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high sierra posted 02-20-2005 10:49 PM ET (US)
What pitch prop is best at Sacramento Delta (sea level) for a 60-HP four-stroke Yamaha on a classic 15-foot Boston Whaler hull? All mine are for high altitude. Thanks.
jimh posted 02-21-2005 10:40 AM ET (US)
The notion that your need a different propeller for running at sea level versus when running at altitude is based on the assumption that the engine horsepower will be lower at altitude. This assumption is based on having an engine fuel induction system which is not compensated for barometric pressure. Many modern engines which have electronic fuel injection have barometric pressure sensors in them, and the engine control module will correct for changes in atmospheric pressure (such as those that occur with increasing altitude) by adjusting the fuel/air mixture ratio.
If your engine has such compensation, it should produce the same horsepower at altitude as at sea level, and thus you probably wont need to change propellers.
Older engines that use a carburetor make adjustments to the fuel/air mixture by changing the size of the fuel inlets ("jets") in the carburetor. If your engine has had its carburetor adjusted for running at altitude, when you change to sea level it may not run as well. If the carburetor is using the stock jets, it may run better at sea level, since that is most likely what it was set for at the factory. If that is the case, you may have slightly more horsepower available.
It is somewhat difficult to predict what propeller will be "best" for your boat and motor at sea level because we don't know:
--if your motor is EFI or carburetor
--if your motor is carburetor, was it adjusted for altitude or sea level
--if your motor was adjusted to run at altitude, what altitude was it adjusted for;
--what propeller you use now
If you do have more horsepower available at sea level that you are accustomed to at altitude, it may be enough to warrant an increase in the pitch of the propeller.
Richard Quinlivan posted 02-21-2005 11:01 AM ET (US)
Jim
I beg to differ. Although a modern computer controlled engine can indeed adjust the mixture properly for the lower air density it can't do anything about lower air density. The only way to accomplish altitude compensation to maintain horsepower is to supercharge or turbocharge the engine as in aircraft engines. The Verado will do just fine.
Dick Quinlivan
kglinz posted 02-21-2005 11:16 AM ET (US)
I don't disagree with you very often, but here I do. The loss of power at altitude is a fact, on normally asperated engines. The numbers are given as 3% or 4% of loss per thousand feet. Changing the fuel as altitude changes simply keeps the fuel/air ratio correct by reducing the fuel. High altitude is where Verados will "shine"...... http://www.bassandwalleyeboats.com/site_page_897/article_page_175.cfm
Kemp Lindsey
high sierra posted 02-21-2005 12:02 PM ET (US)
I'm going to the rendezvous, I hope, on the Sacramento Delta in May. There is a huge difference in the running of an outboard due to altitude. Both Quinlivan and Kglinz are dead on in this situation. The Verado is the perfect answer. Supercharged. It's difficult for the flatlanders (no disrespect) to understand why their motors run so poorly up here. Prop selection is more important than FI when faced with thinner air. All my props are reworked to work fairly well at altitude but seriously over rev at sea level. Still need to know what pitch is effective at sea level with a 60 FI on a 15.4 . Thanks to all for the opinions. high sierra
Sal DiMercurio posted 02-21-2005 12:08 PM ET (US)
If that engine is carbed & has had the jets replaced for high altitude, you will burn that engine up if run at sea level, because it will be running "FAR" to lean.
When dealing with an older engine that dosen't have a computer to adjust the air fuel mixture, the next best thing is to drop down [ at least ] 2" in pitch size in order to allow the engine to rev to an acceptable rpm.
Most DFI engines will compensate for the altitude difference, not just the super charged 4 stroke.
I've run blown or super charged 4 stroke engines [ carbed ] on lake tahoe & there's a "BIG" difference so I doubt the Verado will be any different unless it's also fuel injected.
I've found the fuel injected engines do far better than carbed.
I think the reduction in hp is more than 3 - 4 % per 1000 ft., as Tahoe is about 5,000 ft & that would be like 18 - 20% reduction in hp but the truth is, it's more like 40% loss of power.
I really couldn't tell you if the Verado is injected or carbed.
