[BeauRichardson]

I need some help reading the cam specs. Actually, i need to learn how to read them in general. So please, explain.



Here are the specs i need help with

23x/24x .64x"/.63x 114+5


When i looked up how to read them, it was a 3 digit number. Not 2 digits with an "x" In this case, does the x just mean 0? Making it a 3 digit number?
If so, would these specs be "230/240 .640/.630 114+5"


And, what are these numbers?


Thanks in advance. I don't want to sound stupid but cam specs have always confused the crap out of me.

[SJFGTO]

There are 3 numbers. Whatever you are looking at is not giving you the third number. Some cam companies keep their complete specs confidential, but give you just enough info to determine if it is the right one for you. Cams typically come with a cam card which has all the specs. The first series is the intake and exhaust duration, the second series is the lift on the intake and exhaust sides. The final number is the lobe separation angle. Hope this helps.

[JSH]

Originally Posted by BeauRichardson

I need some help reading the cam specs. Actually, i need to learn how to read them in general. So please, explain.



Here are the specs i need help with

23x/24x .64x"/.63x 114+5


When i looked up how to read them, it was a 3 digit number. Not 2 digits with an "x" In this case, does the x just mean 0? Making it a 3 digit number?
If so, would these specs be "230/240 .640/.630 114+5"


And, what are these numbers?


Thanks in advance. I don't want to sound stupid but cam specs have always confused the crap out of me.

If you're considering a new cam, I would call a vendor or a shop you would consider for doing the work. There are a bunch of cams available to you that have been designed for specific builds.

[Spaceme1117]

The x's are there because the cam company wants to keep the exact specs secret.

As for what the numbers mean, I will use the specs for the stock LT1 as the example:

200/207 0.551/0.524 116.5

200/207 is the number of degrees of crank rotation that the intake / exhaust valves are opened when the lobe of the cam just starts to open the valves. This is usually listed as duration @ 0.050 inches of lift. It is a good way to be able to compare different cams to each other. The higher the numbers, the longer the valves are open which typically will allow more flow through the engine or more power. Larger displacement engines typically need more duration as they need more time to be able to fill the cylinders. And in general more duration usually results in a rougher idle. Higher duration also typically shifts the power band higher in the RPM range. (This is very, very general.)

0.551/0.524 is the maximum lift in inches that the lobe opens the intake/exhaust valves after multiplying by the rocker arm ratio which is 1.8 on the LT1. Typically, higher lift will result in more power. It also puts more stress on springs and the valve train. And valves springs need to be matched to the cam to be able to handle the lift.

116.5 is the LSA or Lobe Separation Angle. It is the number of degrees between the centerlines of the intake and exhaust lobes of the cam and is an indication of how much overlap there is between intake and exhaust valves. Less overlap gives a smoother idle while more overlap results in rougher or "lopey" idle.

If you see an extra number next to the LSA, "114+5" it means that all of the lobes will be shifted or advanced by 5 degrees which can give more performance. It really depends on the application the cam will be used in.

There is a lot more to cams and all of these parameters influence and are tied to each other.

Just do a lot of reading. Tons of information out there.

And if you are thinking of getting an aftermarket cam for your car, you need to decide what your car will be used for as this will dictate the type of cam you need.

[BeauRichardson]

Originally Posted by SJFGTO

There are 3 numbers. Whatever you are looking at is not giving you the third number. Some cam companies keep their complete specs confidential, but give you just enough info to determine if it is the right one for you. Cams typically come with a cam card which has all the specs. The first series is the intake and exhaust duration, the second series is the lift on the intake and exhaust sides. The final number is the lobe separation angle. Hope this helps.

Thank you! It definitely helped with my confusion

[BeauRichardson]

Originally Posted by JSH

If you're considering a new cam, I would call a vendor or a shop you would consider for doing the work. There are a bunch of cams available to you that have been designed for specific builds.

I wouldn't say im considering getting a different cam, but btr is about to launch a new cam and i just wanted to compare and contrast the cam specs to see if it would be a good fit for what i have done as far as a bigger cam vs what i have now

[BeauRichardson]

Originally Posted by Spaceme1117

The x's are there because the cam company wants to keep the exact specs secret.

As for what the numbers mean, I will use the specs for the stock LT1 as the example:

200/207 0.551/0.524 116.5

200/207 is the number of degrees of crank rotation that the intake / exhaust valves are opened when the lobe of the cam just starts to open the valves. This is usually listed as duration @ 0.050 inches of lift. It is a good way to be able to compare different cams to each other. The higher the numbers, the longer the valves are open which typically will allow more flow through the engine or more power. Larger displacement engines typically need more duration as they need more time to be able to fill the cylinders. And in general more duration usually results in a rougher idle. Higher duration also typically shifts the power band higher in the RPM range. (This is very, very general.)

0.551/0.524 is the maximum lift in inches that the lobe opens the intake/exhaust valves after multiplying by the rocker arm ratio which is 1.8 on the LT1. Typically, higher lift will result in more power. It also puts more stress on springs and the valve train. And valves springs need to be matched to the cam to be able to handle the lift.

116.5 is the LSA or Lobe Separation Angle. It is the number of degrees between the centerlines of the intake and exhaust lobes of the cam and is an indication of how much overlap there is between intake and exhaust valves. Less overlap gives a smoother idle while more overlap results in rougher or "lopey" idle.

If you see an extra number next to the LSA, "114+5" it means that all of the lobes will be shifted or advanced by 5 degrees which can give more performance. It really depends on the application the cam will be used in.

There is a lot more to cams and all of these parameters influence and are tied to each other.

Just do a lot of reading. Tons of information out there.

And if you are thinking of getting an aftermarket cam for your car, you need to decide what your car will be used for as this will dictate the type of cam you need.

Thank you! That's a lot of useful information and i will definitely be reading deeper into all of this. Not sure if I'm actually going to swap to a different cam because the cam i have right now is pretty big, but i wouldn't mind having something bigger if it would benefit more so than what i have and if i could justify the cost, etc.