Advanced Resonance Tuning (ART pipes)
#261
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MOTORDYNE-MY350Z SPONSOR
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Shoot... I was thinking you had HFC's. HFC Vs HFC is a comparison I would like to see. I think most everyone else who did comparisons has some other kind of after market catback.
This comparison is open to anyone who can do such a test!
Test pipe comparisons too!
This comparison is open to anyone who can do such a test!
Test pipe comparisons too!
#266
#267
great news Tony! keep up the good work buddy. but don't rush it we want you to take time and make the best of it
Now that you have DE model as a bench mark, lets make the HR one even better!
#270
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MOTORDYNE-MY350Z SPONSOR
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Yes.
2 HFC's flow more than one HFC. But A HFC placed further away from the engine makes more power as well. The reason for doing this test is to see which setup makes more power.
Also, if the Motordyne HFC can demonstrate similar (or greater) power than traditional HFC's, there is a great functional advantage gained. Having the HFC located behind the XYZ pipe makes access to it much, much easier. And this give the user the ability to easily swap out the HFC for a straight pipe or resonator. Allowing smell free performance for daily driving (with the HFC) or additional performance for the track (with the resonator or straight pipe).
Many people have asked in this forum "Which should I get, test pipes or HFC's?" This is a common question and the reason is because there is a compromise one way or the other.
Test pipes yeild higher performance but they rasp, drone and smell.
HFC's yeild lower performance but they reduce rasp, drone and smell.
So with either setup there is an unavoidable compromise associated with the choice made. And once the traditional test pipes or HFC's are installed, they will typically stay there permanently because access to them is so difficult. Swapping test pipes for HFC's is not practical for most people. Who wants to make that compromise?
But there is another option.
By moving the HFC to underneath the car, as is done with the XYZ HFC, changing one out a HFC for a straight pipe becomes vastly easier to do. With this setup it is now a practical and viable option to have the best of both worlds. Now you can install the test pipes (or ART pipes) for the higher power. This is becomes the baseline configuration. You can use this setup for optimum track performance.
And if/when you would prefer the reduced smell and emissions of a HFC for your daily drive to work, you can have that too. Putting the HFC underneath the car where it is easily accessed allows you the option to change from a straight pipe to a HFC as needed. And very easily. You can switch from one to the other with 2 jack stands and by turning 3 bolts. So with the XYZ setup, you don't have to settle on a compromise.
Having the HFC attached to the XYZ pipe has its clear functional and practical advantages. So only one question remains... What are the relative differences in power between the XYZ HFC and traditional HFC's?
This will make a good dyno test.
2 HFC's flow more than one HFC. But A HFC placed further away from the engine makes more power as well. The reason for doing this test is to see which setup makes more power.
Also, if the Motordyne HFC can demonstrate similar (or greater) power than traditional HFC's, there is a great functional advantage gained. Having the HFC located behind the XYZ pipe makes access to it much, much easier. And this give the user the ability to easily swap out the HFC for a straight pipe or resonator. Allowing smell free performance for daily driving (with the HFC) or additional performance for the track (with the resonator or straight pipe).
Many people have asked in this forum "Which should I get, test pipes or HFC's?" This is a common question and the reason is because there is a compromise one way or the other.
Test pipes yeild higher performance but they rasp, drone and smell.
HFC's yeild lower performance but they reduce rasp, drone and smell.
So with either setup there is an unavoidable compromise associated with the choice made. And once the traditional test pipes or HFC's are installed, they will typically stay there permanently because access to them is so difficult. Swapping test pipes for HFC's is not practical for most people. Who wants to make that compromise?
But there is another option.
By moving the HFC to underneath the car, as is done with the XYZ HFC, changing one out a HFC for a straight pipe becomes vastly easier to do. With this setup it is now a practical and viable option to have the best of both worlds. Now you can install the test pipes (or ART pipes) for the higher power. This is becomes the baseline configuration. You can use this setup for optimum track performance.
And if/when you would prefer the reduced smell and emissions of a HFC for your daily drive to work, you can have that too. Putting the HFC underneath the car where it is easily accessed allows you the option to change from a straight pipe to a HFC as needed. And very easily. You can switch from one to the other with 2 jack stands and by turning 3 bolts. So with the XYZ setup, you don't have to settle on a compromise.
Having the HFC attached to the XYZ pipe has its clear functional and practical advantages. So only one question remains... What are the relative differences in power between the XYZ HFC and traditional HFC's?
This will make a good dyno test.
#271
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MOTORDYNE-MY350Z SPONSOR
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Then there is the application for forced induction....
Many people who have FI are also confronted with this same compromise but the compromise is multiplied greatly. Many people want HFC's with their supercharger or turbo but it comes at a much greater power loss.
Then there is also the issue of durability. With NA or FI, durability and reliability is an issue with many metal based cats. Ceramic is more reliable but it doesn't flow as well either.
The problem with the metal cats failing is because of mechanical and thermal issues.
1) The closer a catalytic converter is to the engine, the more heat it will be exposed to. I've measured it on the FCON where EGT at the outlet of the header is ~1200 deg F. At the outlet of the test pipe there is a huge drop in temperature ~300 deg F. At the outlet of the XYZ pipe the temperature will likely drop another 100-200 deg F. ...if the same HFC substrate is exposed to 400-500 deg F lower temperatures it will certainly help to increase the HFC life expectancy.
2) The mechanical effects will also be greatly reduced if placed further away from the engine. With each exhaust pulse coming out of the engine the pulse is a violent event like a shotgun blast (at 4-7 K RPM). The further away the cat can be moved away from the source of the blast the intensity of the blast is reduced. The reduced mechanical shock will help to increase the HFC life expectancy.
