The Cobalt Ss/sc: Got Boost?
07-13-2006, 08:14 PM
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The Cobalt Ss/sc: Got Boost?
THE COBALT SS/SC: GOT BOOST?
By: Denny Medeiros, Cobaltss.net
You might have read my last review, where you learned that freeing up the intake did wonders in helping the LSJ Engine breathe better. Now it’s time to step it up a notch, with some added Boost!
According to calculations, the stock (34 lb/hr) injectors on the Cobalt SS/SC can still provide enough fuel for another 30 HP over factory at 80% duty cycle. Here is the formula:
(Update 17-07-2006 new formula coming soon - thank you "NoRemorse")
With that being said, I researched the different pulleys that are available for the Cobalt SS/SC and I decided to go with the 3 inch ZZP modular Pulley. ZZPerformance is a long time performance parts manufacturer for the Grand Prix GTP, they have plenty of experience building pulleys for the Eaton supercharger, and they have established a great reputation. They manufactured a modular pulley specific for the Cobalt SS/SC that can go as low as 2.6 inch, without needing to grind the Supercharger nozzle. This, and the rugged construction of the pulley, made my choice very clear.
How much of a power gain can we expect from the added Boost of the 3 inch pulley? For every decrease in pulley size of 0.1 inch, it equals to approximately 0.9-1 PSI (Pound Square Inch) of additional force fed air. The OEM pulley being 3.3 inch, going down to a 3 inch pulley means a gain of 2.5 PSI. On a Supercharged/Intercooled application like the Cobalt SS/SC, each PSI is equal to approximately 4-6 HP and 6-8 ft-torque, so 2.5PSI x 4 HP = 10 HP gain and 15 Ft-Pounds.
Since all the specifics have been identified, it’s time to discuss the installation process. With the help of the ZZP GEN2 Pulley Puller, the whole install took approximately two hours.
Click on the link to view my “How to Install:”
Now that the pulley has been installed, it was once again time to hit the Dyno. For accuracy purposes, I went to the same Dyno (KVR Performance, Ottawa). To prevent the chance of detonation, I decided to fill my tank with SUNOCO 94 Octane Gas. Edwin (Dyno Tech) and I decided that it would be best if the car was taken to a lower RPM range, as a Wideband Air Fuel Ratio Gauge had not yet been installed in my car. Edwin also mentioned that the car’s horsepower curve was still climbing; however, he shut her down early for safety purposes.
To view the results of the Dyno sheets, please click on the following links:
Baseline: Dyno run 2005 Cobalt SS/SC , 30 C˚ outside temp, 78% humidity, 90-106 C˚ coolant temp, 91 Octane Pump Gas.
194 HP / 183 ft-torque@5891RPM - Mustang DYNO
(Dyno done on June 22, 2006)
BASELINE:
Sheet 1: Dyno run 2005 Cobalt SS/SC with AEM intake, 30 C˚ outside temp, 78% humidity, 90-106 C˚ coolant temp, 91 Octane Pump Gas.
202 HP / 189 ft-torque@5891RPM - Mustang DYNO
(Dyno done on June 22, 2006)
SHEET 1:
Sheet 2: Dyno run#1 2005 Cobalt SS/SC, AEM intake, 3” ZZP pulley,36 C˚ outside temp, 90% humidity, 90-106 C˚ coolant temp, 94 Octane Pump Gas.
201 HP / 204 ft-torque@5200RPM - Mustang DYNO
(Dyno done on July 11, 2006)
SHEET 2:
For comparison purposes, Jamie (BLKSS), a member on this site, Dyno’d his Cobalt SS/SC at the same Mustang Dyno Shop. Jamie’s SS has a stock OEM air intake box and a GM Stage 2, which also uses a 3 inch pulley. His results on the Dyno were 222 HP / 194 ft-torque@7000RPM.
If you were to analyze the results of my latest addition, you would notice that its biggest improvement is definitely the torque in the low RPM range. In the past, the boost would build up to a maximum of 80 KPA / 12 PSI, whereas now, the boost increases much quicker to reach a maximum of 100 KPA / 14.8 PSI at WOT (Wide Open Throttle). It should also be mentioned that your aftermarket intake will now be somewhat louder.
