TCCoA Forums banner

1 - 15 of 15 Posts

·
Registered
Joined
·
1,430 Posts
Discussion Starter #1
i have been thinkin about exhaust for a while now, and i have been contemplating what i should do. Ppl here seem to like Magnaflows. I have an idea, ill buy some magnaflow mufflers off of jegs.com or somethin an take it to a muffler shop an have them install a custom catback, but i have some ?s. First off, i was thinkin as a b-day present (which is in June)from my parents is to get the exhaust done, but it might be askin for too much. SInce i live in the smog nazi state in cali, im keepin the 3rd cat, no ifs ands or buts about it, im keeping it. Now ive read 2.25 is the way to go from the 3rd cat back to the mufflers. Since i have a 97v8 theres no resonator. Should i replace the downtubes from the 2 primary cats, to the 3rd cat? If so what size should i tell the shop to use? and how much more for using mandrel bends on the downtubes instead of compression bends? Tell me waht u guys think, about this setup will it have problems with emissions?
 

·
MaleWhore
Joined
·
2,640 Posts
well emissions seem weird to me since i live in MI, but if i were to get everything done...either go for tru duals, with cats...or just replace the cats with high flows or something, coming into a 2in one out muffler...just splitting out in the back again...i wouldnt really know what would make u pass emissions or not, but someone here would be able to help you...(...and if u were asking ur parents for a exhaust...tru duals might be a lil to much if u buy the kit from art...so the other method might be cheaper...)
 

·
Registered
Joined
·
1,430 Posts
Discussion Starter #3
i cant go with true duals, for two reasons, one is price, two is ill repeat, i live in CALI. I will fail a visual more than likely. What size downtubes do u guys recommend, i am considerin mods in the somewhat distant future. 2.5" downtubes to the cats? will it affect my emissions by doing a custom catback with magnaflow mufflers 2.25 inch and bigger downtubes?
 

·
Registered
Joined
·
1,430 Posts
Discussion Starter #4
The dynomax catback has 2.5 to the y pipe then splits to 2.25 to each side. Thats the way ill prolly have it done if i have it done. how big should i go on the downtubes or should i leave them stock? Also, will going with ultraflos make my car obnioxously loud? I want it somewhat loud, but not too loud. Are ultraflos CARB legal or not? Magnaflows?
 

·
Administrator
Joined
·
4,161 Posts
There's no such thing as CARB legal or illegal mufflers. Anything you do after the cat is smog legal so long as it's noise legal too.

Also, there's no point in messing with anything before the 3rd cat if you're going to keep the factory cats. The only thing worth doing would be to add aftermarket high-flow three-way cats. If you do that, you'll have to document what you put on and explain that your factory cats were either worn out or that you ran over something that destroyed one of them or something. :D That's the only way you'll get a smog-legal front exhaust.
 

·
Registered
Joined
·
1,430 Posts
Discussion Starter #6
Sir William said:
There's no such thing as CARB legal or illegal mufflers. Anything you do after the cat is smog legal so long as it's noise legal too.

Also, there's no point in messing with anything before the 3rd cat if you're going to keep the factory cats. The only thing worth doing would be to add aftermarket high-flow three-way cats. If you do that, you'll have to document what you put on and explain that your factory cats were either worn out or that you ran over something that destroyed one of them or something. :D That's the only way you'll get a smog-legal front exhaust.
cool. I think ill go with ultraflos. Awesome the president of TCCoA responded to one of my posts:uppoint: :D . Ok, not even replaceing the downtubes with mandrel bent pipes will help there, cause ive heard its a very nasty compression bend to the 3rd cat, wouldnt a mandrel bent help there?
 

·
Registered
Joined
·
1,430 Posts
Discussion Starter #7
ok, my dad has this stupid idea in his head, and im bout ready to slap him upside the head with a damn bat! He thinks that putting a catback system from the 3rd cat back, will make the car "run differently, or in other words hurt the car." he thinks it will mess it up for some reason. I swear he's so misinformed it isnt funny, and when i rebute what he says he says a smart *** comment,then gets angry it drives me nuts. Please put this theory to rest....:leftright
 

·
Registered
Joined
·
1,430 Posts
Discussion Starter #9
well my dad said i should have my uncle do it (who is a master mechanic), but i dont wanna bother him with that, theres plenty of exhaust shops here in town, so that is kinda pointless. What is better dynomax ultraflos or magnaflows? If magnaflows which one, and will my car be sorta loud? Sir william says installing bigger downtubes to the 3rd cat is pointless, i wonder why that is and how big r the stock downtubes?
 

·
Registered
Joined
·
2,806 Posts
If you are intent on having all the cats, one thing to think about is that LSC's came with a two in/two out third converter. Its one option if you want to go true duals emisions legal. Also check out the tech articles' exhaust section for proper pipe size for the power you have or plan to have.

-Miller
 

·
Registered
Joined
·
1,430 Posts
Discussion Starter #11
hmm, the stock downtubes are only 2 inch, it would probably help to go with 2.5 inch on the downtubes, then have a 2.5 inch after the 3rd cat, then split into 2 2.25 pipes.
 

·
Administrator
Joined
·
4,161 Posts
A chain is only as strong as its weakest link. So too an exhaust system only flows as free as its smallest restriction. The inlets to the 3rd cat are 2". So why come from 2" at the primary cats to 2.5" for about 18" then back down to 2" at the 3rd cat then back up? It's silly. The only thing different will be the weight of your wallet after that change.
 

·
Registered
Joined
·
1,430 Posts
Discussion Starter #13
well as u said, i cant replace the Cats cant be replaced unless they r bad, so i guess i wont do that then. Thx for your advice. But wouldn't replacing the downtubes with mandrel bent pipe instead of compression bend help out? Ive heard guys say dynomax ultra flows are good mufflers, but what magnaflow mufflers are good for these cars? I want something moderately loud, but not too loud that it becomes annoying.
 

·
Administrator
Joined
·
4,161 Posts
The bends in the factory downtubes still don't restrict enough to warrant replacing them if you're going to leave the 3rd cat. Sorry, just leave it alone and work on the cat-back.
 

·
Registered
Joined
·
1,430 Posts
Discussion Starter #15
well then looks like a cat-back it is, what sounds/ flows better dynomax ultraflos or magnaflos? Which magnaflow to get if magnaflow?
 
1 - 15 of 15 Posts
Top