Sal
15ftlover posted 02-21-2005 12:12 PM ET (US)
High Sierra,
Sorry to hear you still have not found the right combo for your yamaha. I run a 60 hp merc 4 stroke EFI at sea level with a Stainless 10 1/4 inch x 14 inch heavily cupped 3 blade prop. It turns 6000 RPM and will carry the boat @ 41.7 WOT (1 person) with GPS. Hope this helps
Hen
Binkie posted 02-21-2005 01:04 PM ET (US)
If you run at altitude you would need to run leaner, so the air fuel mixture would be the same as at sea level. If you can turn the same rpm at sea level and at altitude, you can run the same prop, or else you need to test props so you cand run the max rpm. For years Saltan Sea in California was known as the fastest water around, and most speed records were set there. I believe its salt water which is more boyent and below sea level. Most speed attempts were made during the summer, at sunrise, when the air was cool and moist, which is what any internal combustion engine loves. I hear from California racers that it isn`t used any more, because the water is dirty and full of junk. I don`t know, I`ve never been there, but there is some fast water in Louisiana that is below sea level.
jimh posted 02-21-2005 01:26 PM ET (US)
Good points. Let's consider this:
A decrease in air density causes a decrease in horsepower. This happens no matter what caused the decrease in air density. I assume that colder air is more dense than warmer air. Thus an engine operating at an air temperatures of 40-degrees would have more horsepower than the same engine at 100-degree air temperature.
How much does the density of air change per degree versus how much does it change per 1,000 feet of altitude. With this information we could compare the affect that temperature has to the effect that altitude has.
Maybe we all need propellers for cold days and hot days, too.
Joe Kriz posted 02-21-2005 01:32 PM ET (US)
Highsierra,
I went through this a couple of years ago on a "Carbed" Evinrude engine.
The jets on a carbed engine are only changed for (High) altitudes of 5,000 feet and higher, meaning they will run lean if you take this same engine to Sea Level without changing the jets back to the original ones used for Sea Level.
(Don't confuse changing the jets slightly so this particular engine runs better at a certain altitude below 5,000 feet. Most carbed engines are slightly adjusted for optimum performance by changing the idle jets in a particular situation.)
As Sal mentions above, you could ruin the engine by running High Altitude jets at Sea Level. Don't Do It...
If your engine is EFI or DFI, then the computer will take care of the fuel/air mixture and the prop is the only thing you might need to change for optimum performance.
onlyawhaler posted 02-21-2005 01:59 PM ET (US)
Altitude is a huge factor in carb outboards. Since I have never owned a EFI or DFI I cannot comment on first hand experience.
However, here is the real life effect on an 18 Outrage with a 80s era carb Johnson 150. Most dealers in the area from that time left stock sealevel jets in the outboards. The reason is that if a carb outboard at this altitude (4500-7000ft)at the popular lakes here in Utah is tuned with high altitude jets the owner runs the risk of burning up the powerhead if it is taken and run at sea level and not remembering to change out jets. Lower altitude, more air, same fuel mixture= leaner mixture.
I have run my outrage at 6-7000 feet and then at Lake Mead down by Las Vegas which I believe is close to 1000 feet and the difference in performance is very noticable. I change from a 17 to a 19 pitch prop or I will over rev.
In talking with a few friends who are in the bass boat market, it is the same with EFI according to them. They run better with less smoking than my carb unit, but they still experience more power when boating at lower lakes vs higher lakes. Hole shots are better, acceleration is better, everything is better at lower altitude.
It is interesting to see the difference in Sea Rays, Bayliners and the local market up here vs down there anywhere. A Searay Sundancer works fine a sea level with a 5.7 GM 350 V-8, but wouuld struggle to even get on plane up here. Dealers typically max out the available horsepower options and also change out the gearcase in most instances on the outdrives to the altitude gear cases options to help out the situation.
Onlyawhaler
Jerry Townsend posted 02-21-2005 02:47 PM ET (US)
Hey guys - it is not only density - but also the atmospheric pressure - which really changes the air/fuel ratio. Density is only one part of the equation. At sea level, there will be more air drawn into the carburetor than at some higher elevation for the same engine conditions. I have not heard the 3 - 4% per thousand feet that Kemp (kglinz) quotes - but it should be in the ball-park.
And of course, should one be moving from or to a significant change in altitude - it is prudent to change the jets on your carburetor.
Also, High Sierra's question concerns the affect of altitude on the performance of the prop. There will indeed, be an altitude affect - but I suspect that any affect will be principally realized in really high performance applications where cavitation is more apt to come into play. There should be less cavitation at sea level than at a high elevation for the same rpm/power (prop). Therefore, a prop that works well at altitude should work well at sea level.