For those who are wondering, I didn’t obtain any belt slippage with the 3 inch pulley. If you plan on upgrading to a smaller pulley, you will need to either purchase a smaller belt or an adjustable tensioner. This is exactly what I plan to do in the near future. In fact, my philosophy on adding power is quite simple: just take your time and do it one step at a time! Doing this will provide you with the opportunity to really enjoy each power increase, and to make sure that the upgrade actually results in an increase in power.
Stay tuned for my next “Full review/ How to Install”. I’m hoping for my next power increases to be spawned from:
1) Performance Package from ZZP:
• 42# Lucas Injectors
• ZZP 2.6 Inch Pulley
• ZZP Adjustable Tensioner
• HP tuners and lots of Dyno time
• AEROFORCE interceptor gauge / Wide Band O2 Sensor
• 2 Step colder NGK plugs
2) 3” JBP Vortex Stainless Steel Exhaust (At this point, the stock exhaust will start showing signs of being restrictive.)
Finally, thank you, ZZP, for bringing us Cobalt owners such great products. I truly enjoyed my drive home from the Dyno with my newest modification, as I realized that I am now one step closer to achieving my goal of owning the meanest and beastliest Cobalt SS/SC known to man. Any challengers?
You can purchase the Modular Pulleys and purchase or rent the GEN2 Pulley Puller directly from ZZPerformance, right here on cobaltss.net.
Denny Medeiros is also author of:
THE COBALT SS/SC: TIME TO BREATHE!
The Cobalt SS/SC: Traction-less no more!
A DREAM COME TRUE: The Supercharged Chevy Cobalt SS.
By: Denny Medeiros, Cobaltss.net
You might have read my last review, where you learned that freeing up the intake did wonders in helping the LSJ Engine breathe better. Now it’s time to step it up a notch, with some added Boost!
According to calculations, the stock (34 lb/hr) injectors on the Cobalt SS/SC can still provide enough fuel for another 30 HP over factory at 80% duty cycle. Here is the formula:
(Update 17-07-2006 new formula coming soon - thank you "NoRemorse")
With that being said, I researched the different pulleys that are available for the Cobalt SS/SC and I decided to go with the 3 inch ZZP modular Pulley. ZZPerformance is a long time performance parts manufacturer for the Grand Prix GTP, they have plenty of experience building pulleys for the Eaton supercharger, and they have established a great reputation. They manufactured a modular pulley specific for the Cobalt SS/SC that can go as low as 2.6 inch, without needing to grind the Supercharger nozzle. This, and the rugged construction of the pulley, made my choice very clear.
How much of a power gain can we expect from the added Boost of the 3 inch pulley? For every decrease in pulley size of 0.1 inch, it equals to approximately 0.9-1 PSI (Pound Square Inch) of additional force fed air. The OEM pulley being 3.3 inch, going down to a 3 inch pulley means a gain of 2.5 PSI. On a Supercharged/Intercooled application like the Cobalt SS/SC, each PSI is equal to approximately 4-6 HP and 6-8 ft-torque, so 2.5PSI x 4 HP = 10 HP gain and 15 Ft-Pounds.
Since all the specifics have been identified, it’s time to discuss the installation process. With the help of the ZZP GEN2 Pulley Puller, the whole install took approximately two hours.
Click on the link to view my “How to Install:”
Now that the pulley has been installed, it was once again time to hit the Dyno. For accuracy purposes, I went to the same Dyno (KVR Performance, Ottawa). To prevent the chance of detonation, I decided to fill my tank with SUNOCO 94 Octane Gas. Edwin (Dyno Tech) and I decided that it would be best if the car was taken to a lower RPM range, as a Wideband Air Fuel Ratio Gauge had not yet been installed in my car. Edwin also mentioned that the car’s horsepower curve was still climbing; however, he shut her down early for safety purposes.
To view the results of the Dyno sheets, please click on the following links:
Baseline: Dyno run 2005 Cobalt SS/SC , 30 C˚ outside temp, 78% humidity, 90-106 C˚ coolant temp, 91 Octane Pump Gas.
