Exhaust question

Im thinking of getting a new muffler for my 4.8 Silvy. I dont want to spend much money though. I see on Ebay there is Flowmaster 40 series mufflers for like $45. But do I need the entire cat back system, or just the muffler. I just want it to sound cool, Im not really interested in getting big HP gains or anything like that. Is it worth just getting a muffler or and i wasting my time? Also is there any other mufflers worth looking at?

You can just get the muffler...it won't sound as good as getting the whole catback system, but it should work just fine.

What about sizes of inlet/outlet holes and offsets etc. How do I know which one that I need?

im not sure if its different on a 4.8 but on a 5.3 youd need a center 3" inlet and a center 2.5" outlet and probly some extra piping due to the smaller size of a flowmaster

on any newer chevy motor, the 40 series is not all that loud..i have true dual super 40s which are supposed to be louder than the original 40s and its pretty quiet

What size engine you puttin' in front of it?
That 40 series can be pretty loud on some trucks.

Mines a 4.8 litre. I love that engine, It blows new Ford F-150 4.6L's off da road :D

go on ebay and check out this setup. cheaper than a catback, but you will need a cutoff tool and a friend to help you. but i got one of these and it sounds good and it only took us about 2 maybe 3 hours.
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&category=33630&item=7965182323&rd=1

Thanks sportin83, that looks sweet.

Do yourself a favor and do it once correctly, get STAINLESS STEEL. Aluminized will rust within a year and you will do it again. Just look at the other posts. My truck had 40k and the aluminized were rusted so bad the guts fell out of the 40 series muffler. I bought a stainless Bosal and could not be happier. Just my :2cents:

I welded up a flowmaster 40s single in duel out muffler on my 4.3L silverado bout a week or two ago , only have 2 10" length tube coming off the muffler (everything hidden below truck basically). I have videos of me testing it out in car video section if you wanna hear with it sounds like