Inline w/Split Exhaust, "tuning" the sound, effects of different size/length pipe

I'm planning the exhaust in my head for my 235 in King Of Trucks, my 55 2nd Series Chevy. Right now, I have the factory carb/intake/exhaust manifold. The exhaust is cobbled and ends in a gl***pack under the cab. The sound of the exhaust is relatively quiet and ****s. In a week or so, I'm installing an offy intake with 2 Rochesters and a true split factory exhaust manifold. I have three or four ideas for exhaust routing I'm playing with strictly for aesthetics. More than anything though, I want that sweet music. I'd much rather have sound over performance.

I want to hear from those that know.

How does exhaust length and pipe size affect the sound? Also, how about placement of the tips? For instance, would it sound like **** with both pipes exiting on one side? Or exiting in front of the rear wheels versus out the back, which sounds better? What size and length pipe makes what sound? And seperately, same questions in regards to performance. And finally, if that wasn't enough, what's the best combination of size/length/placement that will have the best sound and performance? I'm more than willing to sacrifice a little performance for a meaner sound, that's what I'm after.

Help me get it right and I'll post a hell raisin' video when I'm done. As always, thanks for the help and thanks for this great place!

 

You'll need :
One pair short steelpacks - 17" will rattle windows, 26" - 30" are deep & mellow.
1 7/8" (or 2'') headpipes
Mufflers as far forward as possible.
1 3/4" tailpipes for rapping; 2'' for the deep "motorboat" burble.
Tailpipes to the rear, straight out & on the left & right.
There'll be other people telling you to run straight pipes - they sound cheap compared to old days steelpacks.

 

I did the same as mentioned above but with one straight pipe and one with a muffler. with two mufflers it did not have the rap i wanted, and both straight was a bit to loud.

 

Stacks if it's a stepside

 

Please elaborate.

 

A friend ran the tail pipes to the rear of the car, and then forward to the rear axle , then back to the rear bumper..........he won rapping contests all the time.

 

I run a 302 jimmy 6 with a 6-71 blower. It has cast nicson knockoff headers(which can't be seen unfortunately). They are 3" outlet that is stepped down to a 2" pipe. The dual exhaust go into Smitty's mufflers and then they have a long run to the rear. I ran them both on the same side and they exit next to each other. It sounds amazing and has a lot of rap. It has a nice sound at idle too. When I step on it on the highway she moves and sounds really good.

 

Handy Hint:
If you split the stock CI exhaust manifold 4-2 instead of 3-3
it sounds way better and different, more like a V-8.

 

See, that's why I like the "traditional" split exhaust (3-3) on a stovebolt. Because it doesn't sound like a V8. The uninitiated wonder and ask what kind of motor it is. It creates smiles and opens doors.

 

i didn't notice if you were running 3 on the tree or not. just to make your decision harder, you may want to consider the drone you will get while in 3rd gear (if you're not using an overdrive). at "highway" speeds it may sound like a bees nest inside your car with open pipes. no matter what though, run the pipes out the back so the sound is mostly behind you. i have them on the side now and would not suggest it.

 

How do you do that split?

 

I've been trying different combos for 5 years trying to get "that sound" which, is probably not the same for everyone.

What I've got now: Fentons, 2" pipe all the way (don't use anything larger), the p***enger side headpipe crosses just behind the clutch inspection cover, 22" Smittys and long tailpipes (mine is a truck, the tailpipes start at the break between the cab and bed), tailpipes exit out the back. They have a nice mellow tone at idle and part throttle, but when you stand on it and go through the gears, they rap like anything.

 

Something most folks have forgotten or never knew ... a Chevy or Plymouth 6 with a split manifold & 17" steelpacks does it's best work on deceleration when set up right. Good luck finding any 50 - 60 year old Dougl***, Fenton, Hollywood Deeptone, Huth, etc. mufflers. The currently manufactured mufflers aren't constucted like the old ones were. Do a search for "Smithy muffler", you'll see a cutaway of how they were built 60 years ago.

 

You'll get as many opinions on this as about music itself.

I have 2" pipes from my cast iron headers into 22" Smithy's. The Smithies are as far forward as possible and reversed. Tailpipes are 1 3/4 to the bumper.

Sounds like an Italian sporty car down low and a fighter plane in a dive when you give it the beans.

 

X2 Ive heard of this for years, but aint never seen it done. Aint smart enough to figger it out.