This is another "wrinkle" that has not been addressed before and my first swing through some technical stuff came up dry - I will put it on a front burner and see what I can come up with in the near future.
high sierra posted 02-21-2005 04:01 PM ET (US)
To all, the prop is just as efficient at sea level as it is at high altitude. The density of the water is the same. It is the lack of dense air, or atmospheric pressure, (the proper term , thanks Jerry )that doesn't let the engine produce the torque and horsepower. We at this height, figure 3% loss per 1000 feet and that is an understatement. As stated by Sal, it seems like a lot more power than that is lost ,and it is. The upper part of the powerband is where the torque is developed and the engine usually fails to get to that rpm due to the lack of atmospheric pressure and being overproped. The salton sea is a good example of the opposite end of the spectrum. ( Binkie is right ) The average prop has to be downsized 3 to 6 inches less pitch just to plane the boat. (thanks 15ftlover for the exact spec.) High Sierra
15ftlover posted 02-21-2005 05:14 PM ET (US)
High sierra,
Our dealer originally put a 17 inch aluminum prop on the boat and delivered it as being "ideal". They obviously made a mistake (overpropped at sea level) as we could not get above 5400-5500 RPM with the 17 inch. Let me know how you do if you can find a 3 blade SS 14 inch. I am impressed at the altitude effect, I generally feel our new motor is provides plenty of power down here in Charleston
Hen
Jerry Townsend posted 02-21-2005 07:30 PM ET (US)
High Sierra - the efficiency of the prop will be basically the same under normal operation at sea level and at an elevated altitudes. And, for all practical purposes, the density will be basically the same - though, in actuality, there will be insignificant difference - because of the different pressure and temperature.
But - a heavily loaded prop will cavitate at higher elevations, and the efficiency go to hell, whereas it would not cavitate at sea level with the same rpm/power conditions - due to the decreased pressure at the plane of the prop at an elevated altitude.
And forgetting all of this stuff - you probably can't tell the difference in the prop performance at sea level and being up in the air 5000 feet or so. ------ Jerry/Idaho
high sierra posted 02-21-2005 07:43 PM ET (US)
Jerry , where is this decreased pressure at the plane? of the prop? Are you trying to dazzle me with brilliance or baffle me with **** ****? I can be swayed with logic. High Sierra
high sierra posted 02-21-2005 07:56 PM ET (US)
Jerry, that is meant to be a funny line, from a firehouse. No harm intended. Appreciate your input. thanks
brainstormer posted 02-21-2005 08:22 PM ET (US)
just some additional data a '84 70hp Evinrude on my 17' Supersport with a 17 pitch prop got up and did ok @ 2500 ft above sealevel, but when taken to Pactola Res. in So. Dak. @ 6400' wouldn't get up on a plane for almost an 1/8th of a mile and had trouble even starting it. Next year with a 93 90hp Johnson it would get up on plane ok, but wouldn't come close to WOT rpm's, same prop. same boat. This year we'll see what a '99 115 will do come 4th of July.
Jerry Townsend posted 02-22-2005 02:21 AM ET (US)
High Sierra - no problem. The only thing I was trying to say is - the reduced atmospheric pressure at some elevated altitude would tend to induce cavitation easier than the same prop loading conditions at sea level.
But again - I doubt that anyone could really tell any difference in the performance of the prop at sea level and then at some elevated altitude. --- Jerry/Idaho
skookum point posted 02-22-2005 02:26 AM ET (US)
hi sierra,
I have owned several boats powered with 2-stroke outboards that I have trailered back and forth between Puget Sound (sea level)and Utah/Idaho mountain lakes (7000+ ft). In every case a 3" to 4" change in pitch has adequately compensated for loss of power at altitude. For example, my 15' Whaler with a 50hp OMC would turn a 17" prop at sea level but needed a 13" at 7500 ft to get the same revs.
Now I am in the process of preparing a high altitude Montauk (125hp Merc) for use at sea level. I have rejetted the carbs back to the original sizes. At 7000 ft it ran well with a 21 pitch prop. I'm betting it will turn a 24pitch at sea level. Hope that helps.
