A BIG THANK YOU TO JOSH AND HIGH HORSE PERFORMANCE, HARDWARE SPONSOR FOR THE GIFO3 SERIES OF TESTS.
Test Information
Date: 10/21/05
Dyno Time: 9:00 - 5pm
Dyno Temp Range: 65 - 80 degrees F
Dyno Location: SVS Automotive Research and Development Dept, Sacramento (www.svsrnd.com)
Dyno Driver and test administrator: Bob Crespo of SVS R and D
Dynamometer: Superflow AutoDyn SF 840 Chassis
Dyno Setup: All tests were run with a fan blowing from the front of the vehicle as well as across the tail area.
Dyno Raw Data: Coming soon.
Results Summary
Where to start? There was so many things going on this day. Much of it did nothing but raise more questions and lead to more confusion. Let's just start at the top.
Headers:
I think it's pretty clear that the headers are indeed worth some hp and trq gains. At first look, you might think what we all thought; comparing the average of the runs just before and just after shows a net of 20hp and 22torque. But, as you look closer at the data, something starts to seem… strange (the word of the day)
First, its important to realize that a battery disconnect is required to install the headers. So, if we take as fact that the PCM has no settings to loose, we should be able to claim the reset has no bearing on the results. But, look at these graphs:
HP
Torque
Notice something? After the headers were installed, our famous tranny dip shows its ugly face. But, and we confirmed this, the GSM traction mod was turned on. Why does the traction modification not work after a battery disconnect? (more on this later)
So, can we say the headers are worth 20/22? Maybe. I hesitate to assert it as fact, however, since there is clearly something going on in the torque management; something I could not control. Could it be the battery disconnect had some effect beyond throttle response?
GSM Traction Modification:
This is where things get really weird. As I understand it, the whole point of the mod is to limit the dip in hp and trq that accompanies each shift of the gears. The theory is, by removing this dip, time is saved and therefore we should get faster ¼ times. The above charts show this difference.
Now, take a look at this:
You're looking at an overlay of two runs, that only differed by a flip of the switch (turning the GSM mod on). Notice that there is no dip. It would seem the tranny is acting like the GSM mod is on all the time. We didn't just see this on my car; we saw it on Meister's as well across multiple runs.
This I find very disturbing. The potential safety implications alone are enough to justify the concern; how can I be sure my traction control is functioning properly? What is it about this mod that changes the circuit to the point where the tranny acts totally differently now that it's installed? Could this be a characteristic of the tranny itself, and thus the GSM mod in fact does nothing? So many questions, that seem to have no answers…
Here is another issue. Take a look at these:
HP
Trq
These two runs were consecutively made. The battery was disconnected before set 7, and you can see that the first two runs in set 7 behave as though the mod was not turned on. The last three runs in set 7 behave as though the mod was turned on (it was turned on for all 5; see above for a discussion on this). This graph shows runs 2 and 3. The thing I found interesting here is how the HP begins to dip much sooner than the standard shift. Even though the hp doesn't drop so dramatically, the power does diminish far sooner than expected. Wouldn't this tend to give back all the time we gained by a smaller dip? Perhaps that is why we saw basically zero improvement at the track.
K&N Aircharger vs The Stock Box:
I think we've finally reached the point where we might have realized a restriction in the stock box. Take a look at sets 4 and 5. I'm actually shocked to see that by removing the K&N Aircharger, I gave up 12/13. Still no where near the advertised 21, but we're gaining on it.
20" vs. 18" Rims and Tires:
If anything, the numbers show an improvement with the 20"s. I was unable to weigh these setups, but based on published numbers, the 20"s come in a few lbs heavier than the stocks.
203f vs. 170f Thermostat:
This was a spur of the moment test. Meister was able to track down a 170f thermo at the local Kragen, so we gave it a go. The numbers seem to show a 10/5 improvement. Well worth the $7!
Other items of note:
You may have noticed that the numbers before the header install were way down from the GIFO2 (almost 12/12). Bob, and the gang poured over the numbers and threw ideas around as to why this might be the case. The best theory we came up with relates to the STP correction factor; on this day, the factor was nearly 1:1. So, whatevier the dyno read is the number we've got. However, the GIFO2 had a significant factor applied (the ambient temps were 105f or so!). The thought is at the extreme temps, the correction overcompensates, thus yielding higher than normal numbers.
The other significantly more troubling theory relates to the GSM mod. As pointed out above, the tranny seems to react as though the mod was engaged even when it wasn't. This could indicate a problem that the computer is just handling by limiting output. I have no real proof of this, but I'm really not sure what else it could be. The dyno was calibrated correctly; I had the same gas in it, at the same level… any other thoughts?
In any case, its the relative changes that are important. This is precisely why we try to run one car, on the same day at basically the same time with many different setups. It is almost impossible to compare these numbers with the GIFO2 or GIFO1. There are just too many things that could be different. However, comparing runs made in short order, in a fairly controlled environment is, in my opinion, a very valid way to derive the conclusions (and questions) we now have.
