Reversion what is the impact?
04-15-2006, 10:00 PM
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Re: Reversion what is the impact?
Rage:
Your 496HO engine is an efi motor and if you got a fairly correct cam in there the LSA of the cam is the most important number. On a 496 efi that number should be between 115 to 119 degrees. If its not you could develop a serious reversion problem. If your motor idles smoothly down at 650 rpms in gear I suspect you have a correct LSA and reversion should not be a problem for you.
Ray @ Raylar
Your 496HO engine is an efi motor and if you got a fairly correct cam in there the LSA of the cam is the most important number. On a 496 efi that number should be between 115 to 119 degrees. If its not you could develop a serious reversion problem. If your motor idles smoothly down at 650 rpms in gear I suspect you have a correct LSA and reversion should not be a problem for you.
Ray @ Raylar
05-10-2006, 09:22 AM
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Re: Reversion what is the impact?
Originally Posted by Raylar
Rage:
Your 496HO engine is an efi motor and if you got a fairly correct cam in there the LSA of the cam is the most important number. On a 496 efi that number should be between 115 to 119 degrees. If its not you could develop a serious reversion problem. If your motor idles smoothly down at 650 rpms in gear I suspect you have a correct LSA and reversion should not be a problem for you.
Ray @ Raylar
Your 496HO engine is an efi motor and if you got a fairly correct cam in there the LSA of the cam is the most important number. On a 496 efi that number should be between 115 to 119 degrees. If its not you could develop a serious reversion problem. If your motor idles smoothly down at 650 rpms in gear I suspect you have a correct LSA and reversion should not be a problem for you.
Ray @ Raylar
What would be the reversion potential of LSA114 degrees in your opinion?
Bill
05-10-2006, 10:15 AM
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Re: Reversion what is the impact?
Rage
They are talking about quick & quiet or silent choice exhaust, where your exhaust can be switched between a full thru the prop exhaust and out the transom tailpipes. These systems can back exhaust exit water back up in the sytem and lead to some serious reversion. with the cam spec you've listed on your 496 with a probable 116 to 119 lsa on that fuel injected cam, reversion won't be a big issue, but valve and seat corrosion can be. The stock GM iron heads come with iron head material machined in head seats and cheap steel valves that can rust when subjected to cool down moisture in the system especially on the valves that are left hanging open, This is why we use high quality stainless steel valves that are QPQ nitrited in our aluminum heads. No corrosion period!
Ray @ Raylar
They are talking about quick & quiet or silent choice exhaust, where your exhaust can be switched between a full thru the prop exhaust and out the transom tailpipes. These systems can back exhaust exit water back up in the sytem and lead to some serious reversion. with the cam spec you've listed on your 496 with a probable 116 to 119 lsa on that fuel injected cam, reversion won't be a big issue, but valve and seat corrosion can be. The stock GM iron heads come with iron head material machined in head seats and cheap steel valves that can rust when subjected to cool down moisture in the system especially on the valves that are left hanging open, This is why we use high quality stainless steel valves that are QPQ nitrited in our aluminum heads. No corrosion period!
Ray @ Raylar
05-10-2006, 01:49 PM
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Re: Reversion what is the impact?
Originally Posted by Raylar
Rage
They are talking about quick & quiet or silent choice exhaust, where your exhaust can be switched between a full thru the prop exhaust and out the transom tailpipes. These systems can back exhaust exit water back up in the sytem and lead to some serious reversion. with the cam spec you've listed on your 496 with a probable 116 to 119 lsa on that fuel injected cam, reversion won't be a big issue, but valve and seat corrosion can be. The stock GM iron heads come with iron head material machined in head seats and cheap steel valves that can rust when subjected to cool down moisture in the system especially on the valves that are left hanging open, This is why we use high quality stainless steel valves that are QPQ nitrited in our aluminum heads. No corrosion period!
Ray @ Raylar
They are talking about quick & quiet or silent choice exhaust, where your exhaust can be switched between a full thru the prop exhaust and out the transom tailpipes. These systems can back exhaust exit water back up in the sytem and lead to some serious reversion. with the cam spec you've listed on your 496 with a probable 116 to 119 lsa on that fuel injected cam, reversion won't be a big issue, but valve and seat corrosion can be. The stock GM iron heads come with iron head material machined in head seats and cheap steel valves that can rust when subjected to cool down moisture in the system especially on the valves that are left hanging open, This is why we use high quality stainless steel valves that are QPQ nitrited in our aluminum heads. No corrosion period!
Ray @ Raylar
Just to make sure I understand you, the LSA on my cam is 114. I thought that a given physical cam can have only one LSA. I am unclear about your meaning when you said "with the cam spec you've listed on your 496 with a probable 116 to 119 lsa".
Does reversion increase when the LSA is a (1.) larger numerical value i.e. greater than LSA119 or (2.) a smaller numerical value i.e. less than LSA115 or (3.) both when the LSA is a larger numerical value i.e. greater than LSA119 or a smaller numerical value i.e. less than LSA115.
Thanks,
Bill
05-10-2006, 09:31 PM
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Re: Reversion what is the impact?
Originally Posted by Rage
Thanks as always for the information Ray.
Just to make sure I understand you, the LSA on my cam is 114. I thought that a given physical cam can have only one LSA. I am unclear about your meaning when you said "with the cam spec you've listed on your 496 with a probable 116 to 119 lsa".
Does reversion increase when the LSA is a (1.) larger numerical value i.e. greater than LSA119 or (2.) a smaller numerical value i.e. less than LSA115 or (3.) both when the LSA is a larger numerical value i.e. greater than LSA119 or a smaller numerical value i.e. less than LSA115.
Thanks,
Bill
Just to make sure I understand you, the LSA on my cam is 114. I thought that a given physical cam can have only one LSA. I am unclear about your meaning when you said "with the cam spec you've listed on your 496 with a probable 116 to 119 lsa".
Does reversion increase when the LSA is a (1.) larger numerical value i.e. greater than LSA119 or (2.) a smaller numerical value i.e. less than LSA115 or (3.) both when the LSA is a larger numerical value i.e. greater than LSA119 or a smaller numerical value i.e. less than LSA115.
Thanks,
Bill