John
high sierra posted 02-22-2005 11:38 AM ET (US)
Thanks to all! High Sierra

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Author	Topic: Effect of Altitude on Propeller Choice
high sierra	posted 02-20-2005 10:49 PM ET (US) What pitch prop is best at Sacramento Delta (sea level) for a 60-HP four-stroke Yamaha on a classic 15-foot Boston Whaler hull? All mine are for high altitude. Thanks.
jimh	posted 02-21-2005 10:40 AM ET (US) The notion that your need a different propeller for running at sea level versus when running at altitude is based on the assumption that the engine horsepower will be lower at altitude. This assumption is based on having an engine fuel induction system which is not compensated for barometric pressure. Many modern engines which have electronic fuel injection have barometric pressure sensors in them, and the engine control module will correct for changes in atmospheric pressure (such as those that occur with increasing altitude) by adjusting the fuel/air mixture ratio. If your engine has such compensation, it should produce the same horsepower at altitude as at sea level, and thus you probably wont need to change propellers. Older engines that use a carburetor make adjustments to the fuel/air mixture by changing the size of the fuel inlets ("jets") in the carburetor. If your engine has had its carburetor adjusted for running at altitude, when you change to sea level it may not run as well. If the carburetor is using the stock jets, it may run better at sea level, since that is most likely what it was set for at the factory. If that is the case, you may have slightly more horsepower available. It is somewhat difficult to predict what propeller will be "best" for your boat and motor at sea level because we don't know: --if your motor is EFI or carburetor --if your motor is carburetor, was it adjusted for altitude or sea level --if your motor was adjusted to run at altitude, what altitude was it adjusted for; --what propeller you use now If you do have more horsepower available at sea level that you are accustomed to at altitude, it may be enough to warrant an increase in the pitch of the propeller.
Richard Quinlivan	posted 02-21-2005 11:01 AM ET (US) Jim I beg to differ. Although a modern computer controlled engine can indeed adjust the mixture properly for the lower air density it can't do anything about lower air density. The only way to accomplish altitude compensation to maintain horsepower is to supercharge or turbocharge the engine as in aircraft engines. The Verado will do just fine. Dick Quinlivan
kglinz	posted 02-21-2005 11:16 AM ET (US) I don't disagree with you very often, but here I do. The loss of power at altitude is a fact, on normally asperated engines. The numbers are given as 3% or 4% of loss per thousand feet. Changing the fuel as altitude changes simply keeps the fuel/air ratio correct by reducing the fuel. High altitude is where Verados will "shine"...... http://www.bassandwalleyeboats.com/site_page_897/article_page_175.cfm Kemp Lindsey
high sierra	posted 02-21-2005 12:02 PM ET (US) I'm going to the rendezvous, I hope, on the Sacramento Delta in May. There is a huge difference in the running of an outboard due to altitude. Both Quinlivan and Kglinz are dead on in this situation. The Verado is the perfect answer. Supercharged. It's difficult for the flatlanders (no disrespect) to understand why their motors run so poorly up here. Prop selection is more important than FI when faced with thinner air. All my props are reworked to work fairly well at altitude but seriously over rev at sea level. Still need to know what pitch is effective at sea level with a 60 FI on a 15.4 . Thanks to all for the opinions. high sierra
Sal DiMercurio	posted 02-21-2005 12:08 PM ET (US) If that engine is carbed & has had the jets replaced for high altitude, you will burn that engine up if run at sea level, because it will be running "FAR" to lean. When dealing with an older engine that dosen't have a computer to adjust the air fuel mixture, the next best thing is to drop down [ at least ] 2" in pitch size in order to allow the engine to rev to an acceptable rpm. Most DFI engines will compensate for the altitude difference, not just the super charged 4 stroke. I've run blown or super charged 4 stroke engines [ carbed ] on lake tahoe & there's a "BIG" difference so I doubt the Verado will be any different unless it's also fuel injected. I've found the fuel injected engines do far better than carbed. I think the reduction in hp is more than 3 - 4 % per 1000 ft., as Tahoe is about 5,000 ft & that would be like 18 - 20% reduction in hp but the truth is, it's more like 40% loss of power. I really couldn't tell you if the Verado is injected or carbed. Sal
15ftlover	posted 02-21-2005 12:12 PM ET (US) High Sierra, Sorry to hear you still have not found the right combo for your yamaha. I run a 60 hp merc 4 stroke EFI at sea level with a Stainless 10 1/4 inch x 14 inch heavily cupped 3 blade prop. It turns 6000 RPM and will carry the boat @ 41.7 WOT (1 person) with GPS. Hope this helps Hen
Binkie	posted 02-21-2005 01:04 PM ET (US) If you run at altitude you would need to run leaner, so the air fuel mixture would be the same as at sea level. If you can turn the same rpm at sea level and at altitude, you can run the same prop, or else you need to test props so you cand run the max rpm. For years Saltan Sea in California was known as the fastest water around, and most speed records were set there. I believe its salt water which is more boyent and below sea level. Most speed attempts were made during the summer, at sunrise, when the air was cool and moist, which is what any internal combustion engine loves. I hear from California racers that it isn`t used any more, because the water is dirty and full of junk. I don`t know, I`ve never been there, but there is some fast water in Louisiana that is below sea level.
