Inliners International Forums General Discussion Engines Exhaust pipe diameter?

I have just installed a set of Norco headers on my 235. I have a Petronix upgrade and a 32/36 Weber. I was wanting to run dual 2.5" pipes but don't know if it might be too big. I do want it to sound and look good but also don't want to kill all of my torque. Any expriences or advice would be appreciated.
Thanks to all,

------------------
1962 Chevy Bel-Air, 235 L6, 3sp on the column

I think 2" pipes will be better.

Just FYI, the factory 375 HP 396 v8 in the Chevelles had 1 7/8" dual pipes, and they didn't have too much problem putting down the power. I doubt you'll need anything bigger than 2" on yours.

------------------
David
newbie #4153

Use 2". Check the distance between your bolts allowing for nut clearance, I'll bet you can't run 2 1/2" even if you wanted to. I know I can't on my iron Fentons, at least not without making extra adapters like on V8's when they want to run larger pipe diameters. Not worth the trouble for street use.

Just a 6, I had a 69 Chevelle 396-350 hp back in 71, the pipes were certainly bigger than 1-7/8 inch, 2-1/4 tailpipes as I remember.

I ended up doing a 2 2inch y-pipe into a single 2.5 inch pipe. It worked great and sounds goods. Thanks to all for the input.

Yuuuup! I have a similar set-up. For mild L6's I believe it works. And it does sound killer!

Ctown

Bigger is definately better when talking about "seat-of-the-pants" torque and HP increase. The faster you can get fuel and air in, burned, and out the back, the faster, you'll go. It's physics. If you want an deep, thunderous exhaust note, go big.
When I installed my motor, it had true duals, no "x-pipe"(they will quiet your exhaust)2.25" mandrel bent exhaust pipes straight out the back. It sounded nice at idle and barked at throttle. I was seeking the "Big-block" rumble at idle and car alarm wailing at open throttle. I achieved this level by simply adding 14" long x 6" diameter tail pipe extensions. This gave it the deep rumble at idle and true straight thru Inline roar at throttle. I also am utilizing 18"x3" chambered mufflers from the 60's vintage Corvette side pipes. One hell of a sound!

RapRap
1940 Chevy Coupe

[This message has been edited by raprap (edited 06-04-2003).]

To you guys with 2 into 1 exhhaust setups:

Can you describe the sound as compared to true duals? I am guessing it woudl be similar to an original Datsun Z, or Triumph TR6, with kind of a smooth aggressive tone vs the rapping of dual pipes?

Do you have any wav or other recordings?

Thanks,

Nick

It is a very smooth sound, not very loud at idle, used a Mellow-Tone muffler which gives a sort of tinny sound of a chambered muffler. I would highly reccommend this setup. I may be kinda partail because it's mine but I think its the best sound from less than 8 cylinders that I have heard.