high rpm popping

[NineOneQ45]

has anyone successfully tamed the higher rpm popping/rattlings sounds from free flowing exhausts? i'm not interested in spending the $$ on a high dollar aftermarket system, i posess the skills and equipment to build my own system. i'm also not concerned with noise level, just eliminating this popping noise. does it go away with the removal of the pre mufflers/resonators, or just get worse? is it just an inherent quality of the engine? my original plan was to remove the pre mufflers and put a dual/dual dynomax in the rear, but if i can't improve the popping while gaining a healthy v8 sound i'll just return it to stock.

[squeefoo]

I've been around Q45's since '98 and I have no idea what you are talking about.

Popping ??????????????

[elwesso]

Are you talking about like when you rev it in park, and as it comes down theres that sort of fluffy noise, wheres its like "ffffff fffffff fffffff"

I have a borla system and thats what it does.. i wonder what removing the premuffs would do?

[vicQ45]

my exhaust leak gives me that butterfly on crack sound. still think wes has the best idea with the electronically controlled caps.

[CrimsonQ]

I removed the pre muffs and replaced the rear muff with a 50 series flowmaster. Dont know if it pops or not, theres a sound clip floating around here somewhere............

[CrimsonQ]

here it is http://www.z-mation.com/DucksStuff/qexhaust.MPG

[PoorManQ45]

You need a crossover pipe to equalize the two sides

[NineOneQ45]

it's hard to explain. if you've ever heard a late model gm truck with straightpipes, that's the sound. it sounds ok at lower rpm and partial throttle, but open it up and it gets to ~5k it starts this aweful popping.Quote »butterfly on crack sound.[/quote]that's a pretty accurate description, lol. i'm going to replace the pre mufflers with pipe today and see what happens.

[elwesso]

I think like PMQ said replacing the H pipe with an X pipe might do the trick...

[NineOneQ45]

possibly, but i doubt it... and H and an X pipe effectively accomplish the same thing...

[Death by Mullet]

dude! that's a Q? sounds good, would be great with out that rattle or what ever.

Mullet

[PoorManQ45]

possibly, but i doubt it... and H and an X pipe effectively accomplish the same thing...

I think he said he's runnign straight pipes. Alot of people "forget" to put a X/H pipe in

[CrimsonQ]

its no rattle, its a resonator tip. also the engine and exhaust were cold at the time of the clip, ill post up one with the car warmed, sounds different

[CrimsonQ]

.ok exhaust broken in after 4 months or so, sounds a lil different. Still has the flutter sound above 4,000 rpm's. I love the way it sounds, but of course opinions always differ.sound by rear of carhttp://www.z-mation.com/DucksStuff/qexhaust1.avi

sound inside carhttp://www.z-mation.com/DucksStuff/revupQ45.mpg

[TgduMg]

possibly, but i doubt it... and H and an X pipe effectively accomplish the same thing...

Following excerpt taken from the Vette-Magazine articleThe "X" Files.

An H section is inexpensive to mass produce. It's better than no crossover or balance tube whatsoever, but it is fairly inefficient. Exhaust gases want to follow the path of least resistance--that's why smooth mandrel bends produce better power than crimped and uneven (i.e. the corner muffler shop) bends on exhaust systems. Unless forced, exhaust gases are not going to make the hard 90-degree turns you see on an H pipe. An H pipe will offer some benefit, but not a lot.

An X section, with gentle beds and an open center chamber, offers substantially better balancing or equalizing of the exhaust gas pulses than are possible with an H crossover. Ergo, an X crossover should, with no other changes, offer enhanced power production. It should also eliminate the burbling and popping on deceleration that's not especially uncommon on aftermarket C5 cat-backs. We'll see.

Danisiti 1

[NineOneQ45]

Quote »I think he said he's runnign straight pipes. Alot of people "forget" to put a X/H pipe in[/quote]uh, Q's carry an H stock. i dont know whether he cut his out or not, but the original comment was for me to add an H or X to eliminate this noise. i've already got one.Quote »Following excerpt taken from the Vette-Magazine articleThe "X" Files.[/quote]yes, that is true that adding an X to a c5 will eliminate the "popping" on deceleration. it cures it on many vehicles. no offense, but this isn't a c5 and i'm not experiencing this noise on deceleration.

in any event, i removed the other 2 mufflers today, added some pipe back to the diff area, and it is much improved. i believe once i finish the rest of the piping and get a muffler on the back it'll be ok. sure does sound pretty nice, almost like a late model mustang with exahuast (just a little higher pitched).

[ferran586]

I am new to the boards and will be buying a Q in the very near future. I was curious as to what the stock exhaust size is because I have a muffler that I had on another car and wanted to swap it over. This place seems really great and I hope to learn/teach alot here.

[PoorManQ45]

2.5in.

NineOneQ45: What did you remove? Did you remove everything after the cats? If so then you need a crossover of some kind. If you started at the mufflers then you don't NEED a crossover becasue there's an H there already.

[NineOneQ45]

2.5? mine is only 1 and 7/8 OD, IIRC. i just removed everything from the muffler inlets back. put some tubing back in place to the rear diff, and will finish it off the rear once i get a muffler to go back in the rear.

[PoorManQ45]

Where did you measure the diameter?

[Altiman94]

There is no way the Q exhaust is 2.5in stock.

[CrimsonQ]

the pipes i took off on my 90 were 1 3/4