i was wondering i have an em1 and was wondering if it would sound better if i leave the si muffler or i also have a gsr muffler which one should i use

 

A few people do this, exhaust sounds like stock until you punch it. I would guess the GSR one flows more due to a bigger engine (1.8) but that's just a guess. Or get a RSX-S muffler, I've heard those sound a little better. My friend has one for sale, pm me if ur interested.

 

how much does your friend want for his muffler?

 

What's the point? The exhaust is only as good as it's weakest point... i.e. the smaller diameter muffler.

 

it will sound raspy... i have 2.5" to a stock axle back on my 92 gsr and it's stupid raspy above 3k rpm