Side vs. Straight pipes

[fzabski]

I am looking for pro's and con's of both. I would image that the side pipes are louder look nicer then the straight pipes. The side pipes are classic no question. Is there exhaust smell issues to deal with?

If you get a street 427 (ERA) can you retrofit the side pipes later?

Understand it's personal preference. I am not going to be racing my car (when I get it). I want to be able to drive it and not get my %$lls broken. Is this an issue.

I am sure many have had the same question

Thanks in advance.

[Lloyd GT40]

Side pipes are definately loud. I enjoy the sound. Only problem is on long trips it can get a bit too much. Just don't gear the rear to low and go with a five speed. At 65 mph it's not that bad in fifth gear. Then again there is always ear plugs. About changing over to under/rear exhaust what are you going to do with the fender openings where the exhaust use to exit with a painted car?


LLoyd

[fzabski]

Lloyd:

My question was if I got the street version (without the wholes) for the side pipes and then wanted to put the side pipes on would that be possible/feasable?

[Lloyd GT40]

Gotta it. Sorry had it backwards. The only concern in changing would be the cut in the painted body would be a clean cut and would it damage the paint? I know i spent a alot of time sanding to get a clean symetrical opening on a bare body. I think i would do a little more research look and listen to both. I think your going to have a tough time finding cobras with under the car systems. Very scarce. The under system is a little too tame for me. I've heard pro and cons for both.
Good luck

LLoyd

[Mike Braatz]

I've not experenced any smell or fumes from the side pipes. I have side pipes and they are annoying on long trips, but as suggested earlier ear plugs work wonders, and they sound great around town.
Your choice--I'm not sorry about mine
Mike

[Dwight]

I think I have the loudest pipes in town and love it. I wanted to go with under the car pipes when I was planning my car but did not think I could get a exhaust system under a car that was so low to the ground. Now that I have my car up and run, I think the best is side pipes. BUT each to his own!!!!!! Maybe my next Cobra will have under the car exhaust system.

[Aussie Mike]

A Cobra with sidepipes is difficult to register down here. Most cars start out with an underbody exhaust and then the side pipes go on after the car has been succesfully registered.

I was at the Robnell factory a few months back and saw how they get around the exhaust opening issue. They cut the holes for the side pipes but have a neat little panel that flush fits in the hole. The panel is painted along with the rest of the body work and then if the owner wants to put the side pipes on later the panel can be removed. You should talk to the guys at ERA and see if they can supply something similar with your kit.

Cheers

[Bob Putnam]

The previous replies have been accurate. We can cut the hole anytime, and a cover should be no problem.

The undercar exhaust is much quieter to the ear - what (reduced) noise there is goes to the rear. The drawback is some horsepower loss, and the exhaust is very tight to the chassis, making it tedious to position it exactly right.

[a427sc]

Undercar exhaust also adds significant heat to the foot boxes. The added backpressure from restrictive header pipes, smaller mufflers and long convoluted tailpipes precludes most performance mods to the motor as it just cannot breath.

Now if you want to get fancy and $ is no object, have a custom set of tri-Y headers made, stainless of course to withstand the heat, with the 2 secondary pipes bending under the car side by side, joining under the foot box. You can use oval pipe ala NASCAR, and performance oval inlet mufflers. The tail pipes will be a chore, fabricating all the bends in oval tubing, and there is the interference problem with large rear tires.

I still have the old style ERA undercar exhaust system hanging in the garage rafters. I bet 4 or 5 cars went through CT inspection with it before they allowed sidepipes (with heat shields).

Of course, other brand kits may have more space....

Don

[cliff1963]

If you are debating the sidepipes vs. undercar, go with undercar exhaust. I built mine with sidepipes due to peer pressure and hated it from day one. It is nothing for me to drive 400 miles at a time. In traffic with the top up, you will get fumes in the car trapped by the roof. I changed mine to 3" stainless pipe all the way out to the rear, no heat from backpressure, just a nice ride. It is still loud, but it is mostly behind you. I also did not experience any power loss. Go with your instinct!! and enjoy the ride!!!

[petek]

Go with side pipes a little shorter than normal and build up two sets of tips. First set- normal side pipe outlets. Second set- pipe that curves back under the car, over the rear end, and then out the back (side pipes with rear exhaust).

[Jack21]

Au contraire m'seur,

There is little room for an undercar exhaust on a cobra.

But, sidepipes are not inherently noisy or smelly.

