T/A and AAR Side Exhaust...Why???

So the T/A and AAR cars had side exit exhaust, along with other TransAm cars of the day.

Stupid question... why?

It was my understanding that it was a racecar styling cue. Kind of like the race cars used on the track or at least how people perceived them to be.

Others may have better ideas.

I am pretty sure that the higher rear end stance on the AAR & T/A was to give the exhaust tips ground clearance. Looking forward to what others say.

Racecars of that day all had side exhaust.

BTW, no other pony cars made for Trans Am homologation offered side exhaust.

I thought the Javelin T/A has side exhaust as well. Maybe they has "laker pipes".

No lakes pipes. Out the butt like most. https://www.bing.com/search?q=amc+javelin+trans+am

These "Sidewinder" exhausts were an over the counter performance part.

"NO AMX OR JAVELIN LEFT KENOSHA "FACTORY" WITH THESE INSTALLED, PERIOD."

http://www.planethoustonamx.com/main/amc_trendsetter_pipes.htm

Possibly SCCA Racing Homologation? Same as NASCAR, NHRA, etc.,

Same with the fiberglass hoods and big hood scoops or air induction. "Win on Sunday, Sell on Monday"

The side exhaust was part of the pre production styling exercise that made it to the production car, it had nothing to do with homologation.

The almost rest of the story is in the link


AAR Cuda Info & History

Marketing

But if it was only a styling and marketing exercise and not a performance exhaust design why did almost all of the Trans-Am series Cuda's and Challenger's use that type of exhaust exit? Always thought in racing especially it should be "Form follows Function"?

T/A and 67 GTX in my opinion were the 2 best looking exhaust on the planet. The 71 3rd.

TA race cars and many others in different classes had exhausts that exited out the side, long before Chrysler did the AAR and T/A.
One of the reasons is packaging the exhaust on a car that's low and often with a large fuel cell.
Many if not most of the TA racecars had tunnels to fit the exhaust; a couple of them that I worked on sure did, all the way into & through the rocker panels.
AMC tried to homologate a hood scoop before Chrysler, but SCCA nixed it - it's interesting that they were allowed for the AAR & T/A, but never re-appeared on Javelins.
Taking in fresh air was accomplished within SCCA rules by ducting it from the radiator support, or for some cars, cowl-induction hoods.

The side-exit exhaust for the street cars was a victory for Marketing; fairly amazing considering Chrysler budget constraints.

If you haven't checked out a Vintage TransAm race, you've really missed seeing some of the coolest cars on the planet.
It's easy to Google photos of the cars & see the on-track schedule.
Here's the Javelin I helped restore & crew...ex-Penske & Roy Woods...

NICE WORK

Me thinks it's also performance, weight savings and maybe racing homologation. Even NASCAR knows that not having to make all of those bends to get around and over the rear axle is better for performance. Also there's a considerable weight savings by the shorter exhaust tubing and hanger hardware.

For what ever it is worth, the exhaust systems on the real race cars looked nothing like the exhaust on the AAR or TA cars.

The real race cars ran the exhaust through headers (at least at some places), collectors or head pipes, then the exit pipes with the 45 degree bends to dump in front of the rear tires.
The AAR & TA cars ran through specific exhaust manifolds, through head pipes into mufflers with the inlet pipes next to the exit pipes. The exit pipes came forward out of the mufflers to the outside f the muffler inlet pipes and made the 145 degree (or so) bends to exit just in front of the rear tires. Those exit pipes were hard to find, hard to install, and didn't last very long. The gas station I worked at in the early 70s had a customer that bought a new TA when they became available (his was the only TA sold at our local Dodge dealer). The car was an expensive toy he could not afford, he didn't have it very many years, then we never saw it again.

I had a friend that bought an original body in white AAR Cuda with the basic cage in it. He never did get it built, but always talked about it (I saw it and its certification tag in his storage building). Years later I saw an ad about a guy needing to sell a partially restored AAR. He needed to get cash fast for it. I knew my friend had the cash on hand (it would have taken me a week to get the money). I stopped by his house, handed him the ad and told him he needed to buy this car then left. 2 days later the car was driven to his house, and I was there and got the first ride after the cash exchanged hands. My friend enjoyed that car for several years before he sold his Mopar collection just before his death.

I had heard at one time that side exit exhaust is mandated in many racing classes because rear exit exhaust causes the rear of 2 cars to overheat. All that heated exhaust pointed directly into the radiator of the 2nd car gave the lead car an advantage.

If you can't draft, you can't pass, if you can't pass, then racing becomes boring and nobody watches it.

Sounds logical to me especially when you look at that AAR above spewing flames.


Man those are some sexy cars above. All of them even the Furds & Chebbies.
Race cars today look so bland and undistinguishable. Save for some F1 stuff.

A12 - Thanks, that car was quite an effort; found a lot of tricks in it - much more than the privateer cars I've worked on - and it's one of the best-sounding cars I've ever been in.
I could tell several fun stories - and a couple of wrestles - about that deal.

IMGTX & Poorboy - it's NASCAR that prohibits rear-exit exhaust for the drafting/overheating. But side-exit is still a packaging issue, plus length factors in.
Bear in mind that most exhaust pipes are at least 3" diameter, up to 4". That's why they're tunneled.

that doesn't work for me.
IMO. the big downside not yet mentioned, it killed an optimum ride height, and that is a killer even on a street driven TA type car.

My memory is side exhaust was the norm until late 60's David Pearson I believe with the Wood Brothers?, first ran the exhaust straight out the back. Not sure they disclosed why exactly they did it, but David won and nobody could draft him for long for reasons stated above, and Nascar quickly nixed that solution. I thought it was first done at Daytona, but I am not sure.

