My Twin Turbo Build is Under Way
11-02-2008, 03:53 PM
#106
I don't think any dynos "lie". They are machines that operate in accordance with their components and programming.
Will a Mustang dyno provide different results than a DynoJet? Yes, because it operates differently. That said, it is my understanding that a Mustang dyno typically shows less horsepower than a Dynojet. See, e.g.:
http://www.z06vette.com/forums/f55/m...dynojet-47063/
Specifically, here is what is said in that thread:
"Actually...The Mustang Dyno's work slightly different than the Dyno-Jet Dyno's...
Mustang Dyno's apply a load, via eletro-mechanical resistance, then rwhp is calculated based on how your "acceleration/unit of time" of this load occurs...
DynoJet Dyno's simply use a large drum, of know mass, as its rotating resistance...Then rwhp is calculated based on how your "acceleration/unit of time" of the drum occurs...
From what I am told the Mustang dyno gives you a "true" or real world rwhp... i.e. my '00 FRC put down 307 rwhp stock, using 12% drivetrain loss and that is 348 flywheel hp (factory rated 345 hp)...My '02 Z06, on the same Mustang dyno, put down 348 rwhp stock, divide that by 12%, using the same 12% drivetrain loss is 395 fwhp (factory rated at 405 hp)
Dyno Jet Dynos give more of a bragging rights rwhp...
The difference between the two is about 10%...Dyno Jets registering the higher hp readings...
Yours for example...358 rwhp Mustang Dyno vs. 405 rwhp DynoJet...358/405=.884...Pretty close to the 10%...
Last comparison one of the F-body guys posted on LS1.com was the something like the following...338 rwhp Mustang vs. 378 rwhp DynoJet...338/378=.901
On the Mustang dyno that I go to...Stock LS1's in F-body cars dyno in the 280~290 rwhp range...Yet nearly every LS1 F-body that posts rwhp using DynoJet Dynos are in the 310~320 rwhp stock...285/315=0.905
Again...285 rwhp using 12% drivetrain loss gives 324 fwhp, factory rated 320 hp...If you use the DynoJet hp, then you get the following...315 rwhp with 12% drivetrain loss gives 358 fwhp, factory rated 320 hp...So you see, it sound great to think these engines are putting out this kind of power, but it's just not as realistic of a number as you get with the Mustang Dyno...
It really doesn't matter what Dyno you use...Just as long as you keep using the same dyno to check your mods...This will keep variances down to a minimum and tell you truely if any mod is helping or not..."
In the dyno chart posted for my car, the tq/hp numbers have been corrected for temperature and humidity, as I already indicated. I think the uncorrected hp was somewhere in the mid 550's with an ambient temperature somewhere around 90 degrees or so (Jack probably should be able to provide the exact temperature and humidity at the dyno that day, as well as the correction that was applied by the software). But I am perfectly comfortable with these results for now. Would I like to get a dyno run where my rear tires are not spinning on the dyno (and thus wasting hp), and be able to run it all the way to 7500 rpm? Yes, and we will be sure to do that when I go in for my final tune after I get the Cosworth plenum on and get the meth injection on line (hopefully in December).
That said, I am perfectly willing to accept Performance Factory's offer to dyno my car up there. However, considering it is a 3 hour drive each way, and I am completely swamped with work right now (I'm now working 6 days a week at 10-12 hrs a day), I need to be compensated for my time to take an entire day from work to drive up there, get the dyno testing performed on his dyno, and then drive back. (If I'm paid at my standard hourly billing rate, I'll pay for the gas
).
Edit: Also, if anyone has a good suggestion on how to get the Greddy's to spool up earlier in the RPM band without going to an exhaust system that is louder than what I already have, I would like to hear it.
Will a Mustang dyno provide different results than a DynoJet? Yes, because it operates differently. That said, it is my understanding that a Mustang dyno typically shows less horsepower than a Dynojet. See, e.g.:
http://www.z06vette.com/forums/f55/m...dynojet-47063/
Specifically, here is what is said in that thread:
"Actually...The Mustang Dyno's work slightly different than the Dyno-Jet Dyno's...
Mustang Dyno's apply a load, via eletro-mechanical resistance, then rwhp is calculated based on how your "acceleration/unit of time" of this load occurs...
DynoJet Dyno's simply use a large drum, of know mass, as its rotating resistance...Then rwhp is calculated based on how your "acceleration/unit of time" of the drum occurs...
From what I am told the Mustang dyno gives you a "true" or real world rwhp... i.e. my '00 FRC put down 307 rwhp stock, using 12% drivetrain loss and that is 348 flywheel hp (factory rated 345 hp)...My '02 Z06, on the same Mustang dyno, put down 348 rwhp stock, divide that by 12%, using the same 12% drivetrain loss is 395 fwhp (factory rated at 405 hp)
Dyno Jet Dynos give more of a bragging rights rwhp...
The difference between the two is about 10%...Dyno Jets registering the higher hp readings...
