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ive been trying to find videos on the different extractor sounds iam curious to hear what a 6-2-1 set of extractors sound like witha a 2.5 in system compared to a 6-3-1 extractor set up

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3 hours ago, slydog said:

They sound no different. Only way to make a exhaust sound good is to put a stout engine on it.

i was hoping you'd find this thread, because i was going to post similar.. extractors haven't made any sound difference i've noticed before

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7 hours ago, deankdx said:

i was hoping you'd find this thread, because i was going to post similar.. extractors haven't made any sound difference i've noticed before

 

And a 2.5" is not big enough. The old twin 2.5" on mine was stupid added weight but worked well,however a single 3.5" would of done the same with half the weight. If a exhaust sounds like poo it's cos there's not enough engine in front of it.

 

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2 hours ago, slydog said:

 

And a 2.5" is not big enough. The old twin 2.5" on mine was stupid added weight but worked well,however a single 3.5" would of done the same with half the weight. If a exhaust sounds like poo it's cos there's not enough engine in front of it.

 

i would have thought that all depends on how many revs it's going to do. 2.5" surely would be fine for 5500rpm for eg on a 4 litre ish? probably higher revs  even

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I've had both, but in my opinion, 6-3-1 sounds more sporty as the pulses are separated for longer before joining. The pipes are grouped very differently between the two types.

With the 6-3-1, numbers 1 & 6, 2 & 5, 3 & 4 are paired respectively, so if you observe the inline 6 firing order, each pair is 360 crank degrees apart from each other. This gives maximum scavenging and does it more evenly. Each opposite pulse helps scavenge its paired cylinder.

With the 6-2-1, there are 2 groups of 3 cylinders with 240 crank degrees between them, and each exhaust pulse from one cylinder sees two scavenge pulses from the other two at 240 and 480 degrees. Depending on the tuned length, there could theoretically be two optimum rpm points where the scavenging effect is ideal, but grouping 3 cylinders together might result in a bit of overlap and work against that effect when compared to the 6-3-1 design.

Regarding sound, there is only a subtle difference and hardly worth worrying about, but my dad's XF had the first set I'd heard and I still remember how it sounds, 25 years later. I think the 6-3-1 is better at higher rpm and you can hear the engine come "on-song" more compared to a 6-2-1 header.

Sure, you can lengthen the secondaries on the 6-2-1s to dial them in, and folks on here have had great success using this method, but to just go and bolt on a set and drive away, 6-3-1s are the go.

Really, the only arguments against going with 6-3-1s is clearance, and extra cost. I seem to remember Pacemakers only having about $40 price difference, going back a bit though.

The biggest factor in exhaust sound is always the muffler. If you choose to go with a chambered type on a 6, you'll need to run a resonator or two with it, otherwise it will drone like a bitch. I have had better success with a straight-through type glasspack which gave a nice presence but was quiet on the open road. 6-2-1 headers, 2.5 system, resonator (basically a hotdog without the packing) and an offset glasspack (side in, centre out). That was on my Cortina and was a great system.

Conversely, when I bought my XE wagon, it was a 6 and had 6-2-1 headers, 2.25 pipes and a turbo-style muffler with a hotdog at the rear. It droned like a mofo, right at the 2100rpm mark where crossies often do. The V8 I put in was quieter.

Don't be fooled by people telling you the pipe size is too big. Any back pressure is bad. People who say that an engine needs back-pressure to run nicely are probably comparing that to open headers, which often don't perform as well as headers with a tuned pipe/collector fitted. That's a pulse tuning issue, not back-pressure.

Smaller pipes are louder. Go as big as you can squeeze in there, and it will cruise sweet but give some bark when you mash it. Small pipes drone and resonate badly.

Sent from my CPH1920 using Tapatalk

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i would have thought that all depends on how many revs it's going to do. 2.5" surely would be fine for 5500rpm for eg on a 4 litre ish? probably higher revs  even
Pipe size should be calculated on engine horsepower, not displacement. 2.5" is ok for 200hp, but you need to add an extra half inch for every additional 100hp. So a mega-stout crossy making 300hp should have a minimum of a 3" single system.

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8 minutes ago, gerg said:

I've had both, but in my opinion, 6-3-1 sounds more sporty as the pulses are separated for longer before joining. The pipes are grouped very differently between the two types.

With the 6-3-1, numbers 1 & 6, 2 & 5, 3 & 4 are paired respectively, so if you observe the inline 6 firing order, each pair is 360 crank degrees apart from each other. This gives maximum scavenging and does it more evenly. Each opposite pulse helps scavenge its paired cylinder.

With the 6-2-1, there are 2 groups of 3 cylinders with 240 crank degrees between them, and each exhaust pulse from one cylinder sees two scavenge pulses from the other two at 240 and 480 degrees. Depending on the tuned length, there could theoretically be two optimum rpm points where the scavenging effect is ideal, but grouping 3 cylinders together might result in a bit of overlap and work against that effect when compared to the 6-3-1 design.

