NeverBX

the si in canada is equal to the us ex, goof. obviously he is in canada cause thats where EL's reside.

nose

lv01109, good info, thx.

Is your gas mileage significantly worse? I just remembered we have a drive clean program that tests your emisions anually. Any idea if the exhaust mods overtax the catalytic?

lv01109

My car is an American 2000 Civic Si (with the 160hp B16A2 engine). With my I/H/E the fuel economy is the same (if the car is driven the same). I get 26 city and 31 on the highway. However, this is totally dependent on how you drive. If you drive the car harder, the fuel economy will decrease. My fuel economy drop has not been measureable.

As for the performance, my Comptech & Mugen I/H/E combination has made a fun car even more fun. My Si has more low end torque and starts off easier in 1st gear. The car also has more torque in the mid range so it pulls up hills better in 5th gear when crusing at ~55mph. However, the Mugen exhaust is better in the mid-range than many exhausts but it sacrifices 1-2 hp on the top end (much quieter on the top end than most also). When VTEC engages at 5700 rpm, the improvements are still very noticeable. However, do not expect the car to behave totally different with only an I/H/E. If you want a lot of torque from a 1.6 liter, the only way to get it is with a turbo or supercharger.

If you've got any ideas about my sunroof rattle, please advise.

Slipjack

Yes you would need the whole I/H/E to really get anything. They all work together. Having an aftermarket header with stock exhaust is like trying to attach a straw and a waterhose together. That straw is only going to allow a certain amount of pressure. (Sorry, best analogy I could think of). But when you have all three you can expect anywhere from a 10 to 20hp gain.

nose

Can't help you with the sunroof, although I fixed a lot of rattles in my '88 civic by cranking the stereo.

Thanks to lv & slipjack for the input. I'll do some pricing and see what the damage will be.

NeverBX

as far as the sunroof it could be just loose, or maybe a shim fell out.

Ronin

IF you do I/H/E you might get 10 hp. You also might get a high flow cat to go along with those things. What you could also do is try to drop some weight from you car. The best kind of weight to drop is unsprung weight. That is stuff around the suspension and wheels. You will feel those 10 hp better if they have less weight to pull around. Even though unsprung weight is the best to drop any weight loss will be helpful