Yours for example...358 rwhp Mustang Dyno vs. 405 rwhp DynoJet...358/405=.884...Pretty close to the 10%...
Last comparison one of the F-body guys posted on LS1.com was the something like the following...338 rwhp Mustang vs. 378 rwhp DynoJet...338/378=.901
On the Mustang dyno that I go to...Stock LS1's in F-body cars dyno in the 280~290 rwhp range...Yet nearly every LS1 F-body that posts rwhp using DynoJet Dynos are in the 310~320 rwhp stock...285/315=0.905
Again...285 rwhp using 12% drivetrain loss gives 324 fwhp, factory rated 320 hp...If you use the DynoJet hp, then you get the following...315 rwhp with 12% drivetrain loss gives 358 fwhp, factory rated 320 hp...So you see, it sound great to think these engines are putting out this kind of power, but it's just not as realistic of a number as you get with the Mustang Dyno...
It really doesn't matter what Dyno you use...Just as long as you keep using the same dyno to check your mods...This will keep variances down to a minimum and tell you truely if any mod is helping or not..."
In the dyno chart posted for my car, the tq/hp numbers have been corrected for temperature and humidity, as I already indicated. I think the uncorrected hp was somewhere in the mid 550's with an ambient temperature somewhere around 90 degrees or so (Jack probably should be able to provide the exact temperature and humidity at the dyno that day, as well as the correction that was applied by the software). But I am perfectly comfortable with these results for now. Would I like to get a dyno run where my rear tires are not spinning on the dyno (and thus wasting hp), and be able to run it all the way to 7500 rpm? Yes, and we will be sure to do that when I go in for my final tune after I get the Cosworth plenum on and get the meth injection on line (hopefully in December).
That said, I am perfectly willing to accept Performance Factory's offer to dyno my car up there. However, considering it is a 3 hour drive each way, and I am completely swamped with work right now (I'm now working 6 days a week at 10-12 hrs a day), I need to be compensated for my time to take an entire day from work to drive up there, get the dyno testing performed on his dyno, and then drive back. (If I'm paid at my standard hourly billing rate, I'll pay for the gas
).Edit: Also, if anyone has a good suggestion on how to get the Greddy's to spool up earlier in the RPM band without going to an exhaust system that is louder than what I already have, I would like to hear it.
Last edited by ttg35fort; 11-02-2008 at 04:17 PM.
11-02-2008, 07:50 PM
#107
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I've read a lot of Inertia vs. Load Based dyno reports and analyses and my conclusion is that they are both adequate for tuning purposes, but since you cannot adjust load on a Dynojet, there is no "number adjustment" that is possible, unlike a load-based dyno. As for tuning the conclusion I came up with is that load-based dynos make tuning easier, but a skilled tuner will be just as well off with an inertia dyno.
If I am just comparing power levels with someone else I would prefer to use a dynojet.
Just my 2 cents and correct me if I'm wrong; always learning.
If I am just comparing power levels with someone else I would prefer to use a dynojet.
Just my 2 cents and correct me if I'm wrong; always learning.
11-02-2008, 08:22 PM
#108
I've read a lot of Inertia vs. Load Based dyno reports and analyses and my conclusion is that they are both adequate for tuning purposes, but since you cannot adjust load on a Dynojet, there is no "number adjustment" that is possible, unlike a load-based dyno. As for tuning the conclusion I came up with is that load-based dynos make tuning easier, but a skilled tuner will be just as well off with an inertia dyno.
If I am just comparing power levels with someone else I would prefer to use a dynojet.
Just my 2 cents and correct me if I'm wrong; always learning.
If I am just comparing power levels with someone else I would prefer to use a dynojet.
Just my 2 cents and correct me if I'm wrong; always learning.
11-02-2008, 08:32 PM
#109
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Oh I completely agree with you there, load-based dynos seem to record low.
Except on a Dynojet, you can't adjust load (obviously), which means you can't tamper with the numbers.
On a load-based dyno, you can adjust it until the "results" are to your liking.
I am not saying his tuner was doing that! Just for the purposes of a "test" I would feel better using a dynojet.
Except on a Dynojet, you can't adjust load (obviously), which means you can't tamper with the numbers.
On a load-based dyno, you can adjust it until the "results" are to your liking.
I am not saying his tuner was doing that! Just for the purposes of a "test" I would feel better using a dynojet.
11-02-2008, 08:42 PM
#110
Registered User
They can all be adjusted....with a DJ just change the weather station settings and voila.
And on SP's mustang dyno in 70 degree dry weather I did 511rwhp, exact same settings in humid conditions (was drizzlin) on a dynapac I did 546....so its just a tool to measure changes.
Nice numbers though on this build......how do you like the C2 cams?
I was like you and did it all at once....quite a change from 232rwhp to almost 800rwhp lol
And on SP's mustang dyno in 70 degree dry weather I did 511rwhp, exact same settings in humid conditions (was drizzlin) on a dynapac I did 546....so its just a tool to measure changes.