194 HP / 183 ft-torque@5891RPM - Mustang DYNO
(Dyno done on June 22, 2006)
BASELINE:
Sheet 1: Dyno run 2005 Cobalt SS/SC with AEM intake, 30 C˚ outside temp, 78% humidity, 90-106 C˚ coolant temp, 91 Octane Pump Gas.
202 HP / 189 ft-torque@5891RPM - Mustang DYNO
(Dyno done on June 22, 2006)
SHEET 1:
Sheet 2: Dyno run#1 2005 Cobalt SS/SC, AEM intake, 3” ZZP pulley,36 C˚ outside temp, 90% humidity, 90-106 C˚ coolant temp, 94 Octane Pump Gas.
201 HP / 204 ft-torque@5200RPM - Mustang DYNO
(Dyno done on July 11, 2006)
SHEET 2:
For comparison purposes, Jamie (BLKSS), a member on this site, Dyno’d his Cobalt SS/SC at the same Mustang Dyno Shop. Jamie’s SS has a stock OEM air intake box and a GM Stage 2, which also uses a 3 inch pulley. His results on the Dyno were 222 HP / 194 ft-torque@7000RPM.
If you were to analyze the results of my latest addition, you would notice that its biggest improvement is definitely the torque in the low RPM range. In the past, the boost would build up to a maximum of 80 KPA / 12 PSI, whereas now, the boost increases much quicker to reach a maximum of 100 KPA / 14.8 PSI at WOT (Wide Open Throttle). It should also be mentioned that your aftermarket intake will now be somewhat louder.
For those who are wondering, I didn’t obtain any belt slippage with the 3 inch pulley. If you plan on upgrading to a smaller pulley, you will need to either purchase a smaller belt or an adjustable tensioner. This is exactly what I plan to do in the near future. In fact, my philosophy on adding power is quite simple: just take your time and do it one step at a time! Doing this will provide you with the opportunity to really enjoy each power increase, and to make sure that the upgrade actually results in an increase in power.
Stay tuned for my next “Full review/ How to Install”. I’m hoping for my next power increases to be spawned from:
1) Performance Package from ZZP:
• 42# Lucas Injectors
• ZZP 2.6 Inch Pulley
• ZZP Adjustable Tensioner
• HP tuners and lots of Dyno time
• AEROFORCE interceptor gauge / Wide Band O2 Sensor
• 2 Step colder NGK plugs
2) 3” JBP Vortex Stainless Steel Exhaust (At this point, the stock exhaust will start showing signs of being restrictive.)
Finally, thank you, ZZP, for bringing us Cobalt owners such great products. I truly enjoyed my drive home from the Dyno with my newest modification, as I realized that I am now one step closer to achieving my goal of owning the meanest and beastliest Cobalt SS/SC known to man. Any challengers?
You can purchase the Modular Pulleys and purchase or rent the GEN2 Pulley Puller directly from ZZPerformance, right here on cobaltss.net.
Denny Medeiros is also author of:
THE COBALT SS/SC: TIME TO BREATHE!
The Cobalt SS/SC: Traction-less no more!
A DREAM COME TRUE: The Supercharged Chevy Cobalt SS.
Last edited by denny; 07-17-2006 at 12:48 PM.
07-13-2006, 08:22 PM
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Originally Posted by sunfirejoe
wow i didnt expect a hp loss, ohh well you can def see the gains in torque which is nice
So I think another 6-8 HP might a been possible with an additional 700RPM.
07-13-2006, 08:54 PM
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Originally Posted by sunfirejoe
wow i didnt expect a hp loss, ohh well you can def see the gains in torque which is nice
07-13-2006, 08:56 PM
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Originally Posted by bluedev1l
Yeah man...notice the other 2 runs went to 5891 rpms and the run with the pulley stopped at 5200 rpms. Nice write-up too, by the way, denny.
07-13-2006, 09:05 PM
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Originally Posted by denny
Nope no loss in HP. We stopped the Dyno at 5200RPM, the car was still making more HP.