Side exhausts are used in road racing, primarily for safety during refueling at a pit stop. It keeps the exhaust exits away from the fuel cell and the fuel filler located at the rear of the car. I copied the T/A AAR exhaust routing with mufflers for my Mustang, now made street legal after many years as race-only.

nicely done mustang !
if i may ask, on the jack locator on the rear end housing, what is the cotter pin's purpose, and the square item [retained by the cotter pin perhaps ?] in the center of the locator used for ?
as to side exhaust, when they came out, my brother and i did that on everything from darts to 4dr imperials, as well as everything in between, because it was cheaper to do than buying tail pipes.

Looks like a drain plug.

Yup, likely a combination drain plug & jacking point.
Plug pinned to prevent unwanted loosening.

You have a very nice car, and this your second post, so I will be very gentle, but I disagree.

In road racing, an analog tracking device for high speed off track excursions?

Yes, that’s it.

Thanks, it’s been a 28 year journey with this car, and loads of fun.

I’m curious to hear your thoughts as to why you disagree. Below is a photo of a hot pit refueling of the Sunoco Camaro that drove the point home -for me anyway. Several early Ferraris with rear exit exhausts had a protective horizontal flange of sheet metal over the pipes exit to prevent refueling spills from hitting the exhaust tips directly.

Since you asked, our biggest difference here centers around your use of "primarily". My first counterpoint is if safety indeed was a motivation, the lack of any fire suit, goggles, gloves, no socks, and the amount of gas regularly spilled in pit stops, safety seemed to be of minor concern in the big picture IMO, and there are a number of other advantages side exhaust provide that would go more toward winning races, which again IMO was the "primary" concern. I suspect that pavement wetness pictured might be from spilled fuel as is the feeble attempt at the use of safety dri? Although there is a crew barely shown with a water? hose aimed at the refueler just in case. Speaking of old pictures, my favorite related fueling pic is at Sebring with a Ferrari team using a very large galvanized wide open top funnel to dump fuel in in the trunk area for a refueling pit stop

BTW, is that Roger Penske at the RF kneeling?

Yup, that's Roger - he typically released his cars in that era.
That fueling hose may be attached to the huge gravity-fed rig they ran that year, which IIRC, SCCA eventually banned.
Filled the car VERY quickly...but could make a mess...

It looks like a typical semi gas tanker hose set-up.
Typical Roger.

never gave that a thought ! thanks for pointing that out guys ! you learned an old guy something, now if i can just put it somewhere i can remember it.......

I’ve always admired Roger Penske and his outside of the box thinking. His team chilled the fuel in that big gravity rig you described using dry ice to make it more dense, and blew it through that ginormous hose into the cell in a matter of seconds. I believe they were filling a 24 gallon cell in just a few seconds. In addition to speed of refueling, they were able to pack a few percent more fuel into the cell when compared to others fueling up at ambient summer temps. I read Mark Donohue’s book “Unfair Advantage” many years ago. And I recall he touched on this refueling topic in it. It’s a great read.

Yes, that plug and Jack point combo allows you to drain all the oil out of a 9” rear without removing the pumpkin, while also giving some protection for that low hanging plug And in road racing, I’m changing it every couple of events. I believe there a lot of opportunity for “cross pollinating” of ideas between road race and my newfound interest in big Mopar stuff and vice versa.

I personally have a tough time accepting the loss of 1" of sacred hard earned ground clearance with something likely rather adept at catching on something all for the convenience of a jack point.

Dude, if the center of the pumpkin can hit the ground, you have way bigger problems !

Valid concern on a rock crawler or off-road rig, non-issue on a pavement car.

So we agree, no need for the drain plug protector aspect?
BTW, have you ever left the track at say 100mph only partially under control in a lowered car with some DF, for any number of reasons?

I've done it a few times on a rr motorcycle on the race track at over 120mph and once in the rain at over 100mph if that counts

I know it was factory and one of the things that makes these cars unique. I personally have never been a fan of the look. Just looks cheap to me and outcof place.

Um, no, JCC, we don't agree, and you misinterpreted my statement.
And you don't want to compare/measure racing experience with me...I'll just leave it at that.

I think this is all getting way to technical.

the time frame of the design was the late 1960s with the production schedule in 1970.
The side exhaust exit really only needed to look cool and be different, to become reality. If the car company could attach a racing excuse to the cool new thing, it sold better.

Basically because Chrysler was more bitchin than Ford, Chevy or AMC.

"misinterpret." how?

Is that car one of the Hurst prep rental prep Shelby 350 GT cars sold by the rental company to the public the next year after they came out?
I was offer one by one of the Hurst rental agents in the San Franscico airport in 1967 while I was in the Army and of course I couldn't afford it, let alone make arrangements for financing it

Cab, no my mustang was not a hertz car. It was a former street car prepared by a guy in upstate NY for road racing around 1970-71. It led a hard life, passing through a number of hands before I bought it. The car Raced at Mosport and Watkins Glen in the early 1970’s in both A/S and B/P. I pulled it out of a North Carolina junkyard in 1996 and rebuilt it in my garage in CT. I got it back on the track in 2000 following 4 years of work. . My middle son now has it in TX… and it will be staying in the family. That car went out, and a RB 496 ‘Cuda came in.

My dad rented a Hertz GT-350 while on a business trip in period. He told me it drove like a truck, but a very fast truck. The fast ratio steering box was/is a muscle builder.