Perfect intake centerline

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You mean when the intake opens? Or cam centerline like a 110 and the intake is on a 106 and should it be moved to 104?

It's based on a few factors. Cube size, cam profile and performance goal.

A 110 is a typical centerline of a performance cam. I would prefur a 108 on my 360 and have had it down at 106. The idle gets ruffer the lower it goes. But this also is part of the cams profile.

I like a 112 to 110 for a 318
110-108 for the 340 and 360 for general performance up to a preety stout engine.
Minus 2* for a race engine and up to 4* for a all out engine.

Alot of this topic is realy tasters choice.
 
I am talking about degeeing a cam, to get the best performance result.
The lobe centerline angle is ground into the cam profile, but the intake centerline can be set from the mechanic.
For example - my english isn´t perfect
When I am looking in the instruktion manual of my 2177 Edelbrock camshaft, I can see a 110° lobe centerline angle and a 106° intake centerline.
Timing at .050 Lift:
Open Intake 4° ATDC 28° ABDC
Close Exhaust 36° BBDC 12° BTDC

With the bad duration this cam is having low overlap. But when I change the intake centerline, I might get better times?

I hope you understand my question.

Best regards - Martin
 
I think if it were me, I'd install it straight up (106) and run it. It's not a very good cam anyway, but if you need or want to run it, leave it at 106.
 
Where ya from? Your English is better than most.

The Edel. cam, as Moper said, is very small and I would not expect much of anything from it.

You'll need a degree wheel to find out where it is and where it'll stand after a change in ethier crank key, cam woodruff key change.
 
I am from Germany, Hamburg.:pirat:

So everyone is following the requirements of the manufacturer?????

I can not belive that a cam work on different circumstances, like in a 273 or 360, and having the same intake centerline.
I would have thought that there is a difference in timing.
Its not about the 2177. It was just an example.
 
When you install a cam you can advance and retard the timing of the valves to give a lower or higher rpm band for the engine.
You are also changing the cylinder pressure of the engine.

The cam you are using is one of the smaller performance cams from edelbrock.
Edelbrock should be able to give you the (installed degrees)that the cam should be installed at.
Call edelbrock for additional information.

The cam you bought is a small performance cam.
I would use the degree wheel and double check that the INTAKE is at MAXIMUM LIFT a --106 degrees --PAST TOP DEAD CENTER on the INTAKE STROKE with the degree wheel.
If it all lines up good, and everything is correct with the cam and the key way on the sprocket you will see both the dots line up on the cam and crank sprocket.

A cam of this size, i would think would be installed ---strait up-- due to it being a smaller performance camshaft.
Again call edelbrock to be sure and go from there.

I think your original question is about the cams LOBE SEPARATION ANGLE.
This is the measurement of how close both the intake and exhaust lobes are in comparison to each other.

Example:intake center line of 106 degrees.
exhaust center line of 110 degrees.

By adding them together you will have a total of 216 degrees.
Divide the total of your intake and exhaust center lines by 2 and you will get a LOBE SEPARATION ANGLE of 108.

This is a cam ground on a 108 LOBE SEPARATION ANGLE.

This number can not be changed since it is the shape of the cam and how it was manufactured by the cam company.

It is one of the biggest factors of how a engine will perform and it also gives the over lap it's distance.
The over lap is the amount of time both the exhaust valve and intake valve are open at the same time.

A wide lobe separation angle will give a flatter torque band but will make less peak power.
A tighter lobe separation angle will make more torque and horse power but at a narrower power band.

This is why drag race cams sometimes have a tighter LSA and so due good tow cams.
They both give a narrow peak power band.
When working in a narrow peak power band of a drag car or tow vehicle and also some stock engines looking for torque down low, this is exactly what is needed.

It all depends on what usable rpm you want for your engine and the limitations of the cylinder heads air flow compared to the cubic inch and where the torque and horse power will start and stop with each cam you select.

A lot of people miss the boat by picking a cam with a wide lobe separation angle.

It's when you start going to better flowing cylinder heads and larger cubic inches that the lobe separation angle goes higher.

I hope this helps.:cya:
 
By the way, what cubic inch engine do you have and what cylinder heads are you using.
Are the valves stock???
 
Wedgy Perfect intake centerline
Hi together,

how can I calculate the perfect ICL for my engine?

Best regards - Martin



Remember that the intake valve closing point will change the dynamic compression of the engine.
A engine cannot make any compression until the intake valve closes shut.

This is what your adjusting when installing your cam.
The intake valve closing point.