So I think another 6-8 HP might a been possible with an additional 700RPM.
So I think another 6-8 HP might a been possible with an additional 700RPM.
07-13-2006, 09:10 PM
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Originally Posted by srt-killer
Why would you stop the dyno. Arnt you tying to see the difference with a pully and with out, its kinda hard to really compair when you don't even go to the same RPM.
"Now that the pulley has been installed, it was once again time to hit the Dyno. For accuracy purposes, I went to the same Dyno (KVR Performance, Ottawa). To prevent the chance of detonation, I decided to fill my tank with SUNOCO 94 Octane Gas. Edwin (Dyno Tech) and I decided that it would be best if the car was taken to a lower RPM range, as a Wideband Air Fuel Ratio Gauge had not yet been installed in my car. Edwin also mentioned that the car’s horsepower curve was still climbing; however, he shut her down early for safety purposes."
07-13-2006, 09:14 PM
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Originally Posted by srt-killer
Why would you stop the dyno. Arnt you tying to see the difference with a pully and with out, its kinda hard to really compair when you don't even go to the same RPM.
Makes no sense?! and you didnt take it up to redline..?
07-13-2006, 09:15 PM
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Originally Posted by denny
Read my review and you will know why
"Now that the pulley has been installed, it was once again time to hit the Dyno. For accuracy purposes, I went to the same Dyno (KVR Performance, Ottawa). To prevent the chance of detonation, I decided to fill my tank with SUNOCO 94 Octane Gas. Edwin (Dyno Tech) and I decided that it would be best if the car was taken to a lower RPM range, as a Wideband Air Fuel Ratio Gauge had not yet been installed in my car. Edwin also mentioned that the cars horsepower curve was still climbing; however, he shut her down early for safety purposes."
"Now that the pulley has been installed, it was once again time to hit the Dyno. For accuracy purposes, I went to the same Dyno (KVR Performance, Ottawa). To prevent the chance of detonation, I decided to fill my tank with SUNOCO 94 Octane Gas. Edwin (Dyno Tech) and I decided that it would be best if the car was taken to a lower RPM range, as a Wideband Air Fuel Ratio Gauge had not yet been installed in my car. Edwin also mentioned that the cars horsepower curve was still climbing; however, he shut her down early for safety purposes."
07-13-2006, 09:35 PM
#11
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Originally Posted by SS_SC_Cobalt
denny the dyno didnt have an a/f meter?
Edwin is the only certified tech at that shop that can operate the Dyno. I did not want to go to a different Dyno(We have 2 in Ottawa - Dynojet and Mustang Dyno) just so I could continue with my baseline run.
When I get my ZZPerformance package and necessary monitoring gauges and tuning tools, I will be reserving Dyno time for a few hours. So look for my next big review.
Last edited by denny; 07-13-2006 at 10:02 PM.
07-13-2006, 10:45 PM
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You might want to change the physical size of the OEM pulley it's 3.5 around in and the inside the track is 3.4 if you want to get specific. Just trying to be informative. Decent write up but how come your not keeping the gas and RPM's specific?
07-14-2006, 03:56 AM
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you could have taken it to redline no problem...i ran a 3" along with many other LSJ's on stock everything for months
oh well, i feel you, and respect that you care and take care of your car, not a lot of people do that today
nice write ups man
oh well, i feel you, and respect that you care and take care of your car, not a lot of people do that today
nice write ups man
07-14-2006, 08:06 AM
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Originally Posted by silverSS
you could have taken it to redline no problem...i ran a 3" along with many other LSJ's on stock everything for months
oh well, i feel you, and respect that you care and take care of your car, not a lot of people do that today
nice write ups man
oh well, i feel you, and respect that you care and take care of your car, not a lot of people do that today
nice write ups man
Finally someone that understands. Edwin did not want me to walk home from the dyno with a broken piston in my hand.
