When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
The primary culprit on the side pipe loss of horsepower isn't the long primary tubes, but the often restrictive side pipe inserts. Dyno's of hooker style side pipes with 1-7/8 primaries and 4" collectors (open pipes no muffler or inserts) are similar / close enough to open headers (usually 6-10 HP loss). For a street driven car, that is negligible. As we try to keep our ears from bleeding, we add inserts to control the sound. I'm not trying to rehash what we all know, but my frustration is how we can't solve the problem of sound and performance with the side pipe. I think we are close, but just not quite there.
I believe if someone made a high performance muffler (like Borla) that would slip on to the end of the Hooker style 4" collector, be long enough, and have turn outs / downs at the end - all the inserts would be obsolete. You could even go up to 4.5" to 5" in outside diameter and still fit next to the car for most cases. The Borla's fit for me, but they weren't long enough to knock down the sound enough. I'm happy with the 3" core on the louvered classic chambered exhaust, but I'd love to find that silver bullet with the side pipe muffler system.
Well, what would you consider an acceptable power loss to get to the sound level you want?
I don’t have anything to do with Classic Chambered other than being a customer, but they really do make a good product. CC doesn’t make any numbers claims themselves, they just talk about improved horsepower with their product. (Probably don’t want to get in a numbers pissing match with people, cuz we all know how much dynos and motor combos can vary the numbers). But, there are customer testimonials where their Vettepacks showed only a 2% power loss over open sidepipes. I’d say that’s pretty good.
Well, what would you consider an acceptable power loss to get to the sound level you want?
I don’t have anything to do with Classic Chambered other than being a customer, but they really do make a good product. CC doesn’t make any numbers claims themselves, they just talk about improved horsepower with their product. (Probably don’t want to get in a numbers pissing match with people, cuz we all know how much dynos and motor combos can vary the numbers). But, there are customer testimonials where their Vettepacks showed only a 2% power loss over open sidepipes. I’d say that’s pretty good.
I'm a CC customer as well, and they make a great product. I too have read the customer testimonials - and Eric at Chambered is who recommended what I am currently running in my side pipes now. I'm not unhappy at all with chambered - in fact I would recommend them to anyone with side pipes! I guess what I'm getting at: I'm curious why no one has tried to move from an insert into the 4" diameter side pipe to creating a complete side pipe muffler that can take full advantage of the larger ID and OD as possible.
I guess there isn't enough demand for side pipe mufflers for Dave Borla to make one for us. I have no idea the amount or research and tooling that needs to go into it. But if he could design replacement muffler, I think it would be accepted.
It looks like there is enough room you could run two Borlas back to back. That might help with the sound.
It looks like there is enough room you could run two Borlas back to back. That might help with the sound.
I've definitely considered that. You are right, there would be enough room to do two Borla's in series.
Originally Posted by SteveG75
Had sidepipes for over 20 years. Small bloc. Big block. There are better flowing exhausts but not better looking ones.
I've reached out to Eric S. at classic chambered exhaust about the idea of a direct fit header muffler for the 4" side mount headers. He's responsive to the idea, we are currently discussing how this would work / look like / effectiveness / construction details etc... At least he didn't say "hell no"... We'll see where it goes from here...
I had a good conversation with Eric at classic chambered exhaust. We talked about increasing the OD in order to increase the ID to around 3.5" or so. It would be a louvered design with a 5" OD (tapered) and fit directly one the collector of the Hooker style side pipe. At this time, the end user would have to add the turn out and hangers. Basically, he could do it - and would if I wanted to. However, the conversation moved into the "why" would you do it. We talked for some time about exhaust flow and sound characteristics. To sum up a 30 minute conversation - to go up any larger in core or pass through sizing we would reach a diminishing return on both required flow and sound control. Generally speaking, if you are running a 3" core it will provide enough flow for anything we generally build. It would also come as a surprise (not really) that the 3.5" + core would be significantly louder even with more OD of packing material.
As discussed before, the classic chambered mufflers provide very little back pressure and customers who have provided feedback to CCE, have quantified that with their own dyno comparisons. From the testimonials I've read, were talking 2% to 5% @ WOT (depending on build) from open headers.
This whole discussion was about aftermarket side mount headers and pipes, not about the OEM side pipes. The OEM pipes have different dimensions and CCE has products for those specifically.
Thanks for following up with CCE! The other big reason to do this as a modular muffler vs. an insert in a pipe is WEIGHT.
For my 3" Doug's inserts (glasspacks), I have an inner perforated pipe, an outer insert shell, the 4" pipe itself, and sometimes a shield. That's up to 4 layers of steel, but the exhaust only sees two of them.
A solution that replaces the pipe with a functional muffler could eliminate one, or even two, layers, half the weight. If it ends up looking goofy, who cares? Form follows function. Put a heat shield over everything, and still come out way ahead on weight.
I have had hooker side pipes with capped and uncapped Spiral baffles. Uncapped are very loud but perform the best. I bought new, SS Hookers recently as im doing a complete restoration. There are some very nice, Ss heat shields you can get for 4" side pipes that look good too. I haven't installed them yet but will eventually to prevent my wife from legs burns.
