Offroad-Express

Hey guys, just wondering since I have to change my exhaust how a 3" system would run on my 2l 3y?

Way too big 2 1/4 would be much better.

I plan to run 2.5" on my 3.8L V6

Just curious...how can an exhaust be too large please?

The answer is simple. Cold air is dense air, and dense air is heavy air. We don’t want our engine to be pushing a heavy mass of exhaust gas out of the tailpipe. An extremely large exhaust pipe will cause a slow exhaust flow, which will in turn give the gas plenty of time to cool off en route. Overlarge piping will also allow our exhaust pulses to achieve a higher level of entropy, which will take all of our header tuning and throw it out the window, as pulses will not have the same tendency to line up as they would in a smaller pipe. Coating the entire exhaust system with an insulative material, such as header wrap or a ceramic thermal barrier coating reduces this effect somewhat, but unless you have lots of cash burning a hole in your pocket, is probably not worth the expense on a street driven car.

Thanks for the advice everyone, 2" will do fine I think. Another quick question to any 1st gen surf gurus, is it legal to drive around with the back canopy off?

yes it is called a carson top and is legal to remove, youll notice that the rear belts are all lap belts etc.
However im not saying the cops arent going to pull you over and check over your truck with a fine tooth comb.
i drive around alot with mine off but i dont normally have people in the back.

Check out this article on exhaust size:

http://www.hotrod.com/how-to/engine/ccrp-9812-2-quarter-inch-exhaust-3-inch-exhaust/

Kinda looks like big pipe/low back pressure more power up high. Smaller pipe, higher back pressure better power down low. Remember it's a rough guide and will vary from engine to engine.

hulk88surf wrote:Thanks for the advice everyone, 2" will do fine I think. Another quick question to any 1st gen surf gurus, is it legal to drive around with the back canopy off?

yes but depends on the cop......