Jack-TX

I am just about done with my 1966 427/390 4-spd numbers matching convertible. As excited as I am, the only thing the car doesn't have (and didn't from the factory) that I really wish it did is side exhaust. So my question is this: How adversely would I be affecting the long-term value of the car by converting it over to factory side pipes? It has a perfect rear-exhaust on it now, and really there is no reason to change it other than my own personal preference. But preference aside, do you think it will hurt the value if it is done to factory correctness?

fsc66

One thing that may help you make up your mind easily is, is your car a St. Louis or AO Smith Car?

Paul

Nowhere Man

is it a A.O Smith Body or St Louis built body per the trim tag? Have you ever rode in a BB with side pipes?

65GGvert

No doubt it would hurt the value if it is an AO Smith car. I have had many side pipe cars and like the look and sound (sometimes), but it's such a pleasure to drive with a stock exhaust that I don't wish to have it anymore.

bb62

There are two ways to look at side pipes - "value" and "is it what I want". There are pros and cons to both:

Value: - If you install original GM side pipes, it would not hurt the value of the car because you can recoup the cost of restoring to the original configuration by selling the side pipes - again, if they are original GM pipes. Anything less then that will hurt the value of the car (unless your car is not an NCRS type candidate in which case you may get extra value).

Is it what you want:
- Power - Original side pipes will hurt the power output at the wheels - especially for big blocks (but mostly at higher RPMs). If power is your desire, the "off-road" under the car pipes are better. Now some will say that you can buy set-ups that won't lose as much, but you still have to contend with the multiple bends that disrupt the laminar flow of the exhaust and many of those exhausts can be significantly louder than stock.
- Sound - There will be lots of disagreement on this but it is really personal preference. Some love the aggressive sound, others think they are too loud. Some like them for short drives only which is how they use their cars. You will find a lot of people who say they drone on and that a 2 or more hour drive will convince you not to buy them Still, others don't mind the extended noise. I have heard many people say that they prefer the sound of the off-road exhaust in big blocks - it tends to be more mellow, more menacing.
- Looks - Again a personal preference but my personal view is that they disrupt the lines of coupes (by making them look too tall - per one Corvette chief designer). On convertibles they create a different look of aggression that many like.

Good luck with your decision.

Revfan

Another route you can go is off-road - N-11 exhaust . Still under car, but you get more thunder.

MikeM

I put factory sidepipes on my '65 in the early '70's. They were rare back then and I thought I liked the looks. Fast forward to today, I wish I hadn't done it. I think it takes away from the basic lines of the car and besides, lot's of midyears now have side pipes so you can look like everyone else.

One cost penalty will be the $2000 or so it takes to put the pipes on along with the rear panel you'll have to buy and paint. Might be more than that.

Many that don't have the factory GM side pipes complain about excessive noise.

SonnyAK

I have a '66 L72 car that didn't originally have sidepipes but a previous owner had them installed. My personal preference is to have them and if my car didn't already, then I would certainly add them. I really don't care about the value since I don't plan on selling the car, but I don't feel that it hurts the value much since anything (most anything) can be taken back to original.
It's certainly a personal decision that you'll have to make and live with - either way, be sure to do whatever will make you the happiest!!

68hemi

I agree with Mike on this. I had them in the early 80s on my 66 BB and on my 66 SB as late as 2007. When you are used to looking at the profile of a C2 without them the cars WITH them start to look like a big belly bass.
There are other things to consider as well. If you like power as most BB owners do they reduce your power compared to the stock under body system as the inside of the pipes are only about 1 5/8" exhaust flow path.
If you like to listen to your radio or have a conversation on the highway, forget it. The pipe outlet is right at your ear and even with the windows up it is droning after about 15 minutes on the highway.

Frankie the Fink

I agree with MikeM as well - if your car is that original I wouldn't do it...
The novelty wears off pretty quickly in the sidepipe cars I've been, that drone can work on you after a long drive...
Just my opinion...

MikeM

Well, mine doesn't have an objectionable noise level, drone or whatever you want to call it. That's because of the factory, GM pipes and the fact that I have an engine with a standard camshaft. It's my understanding all the aftermarket pipes are noisier. I don't know. Don't have them but I've heard some that are very loud.. At steady cruise, without accelerating, it's pretty quiet even with the window down. Now, if you goose it...............................

bbxlr8

This sums it up for me as well - do what YOU like!

They were already added to my L79 conv, but I really like the look and the sound. It does get old on the highway and I have to go to earplugs (not the greatest solution & is rarer for me - drive a lot but mostly local).

I also get the aesthetic of the original pure design side of the equation as well.

dahogan

Similar facts for me as well except mine is a L79.

Wayne88

As far as value; I would change to side pipes and keep the current exhaust and rear panels, then include them with any future sale of the car. So where would the value loss be?

Frankie the Fink

I'll defer to you on that then -- its been 4 decades since I've ridden in one with the "lake" pipes...

MikeM

Kickstands they were called here.

I would guess that most here do not have GM pipes.

GTOguy

Not to sidepipe would be my choice. I think it takes away from the clean lines of these cars, and the exhaust going through the valence of a non-sidepipe care is a classic look. If the car came that way from the factory, I would be ok with it....but if a car had added sidepipes, I would look for another car that didn't have them.

Frankie the Fink

I don't know if a '67 has the "hangers" for the rocker molding like a 63 but if so, bend them up out of the way - don't saw them off !!

856666

There is nothing that puts a smile on your face like the rumble of a side pipe BB from cold start.

Do it and reverse it later if you want to.

Phil

Nowhere Man

dad has NOS pipes from the mid 80’s on his L79 coupe. The car sounds great around town. Anything more then that it’s border line annoying.