mine is using stock manifolds for now and it doesnt seem to b extremely loud...my friends 94Z has flowmaster cat-back and it is extremely loud inside and outside of the car...at 2500 or so it seems to just rumble throughout the car.....and i like that....so i was wondering that when i put headers on my car will it make my exhaust a lot louder?

or will i have to switch over to flowmaster 40 series for that type of sound?...cuz i like the hooker setup but i just want it to b loud like his


any advice would b great
thanks

 

Headers will make your car louder. My Hooker cay back was pretty tame with my stock manifolds. Even with the crappy flowtechs that I have the sound drastically changed and got noticably louder. This is with a cat to. You will be very happy with the sound with that set-up. The stock thick manifolds dampen the sound very well. Thin wall headers do not

 

I still have the manifolds for a little while, and it is quite as hell at idle. At WOT though it is still pretty loud, but not as loud as I want it. I had a buddy w/ a LS1 that had manifolds and the hooker catback. Was pretty tame until he added the headers he got, and WOW that car screams now!!!

 

good deal...yah i mean i like how it roars when u get on it but i just want all around louder sound...so it looks like the headers will do it for me
thanks!

 

the thickness of the material has nothign to do with it.

in the manifolds, the air (and sound) smack into this wall a inch and a half from the port, and do a 90* bend to meet all the other cyls and then go thru a small exit. the slamming and 90* turns have the same effect as baffled mufflers.. it takes energy (and therefore sound volume) from the exhaust..

meanwhile headers are much more efficent and the sound can "flow" with the air thru the exhaust alot easier.

if you were to cast some manifolds in a header like shape (like some newer cars have) then you would have the same sound.

 

so also along the lines of louder exhaust u are saying that it will not create as much heat since there isnt as much energy created by all of the friction and whatnot from that initial 90* turn in the manifold?

which wil in turn allow my engine to run cooler...right?

 

blow on your arm.. do you feel a massive amount of heat from the friction from the moving air?

no, the friction has nothing to do with it.

matter of fact, the underhood temps will be higher because the headers will radiate more heat.


but, more of the exhaust heat will go out too... really from what ive seen, it doesnt have too much of a effect on engine temp...

 

It is wall thickenss that helps dampen the sound. Trust me. The wall thickenss will dissapate vibrations more effectively. For pipe sizes that small the amount of fluid head loss that you will see will not change the turbitity and create noise. Thermal energy does not create noise. There is also less potential energy in the flow in manifolds as opposed to headers so the vibrations are different. For the same reason why you can't hear your neighbors though a concrete wall but you can through drywall.

 

The friction has a lot to do with it. When the exhaust gasses leave the cylinder they are almost at super sonic speeds. At super sonic speeds air friction is HUGE. Some aircraft skins will swell up to an .5" at mach one. You are 100% correct about radiating more heat though. The stock manifolds act as heat sinks and do not dissapate it as easy as headers do.

 

I have hooker 2055 no cat and the cat back and it rubles at idle just enough to tell there is cam in my motor, then at WOT it is crazy loud! Like old school chambered exhaust loud. The biggest restriction on sound I have found is the cat, once gone your motor will sound like a true muscle car.

 

I put on a hooker cat-backwith the stock manifolds and cat on and it was a little louder, but mostly had a better sound.

Once I put the Edelbrock TES and high flow cat on WOT is just plain nasty

 

Same here, I've got the hooker 2460's, high flow cat, and flowmaster 80 series and it's kinda loud at idle and screams at WOT. Sounds totally diff. inside and outside the car too.

Last week, I had my uncle take my car around the block and make a WOT pass to test something and it sounded like a damn pro stock car about 1/2 a mile off

I dunno why but my favorite sound is my CAI whistling from all the air rushing into it at WOT.:lala: :lala:

 

yah i gutted my cat cuz it was clogged and i gained a few things...some good some bad.....one, my exhaust DID get louder, secondly my car gained an incredible amount of power, and third.....now EVERYONE can see how old my motor is....after i gutted the cat i noticed about 3 times the smoke as b4

i cant wait for my vortec 350