flycut how big of lift can i go
#1
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flycut how big of lift can i go
well its a lq9 n i got 799heads 64cc but plan on gettn a set of 2.5 cnc heads off this site wanta stick with 64cc just want to no whats the biggest cam i can go with? rite now im plannin on puttin in a torqrv 2 dat i got but really want to install a bigger cam if it will give me more hp.
#2
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Actually, the maximum lift of the camshaft is not a piston-to-valve issue. The piston only come close to the valves when it is at, or nearly at, top dead center (TDC). The occurs only twice during an engine cycle.
It occurs once as the piston comes up on the compression stroke. On this stroke however, both valves are closed.
The second time the piston approaches TDC is on the exhaust stroke. During the exhaust stroke the exhaust valve is open but is already retreating from its maximum lift as the piston rises. The piston can hit the exhaust valve if, and only if, the exhaust valve retreats too slowly. Under no circumstances however, can the piston catch the exhaust valve at its maximum lift.
On this same exhaust stroke, the intake valve is beginning to open (which constitutes overlap with the retreating exhaust valve). The intake valve, can hit the piston if it opens to soon and the piston is at, or nearly at, TDC. However, the intake valve will not hit is maximum lift until the piston is past TDC and is on the way down (the intake stroke).
It occurs once as the piston comes up on the compression stroke. On this stroke however, both valves are closed.
The second time the piston approaches TDC is on the exhaust stroke. During the exhaust stroke the exhaust valve is open but is already retreating from its maximum lift as the piston rises. The piston can hit the exhaust valve if, and only if, the exhaust valve retreats too slowly. Under no circumstances however, can the piston catch the exhaust valve at its maximum lift.
On this same exhaust stroke, the intake valve is beginning to open (which constitutes overlap with the retreating exhaust valve). The intake valve, can hit the piston if it opens to soon and the piston is at, or nearly at, TDC. However, the intake valve will not hit is maximum lift until the piston is past TDC and is on the way down (the intake stroke).
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what he's trying to say is overlap and duration are more of a factor than lift. If the valve is open too long the piston will contact the valve. Your tv2 will clear fine. If you go with a 24x or more duration and big split with large lift you can run into problems. Only real way is to check ptv with cam installed
#7
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what he's trying to say is overlap and duration are more of a factor than lift. If the valve is open too long the piston will contact the valve. Your tv2 will clear fine. If you go with a 24x or more duration and big split with large lift you can run into problems. Only real way is to check ptv with cam installed
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#8
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If you search hard youll find people with MS3s and 4s that dont flycut and youll find some with the same cam/setup and they had to fly cut. I would think an MS3 at least would clear of course some have gone BIGGER without cutting. I would think if you got an MS3 or similar and had clearance problems you could go up a little on the gaskets.
Any reason you want to go BIG with the cam? Are you searching for HP numbers or trying to go fast? I have found that big HP doesnt necessarily make you fast at all. (I LOVE BIG CAMS tho) If you are picking my method is to go search around here find a FEW people with a similar setup to what you are looking for and when they are performing to what would satisfy you. Copy them and find ways to improve the setup your own way. This entire forum to me is a big RESEARCH tool. Info and experiences about just about everything are in here.
Any reason you want to go BIG with the cam? Are you searching for HP numbers or trying to go fast? I have found that big HP doesnt necessarily make you fast at all. (I LOVE BIG CAMS tho) If you are picking my method is to go search around here find a FEW people with a similar setup to what you are looking for and when they are performing to what would satisfy you. Copy them and find ways to improve the setup your own way. This entire forum to me is a big RESEARCH tool. Info and experiences about just about everything are in here.
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thanx for the advice and replies guys ive been researching but didnt really find much ill keep looking want hp and decent time at track really want ms3 or custom cam with similiar specs.ima check my gasket thickness if you no any one with a lq9 setup please let me no what they have .this is my first f body or ls engine so be gentle guys