I am seriously thinking of buying a Hooker Aerochamber muffler for my 92 Firebird 305 TBI. I currently have a set of Hooker Competition headers with a custom y-pipe and all the emissions crap gone. It still runs through the stock muffler, which is rusted and rattles like mad. I want to run a Aerochamber, but have a few questions first.

Is the interior resonance bad with this muffler? I have a 50-series Flowmaster on my Blazer that makes terrible resonance and I don't want to deal with that on my daily driver. I just want to hear it a little when I get on it from the inside and hear it a lot on the outside. It'll still be running the stock-looking tips or maybe a 4-tip setup like a 78 Trans Am.

Will this give me a good increase in performance? When I run the cutout open, it runs good when I keep the revvs up, but one I back out there isn't enough backpressure and it is a little sluggush.


Another off-topic question. Does anybody know of any good forums for 2nd gen Firebirds/ Trans Ams? I have two of them and can't seem to find the same wealth of info like I do on this site. Thanks!

 

There is minor interior resonance around 55mph, but around 60-65 it's real quite. Hope that helps.

 

I agree with Mark, it's not really loud when you're at cruising speed. I still have my wimpy 2.77s but it keeps the car at 1700rpm at 70 mph, so the Hooker isn't much louder than the stocker.

Hooker has a nice low burble at idle, and a real mean roar at WOT, not hollow and boomy like Flowmaster.
It also 'spits' if you blip the throttle when it's cold

 

Not all Flowmasters sound like that.

And you got to have lots of interior resonance!!

 

Thanks for the replies, fellas. I think I'll pick one up now.

No way, man! After my ear surgery, my doc told me I had to wear earplugs driving my truck. I hardly ever drive it, so I don't bother. I don't want to have my hearing go bad again from driving a loud car!

 

cruising at 55mph in overdrive I can barely hear anything...

 

Lol... Not as annoying as the interior resonance in a honda accord with a fart pipe and some other junk (no stickers, though. G0D i hate those stickers!)... That was my last car b/f i got my rs.

 

No way, gotta have the resonance. :rockon:

 

How about gettint the entire hooker cat back? This way you will have a 3" pipe into the aerochamber I love the way mine sounds.

 

I can't believe no one has caught this, backpressure makes a car sluggish, you don't want any backpressure.

 

Yeah, you don't want backpressure, but it is possible to have too little packpressure. If you don't have enough backpressure, you lose a little response.

 

You're still wrong, you're confusing backpressure with velocity, backpressure doesn't help even a little.

 

I personally don't know $hit about backpressure, but I'm just basing my opinion on what friends have told me. I talked to him about putting a 3.5" system, no mufflers or cats, straight off the back of my 75 Firebird's 354 Pontiac motor and he told me that it was too much. He builds race motors, 500+ horsepower, so I trust him.

 

Oh yeah, how much does that Hooker Cat-back system cost? Does it exit like stock or does it have the big tips coming out the back? I don't like the tips, I'd like to keep it looking stock.

 

You're friend is confused as well, this topic came up a while ago and was explained in great detail, I thought the same as you until others informed me. The exhaust, the cat-back I got the $200 one and had it welded on. It does come with tips out the back, but you don't have to use them, they're separate.

 

well, I think you guys can argue forever about the back pressure issue, but an exhaust system is a lot more dynamic than just back pressure. If you do something that reduces back pressure, but also removes something in the exhaust to "pulse" the wave back to the valve at a timed interval, you will loose power.

If you just ran a short straight pipe out of the cylinders on your stock motor, like a fueler, the car wouldn't get out of it's own way. Who's right? well, both of you are right in some ways. Back pressure is not desirable, but sometimes is a necessary side effect of powerband tuning.

In purely theoretical terms, you always want to minimize back pressure, but you can loose power while decreasing back pressure, if it moves exhaust scavenging out of phase or more literally, throws your combination out of balance. Even if the decrease in back pressure substantially decreases the temprature of the exhaust gasses in the pipe (which it does) it changes your tuning. Bigger is not always better, but that's what I would put my money on!

 

I believe that's what everyone confuses it with, which is velocity.