Equal length E\exhaust manifolds

Hey, everyone, I have some questions on making the V12 sound a bit more v12-ish if that makes sense. I have done some research and I realize that there really isn’t any power gains to be made with tubular exhaust manifolds, without custom cams and some other goodies. But that’s not what I am after, I am after a higher-pitched sound like the sound in the video linked below. I know that equal length headers generally help achieve this. I’ll be running this with no emissions stuff to restrict it and probably a valved exhaust that goes into mufflers or dumps out before any mufflers. Just looking for any opinions/knowledge that might be out there. https://www.youtube.com/watch?v=95MhCNKf7CA

By and large that sound is as a result of:
-high rpm;
-a highly tuned (modified) engine;
-likely using tubular headers;
-with not a lot of muffling.

Short of that, you’re not going to get that wailing, hi-pitched scream.

And reaching said revs with wild cans and open pipes will likely exceed the highway speed limit, even in first gear. Screams may well be on the agenda, but are likely to of anguish from jail.

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Well good thing its going to have a 5-speed manual behind it.

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Well, when ya get that sucker built, we’ll want good videos of it!

The Jaguar V12 is more prone to sound like a P51 Mustang than a Ferrari.

Will do! It’ll be a while though.

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Good thing I think the P-51 sounds amazing too :slight_smile:.

Comon guys ? my V12 exhaust , Screams anything past 4500rpm , and turns into a whistle at 6500rpm!

simply run ALL 12 cylinders into a straight thru

. exhaust system with just 1 ONE outlet , at least 5" diamater and 20" or more long! pic, been there for 26yrs !
hard to see the left down pipe 2 1/2" both pipes, large diameter pipes have a much DEEPER tone!
and in any gear that is over 4000rpm on let off it snaps and crackles slowing down, i love it!
Ego says (hey everybody looky me). LOL. you only get one life ENJOY IT!
some of you missed the fact that the left down pipe is much longer than the right pipe, so the exhaust pulses between banks are OVERLAPPED between pulses, above 4500/5000rpm, and the sound for the human ear is almost continous, without any seperations or Staccto blub ,blub,blubby.

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NO Jag V12 will never sound like a P51 engine, maybe top RPM for RR/Merlin is 3000revs?
Jag V12 easy 5000++ rpm, and good Jags will do 7000rpm!
its like Apples and Bananas?? LOL>.


Yeah, I think most everybody missed the fact that the left and right pipes are of very different length.

Did you choose the precise length difference, or did you take whatever it was as this system was cut and fitted to the car?

I really like the idea that the length can be chosen to emphasis overlap - I am sure this makes a BIG difference in exhaust note.

But I never would have made it with a side pipe exhausting on the driver’s side of my convertible- would’ve gone deaf!

It does: by way of example, how 180-degree headers–a bundle of snakes, if there ever was one!–make a V8 sound more like a V6.

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26yrs ago YUP!
my life as usual has always been ahead of the curve, it has sometimes caused my troubles!

when i was young i would do things that everybody says you crazy, that wont work, but they never said anything after it came to reality!
like putting a 1949 Olds Rocket V8 engine into a Crosley roadster in 1954, HA old Shelby thought he was doing the Cobra with a big V8 in 1965! thats 11 yrs later!
the Crosley didnt work out to well it bent the whole car after a couple Dig outs, doors wouldnt close , pry bar gotem closed then couldnt open them!
but the light was lit for American V8s in little roadsters! i was 19yrs old, as usual ahead of whats happening!

a 4 stroke engine like a V8 , fires 4 times in one revolution, a v12 fires 6 times in one rev!
you should hear a 16 cylinders at just 3000revs, the sound for the ear starts a whistling sound ,the ear cannot seperate each exhaust pulse, that begin overlapping sound!
(probably not good for your ears continuosly).
just imagine a V16 at 7000revs?
a little known fact was back in 1960s Ferrari was experimenting with 5L 4 cylinder engines and 5L V12 cyl. engines in F1 cars, they found that 12s were so smooth the drivers were far more relaxed after a long race , 4 cylinder drivers came out of cars disoriented, from constant vibration!

I knew a guy who shoehorned a big Cadillac V8 into a 55 T’bird, and then fitted the pig with six SU side draft carburetors. That’s right, six. Apparently just plumbed everything together on top of the engine with sections of radiator hose. He claims it ran pretty good.

K when did he do that year?
actually the 1950s Cadillac engine is close to the size of a Ford 312 T-bird engine!
and i doubt any one would use a NEW T-bird for conversion?

i think Cunningham did some Chrysler V8s into something?
he went to Le Mans(i think) after 1954/56, and (i think) finished 10th overall, not bad for some 1st arrivals!

Lister was fitting Chevrolets in the 1950s.

Pete , had to be after 1955 1st yr for V8 Chevys!
or did you mean the inline 6 chevy?

OK USA OHV V8s , 1949 Cadillac 331 cu"
1949 Olds Rocket OHV V8 303cu", 1952 324 cu"
1951 Chrysler HEMI V8 331 cu", (to day same basic design used in Top Fuel engines making 10,000hp),
hows that for development tech?
1954 Ford OHV V8 , 292 cu" 1955 312cu".
1955 Pontiac , came on line with there V8 engines
what i’m saying is between 1949 and 1955 the USA auto industry completely advanced with V8 OHV push rod ,2 valve engines. thats just 6yrs ?
so anything done after 1955 was just development engineering of exsisting products!
( ALL these engines mentioned were on the drawing board by 1945/1948, for WW2 Military Tanks?).
almost forgot: the Buick 215cu"// Olds aluminum V8 was slated for light duty trucks and other stuff forget!
to add: that WW2 designed GM aluminum V8, Finally 1951 for the Buick Le Sabre concept car,( any one interested should google it a magnifcient vehicle lightyrs ahead of the world,).
find the site that talks about its available ideas! 1951. seems that WIKIPEDIA has best site!

Technically…1918. :grimacing:

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