jimh	posted 02-21-2005 01:26 PM ET (US) Good points. Let's consider this: A decrease in air density causes a decrease in horsepower. This happens no matter what caused the decrease in air density. I assume that colder air is more dense than warmer air. Thus an engine operating at an air temperatures of 40-degrees would have more horsepower than the same engine at 100-degree air temperature. How much does the density of air change per degree versus how much does it change per 1,000 feet of altitude. With this information we could compare the affect that temperature has to the effect that altitude has. Maybe we all need propellers for cold days and hot days, too.
Joe Kriz	posted 02-21-2005 01:32 PM ET (US) Highsierra, I went through this a couple of years ago on a "Carbed" Evinrude engine. The jets on a carbed engine are only changed for (High) altitudes of 5,000 feet and higher, meaning they will run lean if you take this same engine to Sea Level without changing the jets back to the original ones used for Sea Level. (Don't confuse changing the jets slightly so this particular engine runs better at a certain altitude below 5,000 feet. Most carbed engines are slightly adjusted for optimum performance by changing the idle jets in a particular situation.) As Sal mentions above, you could ruin the engine by running High Altitude jets at Sea Level. Don't Do It... If your engine is EFI or DFI, then the computer will take care of the fuel/air mixture and the prop is the only thing you might need to change for optimum performance.
onlyawhaler	posted 02-21-2005 01:59 PM ET (US) Altitude is a huge factor in carb outboards. Since I have never owned a EFI or DFI I cannot comment on first hand experience. However, here is the real life effect on an 18 Outrage with a 80s era carb Johnson 150. Most dealers in the area from that time left stock sealevel jets in the outboards. The reason is that if a carb outboard at this altitude (4500-7000ft)at the popular lakes here in Utah is tuned with high altitude jets the owner runs the risk of burning up the powerhead if it is taken and run at sea level and not remembering to change out jets. Lower altitude, more air, same fuel mixture= leaner mixture. I have run my outrage at 6-7000 feet and then at Lake Mead down by Las Vegas which I believe is close to 1000 feet and the difference in performance is very noticable. I change from a 17 to a 19 pitch prop or I will over rev. In talking with a few friends who are in the bass boat market, it is the same with EFI according to them. They run better with less smoking than my carb unit, but they still experience more power when boating at lower lakes vs higher lakes. Hole shots are better, acceleration is better, everything is better at lower altitude. It is interesting to see the difference in Sea Rays, Bayliners and the local market up here vs down there anywhere. A Searay Sundancer works fine a sea level with a 5.7 GM 350 V-8, but wouuld struggle to even get on plane up here. Dealers typically max out the available horsepower options and also change out the gearcase in most instances on the outdrives to the altitude gear cases options to help out the situation. Onlyawhaler
Jerry Townsend	posted 02-21-2005 02:47 PM ET (US) Hey guys - it is not only density - but also the atmospheric pressure - which really changes the air/fuel ratio. Density is only one part of the equation. At sea level, there will be more air drawn into the carburetor than at some higher elevation for the same engine conditions. I have not heard the 3 - 4% per thousand feet that Kemp (kglinz) quotes - but it should be in the ball-park. And of course, should one be moving from or to a significant change in altitude - it is prudent to change the jets on your carburetor. Also, High Sierra's question concerns the affect of altitude on the performance of the prop. There will indeed, be an altitude affect - but I suspect that any affect will be principally realized in really high performance applications where cavitation is more apt to come into play. There should be less cavitation at sea level than at a high elevation for the same rpm/power (prop). Therefore, a prop that works well at altitude should work well at sea level. This is another "wrinkle" that has not been addressed before and my first swing through some technical stuff came up dry - I will put it on a front burner and see what I can come up with in the near future.
