I was wondering if an oval tube would flow just as well as a round tube when exhaust gas it concerned. I have an idea for an exhaust but refuse to lose any ground clearance.

 

An oval tube won't flow as well as a round tube of the same area, but it will probably be close.

 

I dont think thats true, if it has the same amount of area inside, I dont see why it wouldn't flow just as good.

 

Because it has more perimeter than the round pipe for the same area.

 

It won't flow as well as a round pipe for the same reason press bent exhaust pipes don't flow as well as mandrel bend pipes.

 

Not quite, in that case there's a change in area.

 

Exactly.

 

Yes... close enough.

No. Not really. Not even close actually.

Laminar flow, drag and a few other things is the answer. Laminar flow is really the simple answer anyway.
Press bent pipe has an overall reduction in the flow area while oval tubing has more surface area in the flow path slowing the gas down. On a plus it does disrupt the reflected waves a bit from the exit of the exhaust.

 

So a oval pipe will cause more restriction than a round pipe? So if I were to run a dual 2.5" exhaust system it would actually flow like a dual 2 1/4 system? How much ground clearence do you save with a oval pipe? How hard is it to make the transition from round to oval?

I want to run a dual exhaust on my car. dump out in front of the rear wheels but save som ground clearence. I am just trying to figure a few things out.

 

Tucking round pipe down parallel to the driveshaft is probably your best bet and you won't sacrifice ground clearance.

 

check out spintech exhaust if you want to go oval, it is more expensive, but works well, they make a transition piece, along with mufflers made for the oval tubing. Same style as used by nascar, so it can't be that much of a power restriction, also, they give a conversion, to get oval pipe with equal flow area as round tubing.

 

thanks for the info, do you know the website for spintech?

 

http://www.drgas.com
http://www.spintechmufflers.com

 

Those 2 web sites will have all the info you would ever need to know about oval. I spend a lot of time there. I am in the proccess of designing an exhaust that will swirve and weav its way from my 2210s to some side dumbs all oval. I hear that the spintech mufflers don't flow the best, but "egh" my motor is going to push around 500 HP and it is a street car so whatever I am all set with a bit of loss in flow for ground clearance. The trick to keep the cost down is to remember that for small degree bends just cut the pipe and re-weld at a slight angle.

I plan on getting:
-2 oval mufflers
-2 round to oval tansitions
-2 40" oval lengths
-2 45 or 90 degree bends in case I need to really do a big bend.
-and maybe 2 oval turndowns. (all in 4"oval or 3.5")

Gonna cost a lot but I think well worth it.

I alsi think that this route of pipe being thinner and being able to wedge itself into spots will be worth the extra $

 

post some pics. I would like to run duals. I just want to see what it will look like. I think the spintechs are nice but I have not heard any yet.

 

try the website, or drgas site.