The perfect ICL is choosing a cam that shuts the intake valve at the right time to give you the cylinder pressure you would like and also the rpm band you would want to see your engine operate at most efficiently.

This is why most small performance cams have a faster closing intake valve.
A faster closing intake valve helps a lower compression engine make more power due to trapping more air at a lower rpm.

A higher rpm engine will close the intake valve at a latter time and can get away with this because the engine is used at a higher rpm.
The cylinders are being filled more efficiently due to the rpm.

This is a complicated subject and it can go on and on and on..................

PS
I understand the basics of camshaft blueprinting but this is where my knowledge ends on the subject.

Every engine needs a cam but what cam will it be?????
This could be the biggest bench racing subject ever.

GOOD LUCK.:salute:
 
I just seen that you only used the small edelbrock cam as a example.
I heard you say you where looking in YOUR INSTRUCTION MANUAL for your cam and assumed you owned it.
I wrote a response and then noticed you posted something while i was writing one of my responses.
Anyways..............
I hope what i wrote has helped you.

Did you buy a cam yet or do you have one already?????
 
Thanks a lot for your comments :thumrigh:

I really talked about the ICL and not the lobe centerline angle.
I am concerned with the perfekt timing of a cam.

Here the components of my engine.

Intake
Edelbrock Performer 318/360 small port

Heads
318 heads from 1970. I checked the cc.
To get the right CR of 9.5:1 to 10:1 I have to mill the heads about 0.06".
Porting
1.78" intake valve
1.6" ekhaust valve

Camshaft
Isky E-4
Valve Lift 0.425 / 0.425
.050 Duration 216 / 216
LC 108

The engine is for my 65 Valiant. I will drive the car with a 904 and for the first time with a 7 1/4 rear end (2.76).
But I will change the rear end to a 8 3/4 (3.55).
I will build a hot street car. A time on the strip of ~14.5 to 14 sec. would be perfekt.

http://www.forabodiesonly.com/mopar/showthread.php?t=132159

Regards Martin
 
Are you using a 1.6 rocker?????
Ether way that's a good cam.
 
This is interesting because you have chose a perfect cam for your engine and it will work good with any gear ratio.

:idea1:
You asked for it.............

If this is a standard or a higher stall automatic, you might want to retard the cam two to three degrees for a higher rpm range.....

You are at a premium position to make a small adjustment.

I think 9.5 to 1 is max for your compression unless your going to run premium fuel.
If you go to 10.0 to 1 then i would retard the cam 2 to 3 degrees.

In fact i don't know if you could get away without using ANYTHING LESS THEN 89 octain at 9.5 to 1 with the cam installed strait up.

This might even be a premium gas engine the way it is.

So it's really about the fuel you want to use.

My 67 cuda has a .453 lift crane cam in a a little over 9.1 to 1 compression in the engine.
The cam is 225 @ 50 and is ground on a 108 LSA.
MY INTAKE CLOSES AT 38 ABDC.
All my timing is in by 2200 to 2300 and i run a 3000 stall convertor with 3.91 gears.
Timing is set at 31 total...................
I cannot run 87 octane fuel because it will detonate under full throttle.
I have to run 89 octane fuel.

Take it for what it is, but it's real world results of the limitations of fuel.
This is something to think about if your going for a max effort engine.

I don't know how you drive but if it's gonna be a racer and the pedal will hit the floor you have to think about it.
 
What do they recommend to install it at? Do you have the cam card info handy you could post?
 
@ moper - No I havn´t. The cam was allready installed.


@ T67POWER - I will run 95 octane fuel (Super/Bleifrei 95)

My 904 is equipped with a /6 converter. I don´t know the stall, but think it is a bit higher then the stock SB converter.
I will get enough power to kick some 318 butts :toothy5:

You are driving a nice set up. What is your best time on the strip?
 
I went 14.38 at 94 mph with no slicks.
I will be installing a 8 3/4 rear with 4.56 gears this summer and adding slicks.
It will be in the 13 teens.
Other then the cam,intake,carb and headers it's a stock 1967 engine rebuilt.
Your cars gonna run great.
Glad to see the correct LSA for your engine.
 
Wedgy - ToolmanMike posted the card. I'd go straight up. It builds a lot of cylinder pressure with that 58°ABDC closing event. No need to try for more and sacrifice any top end it might have.
 
But the cam was installed straight up. The intake centerline was 104,5°.
In the timing chart is no information about the intake centerline, only the lobe center is mentioned.
Information in the card is - cam advance 0°
So, do I have to time the cam on 108° intake centerline?
 
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