superchargers
#21
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I like the punch of the roots blower. I had a Vortech V4 540ci engine and hated it. No power under 4000 rpm. I do not enjoy waiting for an engine to boost up. In my application 4000 is 100 mph. I would fall asleep waiting for the boost. KE was having problems with the 1700 engine with the centrifugal setup. Real dog down low. But the latest is they seem to have found more power on the low end by using a new type supercharger. Dual stage? Not sure what they did but my friend who has them was really upset with the first version and now seems to be happy with the more broad power band after KE reworked them.
#22
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Hi Brad:
Sorry to hear about your experience with the Vortech V-4. It's a good entry level 700 HP system. All I can say is that when we convert the Vortech EFI system to our intercooler arrangement we see 800 HP on the dyno and no complaints about low RPM performance. This comment is based on our experience with engines using stock heads and cams, with vees operating up to 100 mph, and with cats up to 125 mph.
The trouble seems to start when you move above 1000 HP. We're used to the big intake ports and big cams that work with Roots blowers and we expect them to work with centrifugals and/or turbos. Matching the right compressor size to the job is also important. Mr. Eickert, Mr. Hofstetter and others are blazing trails here and kudos to them all. With help from Mr. D'Annibale we are doing some blazing too.
With the advent of 150+ mph poker run boats, the difficulty of running a one gear boat at low RPM is compounded. Yes, positive displacement blowers can manage this situation, but centrifugals and turbos can make more power, so don't be surprised if 2-speed transmissions start showing up. The advantages in dock manners, idling speed and ultimate top speed make it worth the effort to solve the problem that way.
Love your choice of boats and have no problems with your choice of blower. Maybe see you in Sarasota.
Tom
Sorry to hear about your experience with the Vortech V-4. It's a good entry level 700 HP system. All I can say is that when we convert the Vortech EFI system to our intercooler arrangement we see 800 HP on the dyno and no complaints about low RPM performance. This comment is based on our experience with engines using stock heads and cams, with vees operating up to 100 mph, and with cats up to 125 mph.
The trouble seems to start when you move above 1000 HP. We're used to the big intake ports and big cams that work with Roots blowers and we expect them to work with centrifugals and/or turbos. Matching the right compressor size to the job is also important. Mr. Eickert, Mr. Hofstetter and others are blazing trails here and kudos to them all. With help from Mr. D'Annibale we are doing some blazing too.
With the advent of 150+ mph poker run boats, the difficulty of running a one gear boat at low RPM is compounded. Yes, positive displacement blowers can manage this situation, but centrifugals and turbos can make more power, so don't be surprised if 2-speed transmissions start showing up. The advantages in dock manners, idling speed and ultimate top speed make it worth the effort to solve the problem that way.
Love your choice of boats and have no problems with your choice of blower. Maybe see you in Sarasota.
Tom
#23
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Airtime: Talk to Dean Nickerson; he makes 1000 HP with our setup using one of his blowthrough carbs and 10 psi. Another customer made the same HP using EFI and 10 psi. They were both at 8.25:1 CR. Your compression ratio is too high for that much boost. We have put 3-4 psi on top of that much CR but it's an expensive way to make a little HP. What heads and cam are you using?
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#26
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Airtime: Talk to Dean Nickerson; he makes 1000 HP with our setup using one of his blowthrough carbs and 10 psi. Another customer made the same HP using EFI and 10 psi. They were both at 8.25:1 CR. Your compression ratio is too high for that much boost. We have put 3-4 psi on top of that much CR but it's an expensive way to make a little HP. What heads and cam are you using?
#27
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No, I put my shortie lowers on Friday night. When I finished, I was give out and I kept thinking something doesn't look right??? I was missing the cavitation plates that bolt to the uppers. So, I have a set on the way......but I didn't figure I could get out of the hole without them....Smith's old 388 lost both of them one day up at the hill and we could not get it on plane!