 

Thanks guys for the info. I got all my gaskets to do the intake/exhaust/carb swap and I have the intake and carbs. I'm waiting on my split manifold to get here to start the swap. Since it'll probably take me a few days to build the full exhaust and I still have to drive in the mean time, I'll make two straight dumps about two feet long to run while I build the real thing.

My main concern besides the sound is keeping everything but the exhaust tips hidden. I hate to look at a car or truck and see the exhaust hanging down.

What about crossover pipes? Anybody use those and how do they affect sound? I saw some on the "why a split exhaust" thread a got to wondering.

 

I'm with Bwalls Terd, I'm running split pipes, 20" gl*** packs and a 2" tail pipe exiting in front of the rear wheels and whilst it looks great and sounds bad*** through the gears and scares the **** out of the venice bums as I change down going through the lights it's deafening at 65/70 0n the freeway in third......it would have been much more useable straight out the rear.

 

I know you know my opinion but I thought I would share my thoughts with the rest of the world.

Homemade headers on a flat 6, 1 7/8 pipe with Smithy's halfway back with an open pipe that byp***es the mufflers but flows in sync with them. Out the back the sound bounces from left to right in stereo. I ****in' love that sound.

I am happy with the way my flattie sounds.

As for the crossovers I seem to think they will blend the sounds too much and you'll loose that cl***ic straight 6 song.

Both out one side, again I feel you'll loose the sound but they do look cool.


One thing I can say from experience is if you run open pipes out the sides you'll get sick of them. As you know I had over 25,000 miles on my lakes and couldn't stand them anymore. Removing them and putting all the noise out back was the best thing I could have done.


Heres a shot of what it looks like under there. This was when I was running the lakes and cut outs;


Without lakes but with open byp***es from the cut outs and mufflers;



Let me know if you need my boys number.



******Knuckles

 

Hahahaha. One of the big redeeming qualities of my old truck was the sound of the exhaust. It had straight pipes with no mufflers and exited just behind the cab. I LOVED to hear that thing talk. Of course I had to make sure the radio was louder than the pipes for when I wanted to hear the music though. But I like loud music too, lol. You know how I do it.

I will need to talk to your guy. I got all the gaskets today. Just waiting on the exhaust manifold to get here, should be tomorrow or early next week. When it gets here, I'll go see your guy and get some sticks.

 

I'm running a Fenton header, dual 18" gl*** packs and pencil tips on my '56 (sedan). There's nothing like the sound of a stovebolt runnin' dual gl*** packs.

 

Ok guys, I've got a bunch of opinions and am no closer to deciding on my exhaust. How about some videos of your setup with a brief description? That would be awesome, I know they're out there!

Thanks again.

 

1 3/4" to just behind the ****** and then drop down 1 1/2" straight out the back.

http://s151.photobucket.com/albums/s153/flips07/2nd%20Album/?action=view&current=tony032.flv

 

http://chevybombs.net/forum/index.php?topic=8654.0

 

you can't split a chevy 4-2,only 3-3. a ford has to be split 2-4 or 4-2.

 

Back in the 50's we brazed a second outlet on the exhaust manifold and brazed a divider plate between the 3-3 set-up. If you drilled a 1/4" hole in the divider plate the sound was more mellow; no drilled hole it rapped more. Used Douglas steel packs with 1-3/4" pipe. Closest sound today since Douglas no longer available are Brockman steel packs.

Jim

 

'53-'54 Corvettes came stock with 4-2 split exhaust. My boss has a 54 Vette that sounds like it has asthma.

 

Really?? 4/2 split? Sounds cool

 

Actually the 6 cyl. Vette exhaust sounds terrible. Sort of like there's a nice sound in there somewhere but it's straining to get out. We've also got a 47 Plymouth and 53 Chev, both with 3-3 splits, and they sound great. I think they have 27" Smithys mounted just aft of midway back.

 

I was going to suggest the Brockmans, or take a look at Porter mufflers. They're a steel pack, and sound great, they've also got a bunch of sound clips on their site. I'd say 1 1/2 - 1 3/4 pipe. I love the sound of a split six.

 

All right....let's end this right now. I've got a factory Corvette 235 split exhaust manifold, and it's three and three. Since a 235 has four exhaust ports in the order of 1-2-2-1, how could you achieve a 4-2 split even if you wanted to?