Exhaust tube Diameter
 

Well it's me again needing a little help from my Chevy community. Question of the day for me is now, that i have these new high dollar headers for my 79 c10. What size pipe to run for around 450 to 475 flywheel horses, yes i like the 3" but do i really need to go that big for this? I was told by some that 3" will give me more noise. Looking to not upset neighbors but dont wanna choke off my truck either going to small or getting 3" and not need it. The headers are the Hedman 1 3/4 runners down to which ever collector i wanna use 3 or 2.5.

Re: Exhaust tube Diameter
 

At that power level you are getting close to the point where you need 3" duals, but 2.5" duals will support it if that's the route you choose. Use mandrel bends and good flowing mufflers. I'm at the same power level as you and went with 3" duals just so I know I don't have a restriction and have room to grow. They definitely are a little louder than 2.5", but muffler selection will have some to do with that as well.

Re: Exhaust tube Diameter
 

+1

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I'm running 3" duals on mine and they are a little loud but more of a deep tone. I's say go with the 3" duals. That should be great for the ponies you're runnin.

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i quite enjoy my 3" duels.
my neighbours do not.

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^x2

Adding tail pipes to my 3" dual system on the C-10 that used to be turned out in front of the rear wheels really dropped the noise level down. It sounds nice now when before it was a little loud and you didn't really get much of that classic Flowmaster sound.

I used to knock things off the wall of the neighbors house when I fired it up, with the full tail pipes it just shakes the windows when I drive away.

It has much more of the classic Flowmaster sound now.

Flowmaster makes a nice 50-series SUV performance muffler that will help quiet it down a little vs. the traditional 40-series muffler. I really like the way they sound on my Malibu and have a set I am putting onto the 68 Camaro.

Re: Exhaust tube Diameter
 

For mufflers you might try the Aerochambers. I know quite a few guys on here a couple years ago were switching to them and liked them a lot. They have a straight through design where the Flowmasters do not.

Re: Exhaust tube Diameter
 

Thanks alot i will check them as well. I was looking at the magnaflow mufflers oval 5x8 to dampen some of the noise. I knew for sure i was not about to run the flowmaster's. Thats the U2 mufflers on the shore. LOL (I'm running flowmasters, yeah U2) LOL
Nothing against flowmaster they are great but just want something different.

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I think i will do the 3" just run a different muffler, flowmaster also makes a 70 series that is next to the hushpower, but i was told they are to heavy and often break hangers. 3 i think is the way to go though. Thank you alot.

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I know there are several better flowing mufflers out there but I have been running Flowmaster mufflers on all the vehicles I build for over 20 years because I like they way they sound.

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is anyone having RESONANCE problems with the larger pipes?

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Only in the walls of the house before i put the tail pipes on. It was way louder in the house than it was outside. Kind of weird.

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I cant say anything bad about flowmaster they sound great, its just that over here everyone has the same sound. I wanna be a little different.

Re: Exhaust tube Diameter
 

Nothing wrong with that. The Hooker Aero Chamber mufflers sound a little different and are priced similar to the Flowmaster.

You could do a search for Aero Chamber on youtube and probably find a few video clips so you can hear them.

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Also, the magnaflows are straight through but very mellow.

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Do you have a dyno slip saying you make that much? Not doubting you, but i see alot of folk slap on alot of bolt on and stuff and think that all the crap added togeather adds up to 400HP..lol when really its maybe 30.added HP. post up a list of what you have done. really for anything streetable with decent HP you only need 2 1/2 dual , you really want to keep the exhaust gas velocity up so it helps pull everything out of the Cyl when the exhaust valve opens up. good article to read about exhaust.
http://my.prostreetonline.com/forums...ead.php?t=1639

Re: Exhaust tube Diameter
 

i got 2 1/4 in pipeing with flowmaster 40s.how much hp will i piick up when i put in the longtube headers?
its just a 305 with nothin that good in it

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Not much with a stock 305. Maybe 5 hp. 10 if you are lucky.

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I'd run a 2.5" y-pipe into a 3" single

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Go 3". I'm a Magnaflow fan. I like the smooth, mellow sound.