2.5" or 3" w/ flow 80 series?

[lookout4theyeti]

Im gonna be calling around some exhaust shops soon looking for some prices to have a flowmaster 80 series muffler put on with some new piping. Should i go with 2.5" or 3"? I dont have any other mods as of right now, but do plan on new intake and headers. Also, i wont be changing my cat due to emissions here. So yea, just wondering which size would sound better? I want it to sound deep and loud, and not ricey at higher rpm's, which i hear is a problem with the 80 series. Any input helps, thanks guys

[Little G]

someone just posted about a 3" Magnaflow that sounded pretty good. I think the trick is getting a bullet muffler in addition to the cross-flow muffler to filter out the rasp. However, it will still sound unmistakeably v6.

[tWiStEdBird]

If your looking for sound, 2.5 hands down. If your looking for performance 3" (Although some would argue). It's really up to you, but I would suggest 3 if your planning on future mods.

[tWiStEdBird]

And just fyi, stock is 2.25, so 2.5 is only .25 larger.

[FireFighter]

Originally posted by tWiStEdBird:
If your looking for sound, 2.5 hands down. If your looking for performance 3" (Although some would argue). It's really up to you, but I would suggest 3 if your planning on future mods.

3'' sounds better to. 3'' Hands down.

[lookout4theyeti]

well im looking more for sound, lol and i have one vote for 2.5 and one for 3 now.

[WickEdSix9838]

3"...will run quicker and sound better.

[grayman]

3" is more involved to install. 2.5 is built for your specific year and easier/more affordable to install.

3" = new 3/3 cat is needed...you will get SES code...will not pass emissions if OBD2 testing. (you will have to add sim to install price)

This 3" LT1 magnaflow sounds real good...BEEFY to say the least. The bullit muffler DOES reduce rasp to pretty much nothing.

Older v8 catbacks such as the magnaflow LT1 v8 (1993-97) come with the s pipe. Later years use welded cat so they don't come with the s pipe...those kits need a conversion kit...SLP has it I think.

[00firebird]

wheres this video of the magnaflow i missed it...

[lookout4theyeti]

Originally posted by grayman:
3" is more involved to install. 2.5 is built for your specific year and easier/more affordable to install.

3" = new 3/3 cat is needed...you will get SES code...will not pass emissions if OBD2 testing. (you will have to add sim to install price)

This 3" LT1 magnaflow sounds real good...BEEFY to say the least. The bullit muffler DOES reduce rasp to pretty much nothing.

Older v8 catbacks such as the magnaflow LT1 v8 (1993-97) come with the s pipe. Later years use welded cat so they don't come with the s pipe...those kits need a conversion kit...SLP has it I think.

hearing this, i think im gonna go for the 2.5"...i dont feel like dealing with emissions here, and i dont wanna have to replace my cat right now.

One last question, im pretty set on the flowmaster 80 muffler, do you guys recommend something other than that? or should i just stick with that

[FireFighter]

You have nothing to worry about with emmissions, I have no idea what he is talking about. You will NOT get an SES light from a GOOD high flow cat like carsound/magnaflow.

Also I have no idea why he is saying easier to install and it will only cost a few bucks more.

Thats some of the worst info I have read on this board in a long time!

[V8 Killer]

3 inch and high flow cat!

[Iwantafbodyagain]

I see everybody recommending 3" exhaust.
Somone show me an article that has before and after dynos, of 3" exhaust on a STOCK 3800. Prove that it makes more power then the 2.5 system. FYI, the 2.5 flowmaster system for the 3800 makes 11RWHP, proven by Popular Hotrodding.

http://www.popularhotrodding.com/tech/0305phr_v6/

"The American Thunder exhaust for V-6 F-Body cars worked on the DynoJet chassis dyno to the tune of almost 11 hp at the rear wheels, which is nearly a seven percent improvement. Using a Vericom VC2000 Performance Computer, an on-board, vehicle dynamics testing device (www.vericomcomputers.com), we observed an improvement in 0-to-60 time from 7.83 to 7.44-sec. and quarter mile stats going from 16.15 at 89.14 to 15.87 at 90.69."

AND!! look at french camaro's video clip (in the video clip thread) it sounds beter then every exhaust posted their! he does high RPM shifts, with No rasp or popping.

[FireFighter]

I can't help you their, I was no where near stock when I dynoed mine. 2.5'' is a waste if you are going to do anything other than just intake and exhaust.

[pivot]

I am no expert but I owuld suggest the 2.5" and then put a cutout in for the performance. every 3" I have ever heard sounded like crap past 3k. I have the american thunder cat back with resonator and I think it sound very good. I am sure when I get a high flow cat it will sound better. It does not sound like a V8 witch I like it just sound like a V6. very good system in my book.