Projects Exhaust suggestions for mild (330ish HP) SBC 350

The plywood has a rubber (hard) layer over it.

 

That's an option I guess, but the mani's will likely be 2-1/2, so unless the bends are difficult to get good clearance and such, I hate to decrease. Maybe that is ok. I'm not the exhaust or engine tuning pro, which is why I'm here. I do realize for street cruising I won't notice much of any of this....

I disagree to an extent as your C10 is likely coil front suspension, I have torsions and an X-frame working against me. Just not much option to run that exhaust down and back. That said, I do realize some with my same suspension and frame set their frames on the ground, but at what cost and how much mod'ing? I've seen some that seem to have the X member notched for the exhaust to run through. I don't have that privilege.

Right now as things set my torsion keys are the low point on the frame/suspension/exhaust, BUT I want to get them re-indexed to get them set back up into the cross member instead of hanging down. If that happens, then it'll be my exhaust pipes that are the low point. I'm guessing as is they are about 4" off the ground. That worries me some. Again, I realize others are low, in fact back in H.S. I was into mini-trucks and had a toyota that I completely pulled the torsions out of and let it sit down and then we stuck them back in while it was sitting with zero suspension on that thing. The front cross member was a static 1/2" approx off the ground. I'm not sure there was much lower back then, I had most of the bugs beat and they sat those things literally on the ground.

Maybe tomorrow I'll run it by the 2nd shop and see what they say. Depends on the weather and how my day plays out.

 

My hard rubber layer is gone, it was overlayed by this and that and all of it was nasty. I wouldn't mind going back to that look IF i could find it. Any idea?

 

Hope this shows up. Here's how it's currently ran.

 

Yeah, I have these on my A pickup, and they sound great. But they are kinda loud maybe for this application. But I've recommended these on other threads, run the augers in the collectors, then run a 2 1/2" out to the rear bumper, that would be an outstanding exhaust, very free flowing too. You could always add resonators if it causes a drone at hwy speeds. This is not a bad way to go at all.

I think he's referring to a 4 speed automatic, which are overdrive transmissions. But as 31Vicky posted, the real advantage with these is that you can use shorter gearing in the rear end for quicker acceleration then drop the rpm's at hwy speed with the OD top trans gear. But unless the OP has some serious short gearing in that Burb, which I don't think he does, 1:1 top gear of a TH350 is fine for hwy use.

 

I have a 3.90 Posi in the rear.

 

You're probably right. Not many use the term "4 speed" like the OP did.



To the OP,

It sounds like you've got your mind made up on certain aspects of the topic that are impervious to external input. Best of luck with your project.

 

No.........IMO cost of H-pipe not worth it.............don't notice any difference on my 383 w/ramhorns, also have 383 in my 57 using shortie headers..........in fact, I was told many years ago that ramhorns flowed so well that headers only benefit your horsepower over 4000 rpm..........

 

I once drove a 69 Camaro 427 ZLX Big block 4 speed car from Colorado springs to Detroit with 4.88 gears and Hooker side pipe headers. The radio was worthless as the exhaust was too loud , but I had a heck of a passing gear . Gas was around 65 cents a gallon so it was a non issue even on a army salary. Just came back from Nam and had saved my money for almost 2 years. Stopped to visit several Army buddies along the way and they had to go find the baddest car in there town so I could shut them up.
So don't say you can't take a trip with you 3.90 gears.

 

have you changed the manifolds yet?
You said they were 2" ram horns on it now.

Most muffler shops have a squish bender. Have him bend a sample of 2-1/2 pipe and then measure what the OD of the bend is, it will be substantially smaller. A 2-1/2 manifold with a 90* squish bend in 2-1/2" pipe immediately after the manifold is not going to help anything and likely to make things in the breathing department much worse.

Clearance is tight here as well- this is for a 54 Chevy truck.
My muffler guy swaged the belled end manifold stubs for me, I split a 2" mandrel bent 180' U bend and had him swell the straight ends to fit inside 2-1/4" pipe and welded the stubs to the other.


You could do the same thing using 2-1/2" U bend to get started vs having him crush bend the first one.

 

This is what I have on my car and and it sounds good. I'll try to post a video later from my phone. The mufflers did indeed break in in less than 6 months and sound better but a little louder.