Regarding sound, there is only a subtle difference and hardly worth worrying about, but my dad's XF had the first set I'd heard and I still remember how it sounds, 25 years later. I think the 6-3-1 is better at higher rpm and you can hear the engine come "on-song" more compared to a 6-2-1 header.

Sure, you can lengthen the secondaries on the 6-2-1s to dial them in, and folks on here have had great success using this method, but to just go and bolt on a set and drive away, 6-3-1s are the go.

Really, the only arguments against going with 6-3-1s is clearance, and extra cost. I seem to remember Pacemakers only having about $40 price difference, going back a bit though.

The biggest factor in exhaust sound is always the muffler. If you choose to go with a chambered type on a 6, you'll need to run a resonator or two with it, otherwise it will drone like a bitch. I have had better success with a straight-through type glasspack which gave a nice presence but was quiet on the open road. 6-2-1 headers, 2.5 system, resonator (basically a hotdog without the packing) and an offset glasspack (side in, centre out). That was on my Cortina and was a great system.

Conversely, when I bought my XE wagon, it was a 6 and had 6-2-1 headers, 2.25 pipes and a turbo-style muffler with a hotdog at the rear. It droned like a mofo, right at the 2100rpm mark where crossies often do. The V8 I put in was quieter.

Don't be fooled by people telling you the pipe size is too big. Any back pressure is bad. People who say that an engine needs back-pressure to run nicely are probably comparing that to open headers, which often don't perform as well as headers with a tuned pipe/collector fitted. That's a pulse tuning issue, not back-pressure.

Smaller pipes are louder. Go as big as you can squeeze in there, and it will cruise sweet but give some bark when you mash it. Small pipes drone and resonate badly.

Sent from my CPH1920 using Tapatalk
 

 

 

 

thats really good information i can understand, thanks for taking the time to type it out much appreciated.

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@gerg Tho Wagons are bad for exhaust resonating through the car, Bros XE wagon has is bad for it,

My bros wagon has same exhaust as on my XF ute (minius cat) no drone on XF but really drones through the wagon when on the highway.

 

My XF utes exhaust sound didn't change much to when I changed from stock manifold & cat, to extractors & hi flow cat with same cat back exhaust,

The exhaust did really change with my new engine tho, became louder & bigger cam makes for a nice idle note,

Pacemakers, 100 cell cat, all 2.5'' (for now) with  Hooker Aerochamber muffler, (3" tip). Videos is some footage I found on my camera, could be from before it was tuned from the hi idle,

 

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[mention=244]gerg[/mention] Tho Wagons are bad for exhaust resonating through the car, Bros XE wagon has is bad for it,

My bros wagon has same exhaust as on my XF ute (minius cat) no drone on XF but really drones through the wagon when on the highway.

 

My XF utes exhaust sound didn't change much to when I changed from stock manifold & cat, to extractors & hi flow cat with same cat back exhaust,

The exhaust did really change with my new engine tho, became louder & bigger cam makes for a nice idle note,

Pacemakers, 100 cell cat, all 2.5'' (for now) with  Hooker Aerochamber muffler, (3" tip). Videos is some footage I found on my camera, could be from before it was tuned from the hi idle,

 

Ford man runs pretty much same exhaust as me on my 4L SOHC.

Pacemaker extractors, high flow cat, 2 1/2" pipe work, Hooker Aerochamber muffler, 2 1/2" into side pipe.

 

Don't dump it at the diff, drone at 110km/hr will shit you after an hour or so.

 

Sent from my S21 using Tapatalk

 

 

 

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[mention=244]gerg[/mention] Tho Wagons are bad for exhaust resonating through the car, Bros XE wagon has is bad for it,

My bros wagon has same exhaust as on my XF ute (minius cat) no drone on XF but really drones through the wagon when on the highway.

 

My XF utes exhaust sound didn't change much to when I changed from stock manifold & cat, to extractors & hi flow cat with same cat back exhaust,

The exhaust did really change with my new engine tho, became louder & bigger cam makes for a nice idle note,

Pacemakers, 100 cell cat, all 2.5'' (for now) with  Hooker Aerochamber muffler, (3" tip). Videos is some footage I found on my camera, could be from before it was tuned from the hi idle,

 

Yes fordman, very true and I forgot to mention this important aspect. I discovered that even a V8 in a wagon has resonant issues that utes and sedans don't, due to the extended cabin area being right over the exhaust outlet with no buffer area like a boot, rear seat or bulkhead to absorb the sound

 

Btw, that's a snappy donk you have there. Hope you get it sorted to run in its prime. I'm predicting mid 14s with the right converter, sharp C4 and hooking up nice

 

Sent from my CPH1920 using Tapatalk

 

 

 

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