Track data:
Test Information
Date: 10/21/05
Dyno Time: 9:00 - 5pm
Dyno Temp Range: 65 - 80 degrees F
Dyno Location: SVS Automotive Research and Development Dept, Sacramento (www.svsrnd.com)
Dyno Driver and test administrator: Bob Crespo of SVS R and D
Dynamometer: Superflow AutoDyn SF 840 Chassis
Dyno Setup: All tests were run with a fan blowing from the front of the vehicle as well as across the tail area.
Dyno Raw Data: Coming soon.
Results Summary
Where to start? There was so many things going on this day. Much of it did nothing but raise more questions and lead to more confusion. Let's just start at the top.
Headers:
I think it's pretty clear that the headers are indeed worth some hp and trq gains. At first look, you might think what we all thought; comparing the average of the runs just before and just after shows a net of 20hp and 22torque. But, as you look closer at the data, something starts to seem… strange (the word of the day)
First, its important to realize that a battery disconnect is required to install the headers. So, if we take as fact that the PCM has no settings to loose, we should be able to claim the reset has no bearing on the results. But, look at these graphs:
HP
Torque
Notice something? After the headers were installed, our famous tranny dip shows its ugly face. But, and we confirmed this, the GSM traction mod was turned on. Why does the traction modification not work after a battery disconnect? (more on this later)
So, can we say the headers are worth 20/22? Maybe. I hesitate to assert it as fact, however, since there is clearly something going on in the torque management; something I could not control. Could it be the battery disconnect had some effect beyond throttle response?
GSM Traction Modification:
This is where things get really weird. As I understand it, the whole point of the mod is to limit the dip in hp and trq that accompanies each shift of the gears. The theory is, by removing this dip, time is saved and therefore we should get faster ¼ times. The above charts show this difference.
Now, take a look at this:
You're looking at an overlay of two runs, that only differed by a flip of the switch (turning the GSM mod on). Notice that there is no dip. It would seem the tranny is acting like the GSM mod is on all the time. We didn't just see this on my car; we saw it on Meister's as well across multiple runs.
This I find very disturbing. The potential safety implications alone are enough to justify the concern; how can I be sure my traction control is functioning properly? What is it about this mod that changes the circuit to the point where the tranny acts totally differently now that it's installed? Could this be a characteristic of the tranny itself, and thus the GSM mod in fact does nothing? So many questions, that seem to have no answers…
Here is another issue. Take a look at these:
HP
Trq
These two runs were consecutively made. The battery was disconnected before set 7, and you can see that the first two runs in set 7 behave as though the mod was not turned on. The last three runs in set 7 behave as though the mod was turned on (it was turned on for all 5; see above for a discussion on this). This graph shows runs 2 and 3. The thing I found interesting here is how the HP begins to dip much sooner than the standard shift. Even though the hp doesn't drop so dramatically, the power does diminish far sooner than expected. Wouldn't this tend to give back all the time we gained by a smaller dip? Perhaps that is why we saw basically zero improvement at the track.
K&N Aircharger vs The Stock Box:
I think we've finally reached the point where we might have realized a restriction in the stock box. Take a look at sets 4 and 5. I'm actually shocked to see that by removing the K&N Aircharger, I gave up 12/13. Still no where near the advertised 21, but we're gaining on it.
20" vs. 18" Rims and Tires:
If anything, the numbers show an improvement with the 20"s. I was unable to weigh these setups, but based on published numbers, the 20"s come in a few lbs heavier than the stocks.
203f vs. 170f Thermostat:
This was a spur of the moment test. Meister was able to track down a 170f thermo at the local Kragen, so we gave it a go. The numbers seem to show a 10/5 improvement. Well worth the $7!
Other items of note:
You may have noticed that the numbers before the header install were way down from the GIFO2 (almost 12/12). Bob, and the gang poured over the numbers and threw ideas around as to why this might be the case. The best theory we came up with relates to the STP correction factor; on this day, the factor was nearly 1:1. So, whatevier the dyno read is the number we've got. However, the GIFO2 had a significant factor applied (the ambient temps were 105f or so!). The thought is at the extreme temps, the correction overcompensates, thus yielding higher than normal numbers.
The other significantly more troubling theory relates to the GSM mod. As pointed out above, the tranny seems to react as though the mod was engaged even when it wasn't. This could indicate a problem that the computer is just handling by limiting output. I have no real proof of this, but I'm really not sure what else it could be. The dyno was calibrated correctly; I had the same gas in it, at the same level… any other thoughts?
In any case, its the relative changes that are important. This is precisely why we try to run one car, on the same day at basically the same time with many different setups. It is almost impossible to compare these numbers with the GIFO2 or GIFO1. There are just too many things that could be different. However, comparing runs made in short order, in a fairly controlled environment is, in my opinion, a very valid way to derive the conclusions (and questions) we now have.
Track data: