SuperVerde's Mega Coast to Coast Road Trip summary
Posted: Sun Nov 27, 2005 10:05 am
Now that my dad's Milano "SuperVerde" has completed its Mega road trip I though I would write a quick summary here. Overall it went quite well, we did learn about a couple design problems as a result of this trip which we worked out right away. More on that later.
We installed the Supercharger on a Sunday afternoon. For a supercharged 3.0 larger injectors are required for any meaningfull increase in power but I didn't have any in stock. So we set it up with about 2 pounds of boost which is about all the stock size injectors can support. Two pounds of boost does very little for power. It adds enough air for about a 25 horsepower increase but it requires the supercharger to operate far out of its ideal range so the reality is probably about a 15 horsepower gain. Not really worth it, but since I couldn't get the big injectors in time for the first leg that's how the car left home.
The first leg was to Denver Colorado and then up to Kimball Nebraska. This was all flat land driving and the car performed very well. My dad then drove to the East Coast which is where he discovered a small flaw in the kit. When crossing the Appalachian mountains he found that the supercharger would engage way too easily when going up hill. The on/off function works off vacuum and when going up hill vacuum decreases either as a result of the car slowing down or an increase in throttle. This drop in vacuum would turn the supercharger on on almost all the uphill segments. Since the car doesn't need the boost the throttle would not be open much so all the supercharger ends up doing is consuming fuel to compress the air between itself and the throttle plate. Of course with ultra low boost this wasn't really a big deal but I knew I would have to take care of it.
My dad visited the nice folks at International Auto Parts in Virginia. He was very impressed with thier operation and gave a ride to his contact there who has helped a lot with the car. At this point of course it still only had 2 pounds of boost.
Dad then drove the car back to Dallas. My family and I then borrowed the car and took it down to the Italian Car festival in Dallas. It was an incredible show with a lot of fantastic stuff. We had a great time and the car got a lot of attention. I got to meet some nice folks from this forum and the Alfabb and had a great time.
Shortly after the show the big (Stage 2) injectors showed up so we put them in, bumped the boost up to a very conservative 5 pounds and ran the car on the dyno. It put down 205 at the wheels which is about a 34% gain over stock, about right since we added 33% more air. (That's about 250 flywheel horsepower using the commonly accepted but unrealistic 18% loss rule) The torque curve was good and flat although not as high as I would have liked due to a rich mixture below 5000 rpm. No time to deal with that though since the car had to go to the west coast right away. I should point out that we intended this motor to handle about 8 pounds of boost but since California only has 91 octane fuel we figured we should be really conservative and keep it down to 5 psi.
For this leg of the trip we bumped the idle speed up to 1200 rpm because of another minor flaw we discovered. When shifting with boost ON, the throttle plate would close faster then the supercharger's shut off valve could react. This resulted in pressure spikes in the intake pipe high enough to blow apart the 50 psi rated couplers! Hmm, this never happened with my GTV6. The reason it didn't happen on my car is that 99% of its testing was done with the old style V-Belt. Well, the V-Belt can't spike the boost that highs because it will slip first. I never thought of that during initial testing but the V-Belt's lack of grip prevented any sort of boost spikes. Clearly because the 6 rib doesn't slip I needed a way to reduce those pressure spikes, so I simply cracked the throttle plate open a bit. That allows enough pressure to escape through the throttle body during upshifts that everything works out. However my dad took it upon himself to set it at 1500 rpm because he was so worried about blowing a coupler a hundred miles from anywhere. For those of you not familiar with the Western United States, I can tell you there are vast areas of NOTHING. You don't want a break down out there.
Other then having a high idle speed and the fact that the supercharger would turn on going uphill the car performed flawlessly. No break downs, no part failures, no pinging on California's lousy 91 octane fuel.
My dad met with a group of People from this site including Nizam and Zamani up in the bay area. My dad had a great time. He gave a couple people rides in the car and it performed just fine. However his tach chose this moment to crap out so he kept hitting the 6800 rpm limiter (the 5800 rpm limiter has been removed from this car). He then drove the car back down to Southern California and met up with some other great folks, including a designer of a new Milano body kit I have to keep the details secret, but the design looks incredible).
Next my dad drove back to Texas where we installed secondary ON/OFF valve to solve the uphill and idle speed issue. This worked perfectly. This not only solved both of these problems but part throttle boost on operations are now quieter. It also smoothed out the supercharger's ON/OFF transitions to the point where it's now near OEM smooth! This was a huge improvment. We set the idle speed at 700 RPM and drove around trying to blow a coupler. We couldn't, the new valve works perfectly.
After only being back for two days my dad drove to Ft Collins Colorado where he is right now. The 700 RPM idle speed is very pleasant and the car is performing perfectly.
I consider this trip to have been very succesfull. A lot of people got the see the kit. It's reliability is certainly proven (who else bolts a kit on and drives Coast to Coast the next day?) The only failure on the whole trip was the tachometer. My dad got to meet a lot of nice folks and had a fun time. Perhaps most importantly the uphill flaw was revealed which I would never have discoverd driving around Texas. When my dad gets back home again this Tueday we plan to add a little more power to the car via slightly more boost and a fuel curve change. I also need to get the new solid dishcarge pipes and secondary valves shipped out to everyone who bought kit. That's a free upgrade as I should have included it in the first place.
That's all for now. Watch for the New dyno results. Power will be going up.
We installed the Supercharger on a Sunday afternoon. For a supercharged 3.0 larger injectors are required for any meaningfull increase in power but I didn't have any in stock. So we set it up with about 2 pounds of boost which is about all the stock size injectors can support. Two pounds of boost does very little for power. It adds enough air for about a 25 horsepower increase but it requires the supercharger to operate far out of its ideal range so the reality is probably about a 15 horsepower gain. Not really worth it, but since I couldn't get the big injectors in time for the first leg that's how the car left home.
The first leg was to Denver Colorado and then up to Kimball Nebraska. This was all flat land driving and the car performed very well. My dad then drove to the East Coast which is where he discovered a small flaw in the kit. When crossing the Appalachian mountains he found that the supercharger would engage way too easily when going up hill. The on/off function works off vacuum and when going up hill vacuum decreases either as a result of the car slowing down or an increase in throttle. This drop in vacuum would turn the supercharger on on almost all the uphill segments. Since the car doesn't need the boost the throttle would not be open much so all the supercharger ends up doing is consuming fuel to compress the air between itself and the throttle plate. Of course with ultra low boost this wasn't really a big deal but I knew I would have to take care of it.
My dad visited the nice folks at International Auto Parts in Virginia. He was very impressed with thier operation and gave a ride to his contact there who has helped a lot with the car. At this point of course it still only had 2 pounds of boost.
Dad then drove the car back to Dallas. My family and I then borrowed the car and took it down to the Italian Car festival in Dallas. It was an incredible show with a lot of fantastic stuff. We had a great time and the car got a lot of attention. I got to meet some nice folks from this forum and the Alfabb and had a great time.
Shortly after the show the big (Stage 2) injectors showed up so we put them in, bumped the boost up to a very conservative 5 pounds and ran the car on the dyno. It put down 205 at the wheels which is about a 34% gain over stock, about right since we added 33% more air. (That's about 250 flywheel horsepower using the commonly accepted but unrealistic 18% loss rule) The torque curve was good and flat although not as high as I would have liked due to a rich mixture below 5000 rpm. No time to deal with that though since the car had to go to the west coast right away. I should point out that we intended this motor to handle about 8 pounds of boost but since California only has 91 octane fuel we figured we should be really conservative and keep it down to 5 psi.
For this leg of the trip we bumped the idle speed up to 1200 rpm because of another minor flaw we discovered. When shifting with boost ON, the throttle plate would close faster then the supercharger's shut off valve could react. This resulted in pressure spikes in the intake pipe high enough to blow apart the 50 psi rated couplers! Hmm, this never happened with my GTV6. The reason it didn't happen on my car is that 99% of its testing was done with the old style V-Belt. Well, the V-Belt can't spike the boost that highs because it will slip first. I never thought of that during initial testing but the V-Belt's lack of grip prevented any sort of boost spikes. Clearly because the 6 rib doesn't slip I needed a way to reduce those pressure spikes, so I simply cracked the throttle plate open a bit. That allows enough pressure to escape through the throttle body during upshifts that everything works out. However my dad took it upon himself to set it at 1500 rpm because he was so worried about blowing a coupler a hundred miles from anywhere. For those of you not familiar with the Western United States, I can tell you there are vast areas of NOTHING. You don't want a break down out there.
Other then having a high idle speed and the fact that the supercharger would turn on going uphill the car performed flawlessly. No break downs, no part failures, no pinging on California's lousy 91 octane fuel.
My dad met with a group of People from this site including Nizam and Zamani up in the bay area. My dad had a great time. He gave a couple people rides in the car and it performed just fine. However his tach chose this moment to crap out so he kept hitting the 6800 rpm limiter (the 5800 rpm limiter has been removed from this car). He then drove the car back down to Southern California and met up with some other great folks, including a designer of a new Milano body kit I have to keep the details secret, but the design looks incredible).
Next my dad drove back to Texas where we installed secondary ON/OFF valve to solve the uphill and idle speed issue. This worked perfectly. This not only solved both of these problems but part throttle boost on operations are now quieter. It also smoothed out the supercharger's ON/OFF transitions to the point where it's now near OEM smooth! This was a huge improvment. We set the idle speed at 700 RPM and drove around trying to blow a coupler. We couldn't, the new valve works perfectly.
After only being back for two days my dad drove to Ft Collins Colorado where he is right now. The 700 RPM idle speed is very pleasant and the car is performing perfectly.
I consider this trip to have been very succesfull. A lot of people got the see the kit. It's reliability is certainly proven (who else bolts a kit on and drives Coast to Coast the next day?) The only failure on the whole trip was the tachometer. My dad got to meet a lot of nice folks and had a fun time. Perhaps most importantly the uphill flaw was revealed which I would never have discoverd driving around Texas. When my dad gets back home again this Tueday we plan to add a little more power to the car via slightly more boost and a fuel curve change. I also need to get the new solid dishcarge pipes and secondary valves shipped out to everyone who bought kit. That's a free upgrade as I should have included it in the first place.
That's all for now. Watch for the New dyno results. Power will be going up.