Run this style side pipe. They look like factory, sound great and nobody ever gets burned.
Don't worry about resale time. There's ALWAYS somebody looking for a Corvette with side pipes.
I agree those are the way to go. They look great, and the single pipe feed into those allows a crossover pipe to be installed to trim down those annoying 8/4 and 5/7 pulses that cause all the noise vs restriction headaches. A shorty header setup feeding those sidepipes should be lighter and quieter at the same horsepower settings, compared to the (overly) long-tube headers. The side covers also open up design options for the internal muffling sections, as aesthetics limitations no longer apply.
Is there a side pipe setup that has, or allows for, open exhaust bypass ? Ideally I'd like very quiet side pipes with a bypass to be able to dial in as much music as wanted.
Also ... how do side exhaust headers handle engine shake ? Seem like unless the engine is sitting on solid engine mounts, engine shake would constantly work to flex the metal in the side exhaust headers.
Is there a side pipe setup that has, or allows for, open exhaust bypass ? Ideally I'd like very quiet side pipes with a bypass to be able to dial in as much music as wanted.
Also ... how do side exhaust headers handle engine shake ? Seem like unless the engine is sitting on solid engine mounts, engine shake would constantly work to flex the metal in the side exhaust headers.
To be clear, I'm only talking about Hooker-style sidepipe headers with side pipes, where 4 individual exhaust pipes pass under the frame on each side, and join in a large collector along the side of the car.
As long as your side pipes clear your rear tires (mine do), you can swap them out in 10 minutes. Perhaps have a second set with different inserts, or no inserts. If you were to drive your car to the track, and then swap them out, you'd need some thick gloves, like the type you use to handle firewood. I don't recall seeing a cutout version with this configuration, as the exhaust would have to go back under the frame at a point at risk for bottoming out on a speed bump. You could do a cutout with a flat NASCAR-style side outlet, though, and perhaps even get it to work with the 69-style covers, though there would be no pipe under there. Inspirational photos at the link at the end.
As an aside, the STS spiral turbo baffles ( https://www.spiralturbobaffles.com/ ) have a center tube that can be capped, or opened, easily for a quick sound change.
There is flex in the sidepipes, but the best solution is to install solid engine mounts. That's the best solution for any C3, really.
There is flex in the sidepipes, but the best solution is to install solid engine mounts. That's the best solution for any C3, really.
I appreciate all the info on inserts. What I'm curious about is use of a bypass after the collector, just ahead of the muffler/insert ... maybe with the use of a parallel pipe to get straight exhaust out the sidepipe exit. I realize that would make it wider ... so just thinking how that might be done.
On solid engine mounts ... is that common ? And how would that benefit any C3 ? Seems like that might transmit a lot more vibration.
Where would everything fit with the bypass at the end of the collector? You wouldn't be able to open your doors, or clear speed bumps, or both. You could do something that rotates to allow more or less air through, like a spice bottle top.
You might think solid mounts make the car vibrate, but they don't. Many on this Forum use them, there are lots of threads on this. They also stiffen up the front end, in a good way. But read some testimonials first.
Great thread and thankful I found it, I have been hesitant to post the exact same question and getting crucified by everyone giving their opinion on "original" and "side pipes".
I have a very original low mile 1980 L48 car in impeccable condition, I have a Borgeson PS kit I ordered and going to install one of these Saturdays when it's not 110 degrees out... I have been thinking about adding a nice Doug's headers and side pipe package while doing the Borgeson, the past 6-7 years I've had 2 Vipers, 2 Cobras, a 64 and 69 corvette all with side pipes, never burnt my leg though my wife has a small snake bite from one of the cobras... I love side pipes.
Ive always loved the look and sound of the chrome header/side pipe package and its been really growing on me on the later C3s when i see them and been thinking of installing them, frankly i would probably also add a set of 15x8.5 torq thrusts to finish the look, of course i would keep all stock wheels, smog, exhaust etc in storage.
I originally considered selling this one because of its condition, it also has a bit of a past and buying something I wouldn't feel guilty about modifying but I love this car and could always bring it back to original.
I do NOT care about value, I have no problem putting more into a car than its worth... there is a value to the enjoyment of the car and I dont buy them for investment.
After reading this thread my mind is made up, I am going to start looking for a header/side pipe package, I was a bit curious about the install and possible issues but not after reading here.
thanks group.
Question for those who installed the Doug's headers, I'm about to order a header/pipe set up, upon recommendations I'm going with ceramic coated... a few questions, first anyone have to modify or dimple for a Borgeson PS, second I'm reading drivers side tends to stick away from the car more than passenger side... anyone experience this?
thanks in advance
08-14-2023, 01:08 PM
They look great, and the single pipe feed into those allows a crossover pipe to be installed to trim down those annoying 8/4 and 5/7 pulses that cause all the noise vs restriction headaches. A shorty header setup feeding those sidepipes should be lighter and quieter at the same horsepower settings, compared to the (overly) long-tube headers. The side covers also open up design options for the internal muffling sections, as aesthetics limitations no longer apply.