high sierra	posted 02-21-2005 04:01 PM ET (US) To all, the prop is just as efficient at sea level as it is at high altitude. The density of the water is the same. It is the lack of dense air, or atmospheric pressure, (the proper term , thanks Jerry )that doesn't let the engine produce the torque and horsepower. We at this height, figure 3% loss per 1000 feet and that is an understatement. As stated by Sal, it seems like a lot more power than that is lost ,and it is. The upper part of the powerband is where the torque is developed and the engine usually fails to get to that rpm due to the lack of atmospheric pressure and being overproped. The salton sea is a good example of the opposite end of the spectrum. ( Binkie is right ) The average prop has to be downsized 3 to 6 inches less pitch just to plane the boat. (thanks 15ftlover for the exact spec.) High Sierra
15ftlover	posted 02-21-2005 05:14 PM ET (US) High sierra, Our dealer originally put a 17 inch aluminum prop on the boat and delivered it as being "ideal". They obviously made a mistake (overpropped at sea level) as we could not get above 5400-5500 RPM with the 17 inch. Let me know how you do if you can find a 3 blade SS 14 inch. I am impressed at the altitude effect, I generally feel our new motor is provides plenty of power down here in Charleston Hen
Jerry Townsend	posted 02-21-2005 07:30 PM ET (US) High Sierra - the efficiency of the prop will be basically the same under normal operation at sea level and at an elevated altitudes. And, for all practical purposes, the density will be basically the same - though, in actuality, there will be insignificant difference - because of the different pressure and temperature. But - a heavily loaded prop will cavitate at higher elevations, and the efficiency go to hell, whereas it would not cavitate at sea level with the same rpm/power conditions - due to the decreased pressure at the plane of the prop at an elevated altitude. And forgetting all of this stuff - you probably can't tell the difference in the prop performance at sea level and being up in the air 5000 feet or so. ------ Jerry/Idaho
high sierra	posted 02-21-2005 07:43 PM ET (US) Jerry , where is this decreased pressure at the plane? of the prop? Are you trying to dazzle me with brilliance or baffle me with ** **? I can be swayed with logic. High Sierra
high sierra	posted 02-21-2005 07:56 PM ET (US) Jerry, that is meant to be a funny line, from a firehouse. No harm intended. Appreciate your input. thanks
brainstormer	posted 02-21-2005 08:22 PM ET (US) just some additional data a '84 70hp Evinrude on my 17' Supersport with a 17 pitch prop got up and did ok @ 2500 ft above sealevel, but when taken to Pactola Res. in So. Dak. @ 6400' wouldn't get up on a plane for almost an 1/8th of a mile and had trouble even starting it. Next year with a 93 90hp Johnson it would get up on plane ok, but wouldn't come close to WOT rpm's, same prop. same boat. This year we'll see what a '99 115 will do come 4th of July.
Jerry Townsend	posted 02-22-2005 02:21 AM ET (US) High Sierra - no problem. The only thing I was trying to say is - the reduced atmospheric pressure at some elevated altitude would tend to induce cavitation easier than the same prop loading conditions at sea level. But again - I doubt that anyone could really tell any difference in the performance of the prop at sea level and then at some elevated altitude. --- Jerry/Idaho
skookum point	posted 02-22-2005 02:26 AM ET (US) hi sierra, I have owned several boats powered with 2-stroke outboards that I have trailered back and forth between Puget Sound (sea level)and Utah/Idaho mountain lakes (7000+ ft). In every case a 3" to 4" change in pitch has adequately compensated for loss of power at altitude. For example, my 15' Whaler with a 50hp OMC would turn a 17" prop at sea level but needed a 13" at 7500 ft to get the same revs. Now I am in the process of preparing a high altitude Montauk (125hp Merc) for use at sea level. I have rejetted the carbs back to the original sizes. At 7000 ft it ran well with a 21 pitch prop. I'm betting it will turn a 24pitch at sea level. Hope that helps. John
high sierra	posted 02-22-2005 11:38 AM ET (US) Thanks to all! High Sierra