And if forced induction is involved these issues are multiplied significantly.
So there are reasons to move the HFC away from the engine and to a location that makes it easy to change out as needed by the application.
Many people who have FI are also confronted with this same compromise but the compromise is multiplied greatly. Many people want HFC's with their supercharger or turbo but it comes at a much greater power loss.
Then there is also the issue of durability. With NA or FI, durability and reliability is an issue with many metal based cats. Ceramic is more reliable but it doesn't flow as well either.
The problem with the metal cats failing is because of mechanical and thermal issues.
1) The closer a catalytic converter is to the engine, the more heat it will be exposed to. I've measured it on the FCON where EGT at the outlet of the header is ~1200 deg F. At the outlet of the test pipe there is a huge drop in temperature ~300 deg F. At the outlet of the XYZ pipe the temperature will likely drop another 100-200 deg F. ...if the same HFC substrate is exposed to 400-500 deg F lower temperatures it will certainly help to increase the HFC life expectancy.
2) The mechanical effects will also be greatly reduced if placed further away from the engine. With each exhaust pulse coming out of the engine the pulse is a violent event like a shotgun blast (at 4-7 K RPM). The further away the cat can be moved away from the source of the blast the intensity of the blast is reduced. The reduced mechanical shock will help to increase the HFC life expectancy.
And if forced induction is involved these issues are multiplied significantly.
So there are reasons to move the HFC away from the engine and to a location that makes it easy to change out as needed by the application.
#272
There is no doubt your design gives plenty of options over the comp. I was thinking the dyno comparison would yield little to no difference, since your HFC is moved down stream. There is also the added benefit of cooler EGT's at the heads. As long as your HFC is large enough, I think a single cat moved down stream might have better power results.
Even then with the ability to swap cat for straight pipe in approx. 30 min., would have much more function over a slight loss of power. Thanks for the explanation, I was curious.
Even then with the ability to swap cat for straight pipe in approx. 30 min., would have much more function over a slight loss of power. Thanks for the explanation, I was curious.
#273
My last tune was for TPs, but I had to put the stock cats back on for sound at Laguna. Meaning, that we'll still have a back-to-back of stock cats to ART with the current tune, but even better that there will be an additional tuned comparison of TPs to ART. After that, Rob will see if further tuning can produce additional power with the ART pipes. Power that I need since the 370 is way faster than me in the long straight from T11 to T2 at Laguna. Picking up the extrq TQ will be welcome, and maybe we'll make 270rwhp!
Tuned 2" test pipes vs tuned ART pipes (different day - temp was ~3F cooler, pressure and humidity were about identical, correction factor was identical). Next we are going to see if it'll pick up some power with a better intake.
And here is another one with another run from a previous tuning session a month before to contrast how much (or little) day-to-day changes affect the results.
Last edited by scotts300; 04-19-2010 at 07:20 AM.
#276
Quoting myself from a few months ago now that the car is tuned for the ART pipes - 271rwhp/252rwtq!
Well here ya go!
Tuned 2" test pipes vs tuned ART pipes (different day - temp was ~3F cooler, pressure and humidity were about identical, correction factor was identical). Next we are going to see if it'll pick up some power with a better intake.
And here is another one with another run from a previous tuning session a month before to contrast how much (or little) day-to-day changes affect the results.
Well here ya go!
Tuned 2" test pipes vs tuned ART pipes (different day - temp was ~3F cooler, pressure and humidity were about identical, correction factor was identical). Next we are going to see if it'll pick up some power with a better intake.
And here is another one with another run from a previous tuning session a month before to contrast how much (or little) day-to-day changes affect the results.
Nice numbers man.
What about the difference in driveability?
As far as your set-up, do you think the pulley's have any affect on your numbers?
Are you experiencing heatsoak w/ the k/n intake?
#278
Thanks!
Good question - I'm not sure, but will look into it.
Thanks! The driveability is way different. I ran two autoxs this weekend, and the added power coming out of turns was obvious. I believe the pulleys do help, but I bought the car with them so don't have anything to baseline it against. Heatsoak of the K&N is the concern Z Car Garage has on my set up, so we'll make the change soon and see for sure.
Their procedure is WOT when they hit the record button, so I believe it's real.
Good question - I'm not sure, but will look into it.
Their procedure is WOT when they hit the record button, so I believe it's real.
#279
#280
[quote=scotts300;8314787]Thanks!
Good question - I'm not sure, but will look into it.
Thanks! The driveability is way different. I ran two autoxs this weekend, and the added power coming out of turns was obvious. I believe the pulleys do help, but I bought the car with them so don't have anything to baseline it against. Heatsoak of the K&N is the concern Z Car Garage has on my set up, so we'll make the change soon and see for sure.
Yeah, I make pretty good power with my few mods minus the intake on Tony's suggestion that intakes rob power from heatsoak in his testing.
That being the case I still want to add a popcharger and see if i gan a few horses or not.
Good question - I'm not sure, but will look into it.
Thanks! The driveability is way different. I ran two autoxs this weekend, and the added power coming out of turns was obvious. I believe the pulleys do help, but I bought the car with them so don't have anything to baseline it against. Heatsoak of the K&N is the concern Z Car Garage has on my set up, so we'll make the change soon and see for sure.
Yeah, I make pretty good power with my few mods minus the intake on Tony's suggestion that intakes rob power from heatsoak in his testing.
That being the case I still want to add a popcharger and see if i gan a few horses or not.