great thread guys. I read an article in a magazine that talked about this I'll see if I can't find it. They said it was the firing order that made them sound different.

 

I believe it has a lot to do with the firing order. Think of how distinct a Ferrari sounds, be it V12 or V8. I would love to get my car to sound that way. Also, I do remeber reading a long time ago that the 5.0 Mustang had one of the most pleasing sounds, while a Harley had the worst. From my understanding, Ford put a lot of time and money into making the 4.6 sound similar to the 5.0, and it does, but it sounds a bit "hollower" for lack of a better word. Too bad they didn't put more money into power development, or there would have been less 15 second cars at Commerce this past weekend! lol

 

here's a sound clip of my stock-internal LT1 with duals and x-pipe. When I fired it up for the first time, it sounded more like a 5.0 stang than a SBC to me... It's mellowed out with a little runtime and sounds like a cross between the two now.

http://www.lt1.org/other/roadieLT1.wav

I was in a 45 mph zone, so I made a turn on only ran through first and half of second. This sound clip doesn't do the exhaust justice (like he said above)

 

LT1's and older SBC have the SAME firing order as older Ford SB's. Thier cylinder numbering conventions are different.

SBC: 1-8-4-3-6-5-7-2
driver side cylinders are 1,3,5,7
passenger side cylinders are 2,4,6,8

Old Ford SB: 1-5-4-2-6-3-7-8
driver side cylinders are 5,6,7,8
passenger side cylinders are 1,2,3,4

If you re-number the Ford cylinders, like the SBC, you end up with a firing order of: 2-1-8-4-3-6-5-7, which is the same as 1-8-4-3-6-5-7-2



LS1's and newer Ford V8's have the same firing order.

LS1: 1-8-7-2-6-5-4-3

5.0/4.6: 1-3-7-2-6-5-4-8

Re-numbered using GM cylinder convention, and the 5.0/4.6 becomes 2-6-5-4-3-1-8-7, which is the same as 1-8-7-2-6-5-4-3.

For all intents and purposes, the old firing order is the same as the new, just flipped, from front to rear. However, this reduces the amount of "wind-up", that the front of the crankshaft experiences. Think of the crankshaft as a torsion bar, rigedly mounted to the flywheel/transmission. The four crank throws need to transmit thier torque along this torsion bar back to the flywheel. Assume each crank throw applies the same torque to the torsion bar (crankshaft), and you will realize that the front throw (cylinders 1,2) has the longest torsion bar length, and will twist the most. The rear throw (cylinders 7,8) have the shortest torsion bar length. During the LT1's firing order, the 2-1 "punch" of the power strokes wind-up the front of the crank, then unwinds. The LSI does not have the 2-1 "punch" at the front of the crankshaft, instead, it has an 8-7 "punch". This is next to the flywheel, and causes virtually no wind-up.

Most engines have thier accessories and computer sensors mounted off of the front of the crank, so reducing crankshaft wind-up can reduce overall vibration and ignition timing and cam position instabilities.

So the question is, who actually came up with this firing order FIRST? Was it Ford with the 5.0? Did GM, Chrysler, or anyone else use this firing order on an older engine?

 

My friend has a LS1 with duals and I also have a couple of friends with Mustangs, havnt been able to convert them yet, but my buddies LS1 sounds a lot like a Mustang. I heard that LT1 vid and it soulds more like a deaper 5.0 then the LS1.

Did a search and every engine out of Detroit had the same firing order except the non HO 5.0 motors had a this firing order:
1-5-4-2-6-3-7-8

 

i think im going tohave to agree with the firing order, cause a v6 mustang also has that same sound.

 

No way! If a V6 sounds the same, then why doesn't a Chev V8 sound the same?! (which is at least the same size and number of cylinders?? ). A V6 can't share the same firing order as a V8...............it's impossible! I'm still going back to the theory of MATERIALS, and cylinder and port shapes as well, because Ford probably has a design that is carried throughout many of their engines V6 / V8, that will have an effect.

 

a mustang sounds like it does because of the roller cam, think about it. Ever heard a chevy roller cam, it has the same tone!

 

Come on guys, now were getting a little too funny with the guesses V6s sound the same? Roller cams are responsible?....

 

A V-6 with good exhaust does sound the same. I got in a race with a V-6 the other day that I thought was a cobra, with duals and the way it sounded. Then I asked him why he got romped so bad at the next light. And he informed me I had two more cylinders than he did.

 

I have yet to hear a v6 sound anything like a v8. V8 has a combusion event every 90* whereas a V6 has a combustion event every 120* That's why as a general rule of the thumb, the more cylinders you have the less time between combustion events, and the smoother the engine sounds (Ever hear a V12 Ferrari?)

My point of confusion is this. The 4.6L sounds almost the same as the 5.0L. They are dramatically different engines, OHV vs DOHC and they are also made out of two entirely different materials Al and Cast Iron. The 4.6L is a square engine, however the 5.0L is an oversquare engine. The only things similar are they are roughly the same size, have the same firing order and have very close rod/stroke ratios.

4.6L:
3.552 Bore
3.543 Stroke
5.933 Rod Length
1.6746 Rod/Stroke Ratio


5.0L:
4.000 Bore
3.000 Stroke
5.150 Rod Length
1.7167 Rod/Stroke Ratio

They do, however have the same style of exhaust, true dual.

Because of that, I have a feeling that the Exhaust design plays a much bigger role than the materials, camshaft, and internal engine differences such as bore/stroke, etc...

One other thing. a 350 with a 5.7" rod and 3.48" stroke has a R/S ratio of 1.63. Can anyone confirm if the 327 sounds any different than the 350? This may help put the R/S issue to rest, as the 327 has a R/S ratio of 1.75.

 

I always thought that the 5.0 sounded like it did bcuz of the design of the combustion chanber, atleast that was what someone told me.

The whole exhaust doesnt sound right. Have you ever heard a 302 vs a 351W? The 351W has a much higher pitch and doesnt sound anything like the 302, or am I wrong on this?

 

well-
I didn't take any acustics classes yet, nor did I read this whole thread- but i have done some reading here and there.


I do believe it has to do with the intake/exhuast valve sizes. I'm not sure how it all plays in, but i know thats why harleys sound the way they do. they actually copywrited their sound! From what i read somewhere, either ford or harly tried to use bigger valves and keep the sound...
never succeeded.

Also, it does seem like stang sounds a bit like a muffled harly no? a stretch, but it seems like if u put a harly in a car muffler- it would sound SIMILAR to a stang...

 

A V Twin is considered sort of a cousin to the V8. Harleys have flat fire cranks, and they are not an "even fire" engine.

 

i know squat about bikes except that I want one, and I want a GSXR
i just happened to read something somewhere along the lines that their sound along with the stang is due to the valve sizes, chamber and some other stuff i didn't care to really note at the time...