Nice numbers though on this build......how do you like the C2 cams?
I was like you and did it all at once....quite a change from 232rwhp to almost 800rwhp lol
Oh I completely agree with you there, load-based dynos seem to record low.
Except on a Dynojet, you can't adjust load (obviously), which means you can't tamper with the numbers.
On a load-based dyno, you can adjust it until the "results" are to your liking.
I am not saying his tuner was doing that! Just for the purposes of a "test" I would feel better using a dynojet.
Except on a Dynojet, you can't adjust load (obviously), which means you can't tamper with the numbers.
On a load-based dyno, you can adjust it until the "results" are to your liking.
I am not saying his tuner was doing that! Just for the purposes of a "test" I would feel better using a dynojet.
11-02-2008, 08:58 PM
#111
mustang dynos are the easiest to manipulate. Everyone knows that. Dynojets have no corrections to put in. That's why I would offer a free pull or two to him for comparison. No I'm not kidding captj. He is claiming 600 on 14 psi. That car would barely make 550 on a true Dynojet at that boost levels.
Last edited by Audible Mayhem; 11-02-2008 at 09:01 PM.
11-02-2008, 09:13 PM
#112
Oh I completely agree with you there, load-based dynos seem to record low.
Except on a Dynojet, you can't adjust load (obviously), which means you can't tamper with the numbers.
On a load-based dyno, you can adjust it until the "results" are to your liking.
I am not saying his tuner was doing that! Just for the purposes of a "test" I would feel better using a dynojet.
Except on a Dynojet, you can't adjust load (obviously), which means you can't tamper with the numbers.
On a load-based dyno, you can adjust it until the "results" are to your liking.
I am not saying his tuner was doing that! Just for the purposes of a "test" I would feel better using a dynojet.
In the end it doesn't matter what the dyno says, it's how the car performs. I like the way my car is performing, so all is well.
Last edited by ttg35fort; 11-02-2008 at 09:50 PM.
11-02-2008, 09:48 PM
#113
mustang dynos are the easiest to manipulate. Everyone knows that. Dynojets have no corrections to put in. That's why I would offer a free pull or two to him for comparison. No I'm not kidding captj. He is claiming 600 on 14 psi. That car would barely make 550 on a true Dynojet at that boost levels.
Since it seems so important to you guys, just compensate me for my time. I am perfectly willing to send Performance Factory my standard retainer agreement. Once I have a properly executed retainer agreement and I have a retainer for 8 hours of my time at my standard billing rate, I'll agree to drive my car to Performance Factory to be tested on the DynoJet.
Alternatively (and it will probably be much cheaper) schedule a flatbead to pick up my car up from Japtrix to be sent strait from Japtrix to Sharif at Forged Performance. Let Sharif test it on his dyno, then have Sharif send my car staight back to Japtrix. We'll let Sharif post the results of the dyno. I will agree to that as well, and I won't charge you a dime for this use of my car. Obviously, you will need to pay for the transportation of my car to and from Forged Performance, as well as compensate Forged Performance for the dyno testing.
Last edited by ttg35fort; 11-02-2008 at 09:54 PM.
11-03-2008, 08:00 AM
#116
I have the car setup for the road course, not the drag strip.... (e.g. camber settings, tires, etc.) Moreover, I have the DDS level 2 axles. They are more than adequate for over 600 hp on the road course, but are only rated to 500 hp on the drag strip.
11-03-2008, 03:32 PM
#118
I am perfectly fine with my dyno results, as I previously indicated. I never asked to throw my car on another dyno, Jeremy asked me.
Evidentially Jtrain (on the G35 forum) is not happy with his tune, and it appears that he really respects Jeremy. Thus, it would be really cool if Jeremy would extend the same offer to Jtrain that he made to me. I think Jtrain would very much appreciate getting Jeremy to take a look at his tune on the dyno, and maybe even do some tweaking while he is at it. Obviously, this is completely up to Jeremy, but this would still allow Jeremy to compare his dyno results to Japtrix’s results, while actually helping somebody that seems to want the help.
Evidentially Jtrain (on the G35 forum) is not happy with his tune, and it appears that he really respects Jeremy. Thus, it would be really cool if Jeremy would extend the same offer to Jtrain that he made to me. I think Jtrain would very much appreciate getting Jeremy to take a look at his tune on the dyno, and maybe even do some tweaking while he is at it. Obviously, this is completely up to Jeremy, but this would still allow Jeremy to compare his dyno results to Japtrix’s results, while actually helping somebody that seems to want the help.
11-03-2008, 04:21 PM
#120
Just for reference, my car makes 602rwhp @ 14.5 psi on 91 octane, with water injection @ ONLY ~8% W/FR - Dynojet of course
Congrats on the build, you will love the power once you are done with the break-in, my biggest problem is traction - on the freeway!
Congrats on the build, you will love the power once you are done with the break-in, my biggest problem is traction - on the freeway!
Last edited by GTM; 11-03-2008 at 04:25 PM.