 

Didn't say couldn't, just have been told it makes for a noisy sort of long drive.

 

Yes, sorry, I should know better than saying 4speed when talking of the automatics, but that's the way I think of it.

Maybe mind somewhat made up on certain parts, like I'm 99% convinced the Ram Horns 2-1/2" are the way to go. Still not sure if middle dump or rear dump on them.

Undecided on 2-1/4 vs 2-1/2 inch pipe. I know 2-1/2 will undoubtably flow better, just unsure if I will notice. Sound is part of my unknown on this.

Mufflers, I'm still undecided for the most part. I really, really like the sound at idle of the classic chambered pipe, just not sure how loud they will actually be and not 100% convinced I like the popping at high RPMs. Trying to get in touch with the manufacturer to get some more info. This has helped me decide the flowmasters and probably the magnaflows aren't what I want...they are too modern sounding.

I'm somewhat leaning towards buying a kit and finding someone to weld it up for me. My welding skills aren't the prettiest and I don't want mild steel and I likely can't weld the galv/aluminum stuff, definitely not stainless.

I think I need to find some more shops or call some welding friends....

 

No haven't swapped or ordered Ram Horns yet. I have a 2" Ram horn center dump on the right and a 2" truck manifold with rear dump on the left. If they were both the same I'd likely just leave well enough alone as the 2" pipe coming out is mandrel bent I believe and in excellent condition up to the muffler and tail pipe area.
***I take that back, just looked at a pic and they aren't mandrel bent, they are squish bend.

 

If you were closer I'd letcha take the 'Box for a drive to here it...

 

I don't know that you can accurately call them "classic", but yeah, chambered mufflers sound nice at idle, but under acceleration, and especially when coming off the pedal, the sound pretty much sucks IMO. It's alright for a modern pony car, but for classic muscle car or hot rod exhaust, nope, they don't cut it. Might as well stick 21" wheels and rubber band tires on it too then....

 

So you think the factory chambered mufflers that were optional on some 60's GM cars are not classic enough for you? The ones I heard sounded real good.
Walker sold chambered mufflers for years. Had them on a 500 Caddy powered G body .

 

Why are you over them?


Sent from my iPhone using H.A.M.B.

 

I am guessing the low frequency throbbing. My solution, was to add resonators. They cut the annoying sound way down, and they still sound great. The resonaters I used were a straight through design with baffles. They look a lot like the glasspack mufflers I used to buy in the 60s.
Bob

 

......I just think they've been "overused" and the sound can get annoying at times, like a droning. To me they really only still sound good on 5.0 Mustangs.

 

Okay now I am in the same boat looking for freeway friendly mufflers.
My car is a 58’ Chevy wagon 350, 700R. Like my 55 4 door I used almost the exact same exhaust. Brockman mellow tones with 2.25.
They are fine on the 55 car but much louder on this wagon for some reason. After this weekend driving 1200 miles for LSR my boys & I were over it. Over 2100 RPM just loud.
Looking at possibly some dynomax super turbo’s. I do not want the tin can sound so no flow masterish sounds either. I want to keep the price under $150 for the pair. Any suggestions?

 

Guys, look at PYPES new Turbo Pro. A relative copy of Super Turbos but made from st. st. I think they have large case ones now, 18" and that will help tone it down more. If using the Super Turbo, 17747 is number for 20" long ones with 2.25" inlet/outlets and 17749 is the number for long ones with 2.5" inlet/outlet. Both are relatively quiet, both will be almost drone free if you hang the system correctly, and both will make some sound out the back but not be annoying like some chambered ones are.

Chambered ones work great on cars with cats. but tend to resonate a bit more on those without. You can get very large ones and this too will help. Length and volume is what you want.

 

If the same setup works well in your in 55 but not in your 58 you might have some weird resonance problem going on? A H-pipe might eliminate this and bring the noice down.

 

The only thing I can think of is if one was steel packed and set was glass packed. Brockman offers you the difference and he says the steel packed are louder.

 

The exhaust must be longer on the 58 right? Weird things can happen when you play with wavelengths.

 

The mufflers I believe are closer to the engine with it being an x frame car but will double check.

 

I concur. These sound good. I had these mufflers ran as true duals on a '63 289 Falcon. Sounded very good and turned heads.