B3 exhaust

[micro_trucktiva]

Is 2.25" too big for this 1.3l? I'm pretty sure it has a 2" exhaust right now with a magnaflow muffler and stock cat converter. or should I stay 2" and replace the cat with a "highflow" converter?

[bhazard]

I wouldn't mess with it. Keep it quiet, is a 63hp engine.

[Damkid]

[micro_trucktiva]

I don't like quiet....lol and I'm trying to make it as efficient as possible.

[bhazard]

Loud is not efficient. Thats a proven fact. The car already has an exhaust thats probably too big for the B3, and a straight thru muffler. If you open it up more it'll probably sound like a fart can honda.

If you want to learn how to make the car more efficient check out the ecomodder forum. Theres a guy on there getting 60+ mpg out of a festiva.

Just my opinion though. Personally I think slow cars should be quiet.

[Damkid]

^^i agree a nice sounding car is always nice to have, no matter how slow it is

[bhearts]

If you read into exhaust size and peak torque levels any, especially in a header, you find that bigger pipe helps with top end flow, but hurts low end torque. Where as smaller pipe hurts top end, but primes the cruising rpms for max torque capability. So going 70 down the highway with a 2.25 inch exhaust could net you a 10 inches of mercury vacuum rating. But a 1.75 inch exhaust you could see higher vacuum numbers at cruise. Higher vacuum equals less throttle opening, equal to better fuel economy. Ironically though, slapping a better breathing air filter in could also net you higher vacuum numbers. But... to maximize the intake for mpgs, you'll actually want to situationally delete your throttle body. When you think about it, nice flowing intake tracts help with fuel economy, but your throttle body is one big block in the road, it's an intake limiter. Warmer intake charges are less dense of oxygen, so you'll actually have to give your engine more throttle to keep its speed. That's the idea of the day. Controlling engine speed with oxygen flow, directly manipulated by the medium temperature.

[micro_trucktiva]

So stick with 2 in diameter then. Ok

[march]

i think the same way micro say. 2" diameter to my opinion is to big if you dont have any mods.