Torque cones?
Seasoned HDF Member
Joined: Aug 2008
Posts: 5,048
Likes: 990
there is some confusion when you mention torque cones so do you mean header pipe or exiting position.
these are like drag pipes and WILL have drops and hard to tune out but you can come close.
the cones used in the header are hit and miss, mostly miss. they operate in a very narrow band and outside it, no improvement, maybe more likely loss.
if you do not ride in that band, waste of money. the theory is that the reduction in the port will cause a low pressure area and supposedly help the following exhaust stroke.
liken this to headers on a car, when the pulse enters the collector, a low pressure is created which helps the next cyl, BUT, to make them street-able friendly, a spool is used and this spool is tuned in with a dyno.
open header is great for WOT and non restrictive piping.
ugly to some but a balance tube between the two will help.
these are like drag pipes and WILL have drops and hard to tune out but you can come close.
the cones used in the header are hit and miss, mostly miss. they operate in a very narrow band and outside it, no improvement, maybe more likely loss.
if you do not ride in that band, waste of money. the theory is that the reduction in the port will cause a low pressure area and supposedly help the following exhaust stroke.
liken this to headers on a car, when the pulse enters the collector, a low pressure is created which helps the next cyl, BUT, to make them street-able friendly, a spool is used and this spool is tuned in with a dyno.
open header is great for WOT and non restrictive piping.
ugly to some but a balance tube between the two will help.
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Cruiser
Joined: Mar 2009
Posts: 204
Likes: 25
there is some confusion when you mention torque cones so do you mean header pipe or exiting position.
these are like drag pipes and WILL have drops and hard to tune out but you can come close.
the cones used in the header are hit and miss, mostly miss. they operate in a very narrow band and outside it, no improvement, maybe more likely loss.
if you do not ride in that band, waste of money. the theory is that the reduction in the port will cause a low pressure area and supposedly help the following exhaust stroke.
liken this to headers on a car, when the pulse enters the collector, a low pressure is created which helps the next cyl, BUT, to make them street-able friendly, a spool is used and this spool is tuned in with a dyno.
open header is great for WOT and non restrictive piping.
ugly to some but a balance tube between the two will help.
these are like drag pipes and WILL have drops and hard to tune out but you can come close.
the cones used in the header are hit and miss, mostly miss. they operate in a very narrow band and outside it, no improvement, maybe more likely loss.
if you do not ride in that band, waste of money. the theory is that the reduction in the port will cause a low pressure area and supposedly help the following exhaust stroke.
liken this to headers on a car, when the pulse enters the collector, a low pressure is created which helps the next cyl, BUT, to make them street-able friendly, a spool is used and this spool is tuned in with a dyno.
open header is great for WOT and non restrictive piping.
ugly to some but a balance tube between the two will help.
The torque cones that Samson sells are at the header pipe. And I’m not smart enough to understand why or why not to use them. When I searched, they were post about 10 years ago where it seemed like most people said don’t bother and I didn’t know if time has changed that answer.
and thank you for the response
Last edited by bmedeiros678; Aug 28, 2024 at 06:57 PM.
Road Warrior
Joined: Dec 2015
Posts: 1,826
Likes: 1,046
From: Southwest Desert
I used them in my cammed Evo with shorter drag pipes for 10 years. Someone way more knowledgeable told me that they make your engine think your exhaust is longer and does something to the "pulse" or "reversion" point in your exhaust. They move it farther back. I was also told to use half baffles in my drag pipes. I never dyno'd, but my bike ran really well (WOT) and had no popping on decel with those mods...someone else told me that torque cones dimmish your top end RPM HP and torque curves. Since all the fun of owning a Harley is between 25 mph and 100mph, I say try them. They are relatively inexpensive and take 15 minutes to install or remove. I currently run a 2/1 pipe, so I don't use them anymore. But I would use them again, if I ever put on some short drag pipes again. I even tried fabricating some lollipop baffles, and they really didn't work very well. But that's another discussion...
Last edited by SirHarley; Aug 30, 2024 at 09:40 AM. Reason: corrections
Seasoned HDF Member
Joined: Aug 2008
Posts: 5,048
Likes: 990
if you want to get a grip on the concept, study gas flow through an orifice.
the same principle is used in expansion chambers on two cycles. there is one diff in that the system is tuned via a stinger, sorta like the piece that dips the fence last on a chicken.
IF they work at all, it will be a VERY narrow band.
i usually tell this story:
a dude comes up and says he installed headers on his truck and now he has 20% more power, hummmmm????
i ask him did he tune it in, what do you mean he says??? it states on the box they are tuned headers!!!!!!
yep, i say they are tuned on the primary because the tubes are equal length, BUT remember, not all engines fire the same so there will be variations.
what did you do with the spool piece that came with the headers??? i say that is a short pipe that bolts to the header flange, it is used to tune the header. well he says, i threw it away as i did not need it, i bolted my mufflers right up to the header.
??????? hummm i say you probably lost power then.
that little piece is bolted to the header and then dyno run and then trim tiny pieces off till you see a rise and the a fall, that is the sweet spot for that flow rate. remember, you have to design around your intended purpose for the vehicle.
as a kicker, the exiting exhaust pipe is painted and then run and a balance tube is added where the paint burns.
so hd with their balance tubes are not doing it for grins and giggles!
long story short, johnny up the street on his western flyer will smoke ya!
the same principle is used in expansion chambers on two cycles. there is one diff in that the system is tuned via a stinger, sorta like the piece that dips the fence last on a chicken.
IF they work at all, it will be a VERY narrow band.
i usually tell this story:
a dude comes up and says he installed headers on his truck and now he has 20% more power, hummmmm????
i ask him did he tune it in, what do you mean he says??? it states on the box they are tuned headers!!!!!!
yep, i say they are tuned on the primary because the tubes are equal length, BUT remember, not all engines fire the same so there will be variations.
what did you do with the spool piece that came with the headers??? i say that is a short pipe that bolts to the header flange, it is used to tune the header. well he says, i threw it away as i did not need it, i bolted my mufflers right up to the header.
??????? hummm i say you probably lost power then.
that little piece is bolted to the header and then dyno run and then trim tiny pieces off till you see a rise and the a fall, that is the sweet spot for that flow rate. remember, you have to design around your intended purpose for the vehicle.
as a kicker, the exiting exhaust pipe is painted and then run and a balance tube is added where the paint burns.
so hd with their balance tubes are not doing it for grins and giggles!
long story short, johnny up the street on his western flyer will smoke ya!
Grand HDF Member
Joined: Sep 2022
Posts: 4,247
Likes: 3,668
From: Florida
They were designed to help with reversion.. they do work “kinda”. You’re better off with Thumb screws or DKCustoms Thunder Torque inserts.
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Intermediate
Joined: Mar 2021
Posts: 40
Likes: 12
From: Hollister
Nope
They have shown a bit of improvement in straight thru shortys.
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