3" diameter area oval tubes underneath and the worst problem is where to fit large capacity mufflers, sometimes wish I had built a GT40 as you can do anything with them behind the engine.

Took my 460ci powered car to Tubular Automotive in Mass and had racing headers built then sent them Jet Hot for ceramic coating.Stainless Specialties custom built the chambered mufflers,local muffler shop built the rest.Also had to use cable operated clutch to give the headers all the room they need.

[JeepSnake]

Unique Motorcars also will build a kit with undercar exhaust. The Weavers converted my FIA car from sidepipes to street-type exhaust about a year ago (I've always liked the look, and I wanted to protect my 2 year old daughter as well.). After a lot of research on mufflers (many thanks to the tech guys at Flowmaster), I used the Hushpower Series II Shorties (12 inch case). These are typically used as a resonator in conjunction with the longer (18 inch case) Hushpowers. However, they are perfect by themselves for a Cobra, due to their small size, heat insulating properties, and "just right" exhaust note.

Based on my horsepower levels (~325 at the flywheel - very conservative engine around these parts), I went with 2.25" pipes. The headers are silver ceramic coated to keep down heat in the engine compartment, but the pipes are flat black ceramic to help them "disappear" underneath the car. With the Hushpowers, I actually picked up a little ground clearance compared to the sidepipes that were on the car originally.

In short, I love my undercar exhaust! (And my daughter does too; she wants to ride in the Cobra everywhere now!)

Hope this helps!