07-14-2006, 08:24 AM
#19
Originally Posted by sunfirejoe
wow i didnt expect a hp loss, ohh well you can def see the gains in torque which is nice
07-14-2006, 09:40 AM
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nice write up, thank you!
obviously a few people here don't understand your cautiousness...next time you dyno and are able to bring it all the way to red line, let us know what the AF is, I would wager to say it will be right on since GM loves to make their car run pig rich at WOT on top...
thanks again for taking the time to do a write up...
obviously a few people here don't understand your cautiousness...next time you dyno and are able to bring it all the way to red line, let us know what the AF is, I would wager to say it will be right on since GM loves to make their car run pig rich at WOT on top...
thanks again for taking the time to do a write up...
07-14-2006, 09:59 AM
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Denny,
I noticed you where running 94 Octane. Is there a reason why you are running a higher octane? I know with the stock injectors will take as little as 87-91 and or higher, but seeing as you haven't upgraded the ECU or put the big injectors in I wonder if the numbers where scewed a little bit. I know you didn't push it to redline but it would be intresting to see what you could do with 91 or even 87?
Joey
I noticed you where running 94 Octane. Is there a reason why you are running a higher octane? I know with the stock injectors will take as little as 87-91 and or higher, but seeing as you haven't upgraded the ECU or put the big injectors in I wonder if the numbers where scewed a little bit. I know you didn't push it to redline but it would be intresting to see what you could do with 91 or even 87?
Joey
07-14-2006, 10:14 AM
#22
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Originally Posted by joeytroy
Denny,
I noticed you where running 94 Octane. Is there a reason why you are running a higher octane? I know with the stock injectors will take as little as 87-91 and or higher, but seeing as you haven't upgraded the ECU or put the big injectors in I wonder if the numbers where scewed a little bit. I know you didn't push it to redline but it would be intresting to see what you could do with 91 or even 87?
Joey
I noticed you where running 94 Octane. Is there a reason why you are running a higher octane? I know with the stock injectors will take as little as 87-91 and or higher, but seeing as you haven't upgraded the ECU or put the big injectors in I wonder if the numbers where scewed a little bit. I know you didn't push it to redline but it would be intresting to see what you could do with 91 or even 87?
Joey
The reason why I decided to run 94 Octane was to prevent the chances of detonation. Since I dont have the monitoring tools(Next week I will have them all). Detonation, which can be very damaging to your engine, occurs when the octane rating of the fuel isn't high enough to handle the heat and pressure. One way to prevent detonation is to use a higher octane fuel. The octane rating of a motor fuel is a measure of its detonation resistance. The octane that's posted on the filling station pump is "pump octane," which is an average of something called "research" and "motor" octane ratings (which are two different laboratory methods of measuring octane). The higher the pump octane number, the better able the fuel is to resist detonation. I will go down to 91 as soon as I can monitor my car.
I will bring back some new numbers from the dyno as well as AFR and knock values for all of you to read.
07-14-2006, 10:17 AM
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Originally Posted by NightmareRacing
nice write up, thank you!
obviously a few people here don't understand your cautiousness...next time you dyno and are able to bring it all the way to red line, let us know what the AF is, I would wager to say it will be right on since GM loves to make their car run pig rich at WOT on top...
thanks again for taking the time to do a write up...
obviously a few people here don't understand your cautiousness...next time you dyno and are able to bring it all the way to red line, let us know what the AF is, I would wager to say it will be right on since GM loves to make their car run pig rich at WOT on top...
thanks again for taking the time to do a write up...
Thanks! Yes, I would not be surprise if that is the case. But better safe then sorry, right! Happy to see some people appreciate my work that I bring to the forum
07-14-2006, 12:26 PM
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Everytime you have a great write up like this, I end up spending more money. How much did it cost you for the ZZP Setup you got?
But, once again, Great Write Up.
-Jordan-
But, once again, Great Write Up.
-Jordan-
07-14-2006, 12:55 PM
#25
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Originally Posted by Cobalt_SSTuner
Everytime you have a great write up like this, I end up spending more money. How much did it cost you for the ZZP Setup you got?
But, once again, Great Write Up.
-Jordan-
But, once again, Great Write Up.
-Jordan-
Thank you. The ZZP modular pulley was $99.99U.S!!If you want to buy other size pulley's their $49.99U.S each.