Just wondering what kind of effect on performance having an exhaust leak between your downpipe and cat will show.

The gasket was bad and was leaking air big time.

WADAD

 

at that point in the exhaust system, it shouldnt make too much of a diff, a little in the low end and it wouldnt hurt in the topend. how big was the gap?

 

Not a big gap.

Just enough to let hot air out if you held your hand there. Made the car a little louder.

WADAD

 

yeah it shouldnt make much of a difference then. you feel a differnce when driving?

 

I'm not sure. I am trying to figure out if the exhaust leak helped on my top end performance. The 2.25 custom catback was supposed to improve things big time over stock piping but hasn't really happened.

WADAD

 

I would think it actually hurts the top end a good bit. Instead of the gasses traveling the full distance of the exhaust it terminates early and doesn't give the same amount of push.

 

we aren't talking about a rocket or jet here dude, the expulsion of gases don't effect the cars movement

 

yeah, but a 4 cyl depends a fair amount on having backpressure

 

Id say it hurt him a bit. That whole backpressure crap

how did u find out? did u change it when u installed the catback?

 

So backpressure plays no role in power then?

In that case I don't know why companies spend r&d money on testing flow characteristics of manifolds and exhausts.

 

i didn't say that, however, but if you'd like to take my words and twist them to fit your agenda go right ahead rocketboy

 

rocket man...

 

dont insult or try and argue with a knowledgeable well-standing member, n00b

 

So just how much backpressure is needed to ensure good power then? Is it ok to chop the exhaust off at the end of the downpipe? Will that provide better gains than a full exhaust?

There's people that have done things like chop off exhausts from cars because they "heard" it would provide gains since it removes restriction. Companies have turned around and dyno charted this method and guess what? Doing that lost hp and tq all across the powerband instead of providing any gains.

So I'll ask again, how much do you know to validate your original statement?

 

Yes I found out I had a leak when the catback was installed. I used to hear the car backfiring slightly but thought it was the header opening things up.

WADAD