Will the AFR 357cc heads work well???
04-23-2004, 09:50 PM
#21
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I love it when you put the technical spin on the threads with absolute facts, Tomcat, you are the man. I agree with Tomcat, crank up the boost and buy an R-tech cooler.
04-23-2004, 11:20 PM
#22
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Solid roller cam in the 250/255 .650/.650 range should be about right.
Greeat big header primary tubes. Dry tailpipes.
Don't need to spin it much over 6,000.
110 octane should let you spin over 12 pounds of boost if you run a high flow cooler, would be my guess.
Keep us informed.
Greeat big header primary tubes. Dry tailpipes.
Don't need to spin it much over 6,000.
110 octane should let you spin over 12 pounds of boost if you run a high flow cooler, would be my guess.
Keep us informed.
04-23-2004, 11:58 PM
#23
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This is the Tech section, let the experiment begin!
Bigger, better intercoolers are one way to improve the overall results, but big heads, cams and exhaust pipes are another, since they reduce the restriction faced by the blower. They also lead you to higher RPM which certainly helps make HP. As a last resort there's race gas.
I like the sound of the engine Beak Boater described. Had to make 650 HP on its on and probably made 850 HP with very reasonable boost. Hydraulic roller, 5600 RPM...beautiful. Of course, I would use a different blower and intercooler and make 1000 HP.
Bigger, better intercoolers are one way to improve the overall results, but big heads, cams and exhaust pipes are another, since they reduce the restriction faced by the blower. They also lead you to higher RPM which certainly helps make HP. As a last resort there's race gas.
I like the sound of the engine Beak Boater described. Had to make 650 HP on its on and probably made 850 HP with very reasonable boost. Hydraulic roller, 5600 RPM...beautiful. Of course, I would use a different blower and intercooler and make 1000 HP.
04-24-2004, 05:50 AM
#24
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Tomcat
Not knowing the true efficiency of the core, plumbing frictional losses and actual hp loss of turning the blower, (at least to start with) is it safe to use the above 100% gas law calculation and subtract say...15% to give you a "close to reality" hp estimate?
I say 15% because the cooler is typically 90%, add another 5% for blower and frictional loss in the average centrifugal SC setup.
DAVE
Not knowing the true efficiency of the core, plumbing frictional losses and actual hp loss of turning the blower, (at least to start with) is it safe to use the above 100% gas law calculation and subtract say...15% to give you a "close to reality" hp estimate?
I say 15% because the cooler is typically 90%, add another 5% for blower and frictional loss in the average centrifugal SC setup.
DAVE
04-24-2004, 10:37 AM
#25
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I think 10% off the ideal calculation would be close for most centrifugal setups. Tthe supercooler setup is about 3.5% off the ideal. These figures are based on dyno tests we have done on blowthrough carb systems, and my observations of the number of elbows I have counted in Procharger installations.
Included in these numbers is the cooling provided by the evaporating fuel. I can believe that this has some effect on intake air density on a blowthrough carb system, but probably not much with port injection. I have heard people say that the carb systems will make a little more power; this may be why.
I hope your project is coming together. I wish I could help out more with it.
Tom
Included in these numbers is the cooling provided by the evaporating fuel. I can believe that this has some effect on intake air density on a blowthrough carb system, but probably not much with port injection. I have heard people say that the carb systems will make a little more power; this may be why.
I hope your project is coming together. I wish I could help out more with it.
Tom
04-24-2004, 12:48 PM
#26
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Tom,
Dont worry. You helped plenty. When talking to you on the phone you said a few things that triggered a few ideas that wound up coming together. I'll be getting wet within the next 2 weeks.
Thanks again for your help and info.
DAVE
Dont worry. You helped plenty. When talking to you on the phone you said a few things that triggered a few ideas that wound up coming together. I'll be getting wet within the next 2 weeks.
Thanks again for your help and info.
DAVE
05-04-2004, 11:14 AM
#27
ZT260,
I just built some motors similar to yours so maybe this will help. Mine are 598ci. 4.5 stroke 4.6 bore 1471 blowers with intercoolers. solid roller cam.Crane #r-260/390-2s-10, which was a Paul Pfaff purchase.Brodix 2X heads with no work done at all. The motors made 1030 HP @ 6400 and 1000 ft/lbs of torque. this was on 91 oct. with 9# of boost and comp of 8.5. Just so you Know it was done at Boyd racing engines in Ok. Which builds all of Big Thunders motors. I am a little concerned about the boost and comp. but Louis said as long as i run 93 oct ,which I always do, I should be fine. Hope this helps, just thought I would give you some real #s to go along with all the theories.
I just built some motors similar to yours so maybe this will help. Mine are 598ci. 4.5 stroke 4.6 bore 1471 blowers with intercoolers. solid roller cam.Crane #r-260/390-2s-10, which was a Paul Pfaff purchase.Brodix 2X heads with no work done at all. The motors made 1030 HP @ 6400 and 1000 ft/lbs of torque. this was on 91 oct. with 9# of boost and comp of 8.5. Just so you Know it was done at Boyd racing engines in Ok. Which builds all of Big Thunders motors. I am a little concerned about the boost and comp. but Louis said as long as i run 93 oct ,which I always do, I should be fine. Hope this helps, just thought I would give you some real #s to go along with all the theories.