If your carb is running too rich, you'll get exhaust fumes. If the car is moving forward, there is no odor, nor does any exhaust get trapped in the car, even with top and sidecurtains installed during winter driving.

And the pipes are loud only if you make them so. With decent glasspacks, you can get a deafening roar, a mellow rumble, or a throaty purr. Have a summer pair, and a winter and trip pair.

Have a pair of Page 30" x 2 1/2" (mellow rumble), and 36" x 2 1/4" (throaty purr). Mufflers are about $30 each.

[cheesepocket]

The other choice is a hybrid of the two, using headers that exit under the car, positioned appropriately for mufflers to bolt right up, and then the exit in front of the rear wheels, sort of Nascar style. You get your choice of mufflers then, and don't have to worry about getting the exit all the way to the back of the car. The 3" flowmasters with the lumpy cam sound unbelievable. There is a pic at ERA's website, I think Bob there called them "interesting".

[MRITTER]

Or you can bolt a turbo to each side and enjoy the performance enhancement. They really help subdue the sound.

Of course you get it back under full throttle, when the wastegates open, which is perfect.

Later,

Mike

[Tom Wells]

Here's a couple of "under the skin" shots of my E-M's undercar exhaust:

http://www.clubcobra.com/photopost/d...hassisLeft.jpg
<P><P>
http://www.clubcobra.com/photopost/d...13ExhPass2.jpg
<P><P>
Hope this helps,

Tom

[Ron61]

I live in Northern Califoirnia and all of the above answers are correct. I have side pipes and they are noisy but I built my car to race and then got to old. The major drawback I have seen on under car pipes is there were three Cobras and I can't say for sure what make but I think it was Excalibur that burned to the ground. They had under car pipes and catylic convertors and they just set the fiberglass on fire so if you go with under car pipes be sure to put some kind of heat shielding on the bottom of the body the whole length of the pipes for extra safety. I like the sound of side pipes versus under car pipes but I am not taking sides as that like everything else is a personal preference of the person building the car. Enjoy the car and build it to suite you and not everyone else.

Ron61

[Todd Hedges]

I just put the first 400 miles on my ERA with a bb 428 & side pipes.

YES the noise does take a little to get used to, especially in the higher RPMS. It is beautiful.

Nothing, I repeat, NOTHING will scare the crap out of someone
who is unfamilar with this type of car, like a big block with
sidepipes running at 5500rpms and closing in on 6,000.

I will say if I was going to build another car, I would put the
undercar exhaust for those longer rides and the neighbors sake.
The sound at 3,000rps for over 1 hours does take its toll.

Eitherway you can't go wrong.
Have fun.

[flipper35]

I made two 600 mile round trips to Oceanside and the wind noise was far worse than my engine turning 2200rpm at 75mph and no, these are not like the Contemporary reverse flow pipes, they are glass packs open and free. I like the sound of the sidepipes at full song, but no-one likes getting burned on them. Look at both and listen to both. Pick the one you like. It would be a great project either way. I bought mine for Dad and I to do together. When it was done, everyone assumed it was his and I just let them.

Brent

[Chaplin]

Can you guys answer a couple of questions for me. I have never had a car with side pipes and am unfamilar with them. Truth be told, until reading this thread I always thought they were merely hollow tubes with some baffling inside. Am I corret in understanding that there are different inserts that you can put into the side pipes to change the decibel level? Although I love the sound and the look of the side pipes, I do not want to become deaf on long trips-- is there a particular insert that will make them quieter?

Also, I love the sound of the Flowmaster mufflers. Does anyone have a setup similar to Tom Wells E-M on a Unique?

Thanks for the help.
Mike

[Fred Douglass]

Good thread!

Let's say I bought an SPF ("a SPF"?) and I had enuff moolah to bribe my insurance company to roadify the car, would it be possible to fabricate a set of undercar pipes AS WELL AS a set of side pipes? Or would the changing-point (I assume it would be somewhere downstream of the exhaust header) be too complex and unworkable? It would, no doubt, be heinously expensive. Believe it or not, this was the route many SCCA-racers went when taking their Corvettes, etc. to
The Glen or Limerock. Bob Putnam and others sound encouraging, but is it workable?

I like the idea of an under-car system, especially if one were to take his wife, girlfriend or dog (or any two of the previous except #1 and #2) touring---My inclination would be to go with the side-pipes and ear-plugs. However in the people's Republic of Taxachusetts, ear-plugs and other impediments to hearing (such as disc-players, etc.) will get you a direct trip to a re-education camp.