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Discussion Starter #1 (Edited)
I could use some icl advice for a 540 street strip engine i'm buliding it is 10.8 compression, afr 315 heads, the cam is a Lunati Voodoo sold roller with 255* 263* at .050 with .680 lift and on a 110 lobe seperation angle, the cam card calls for the icl to be set at 104 but that would be 6* advance which just seems like a lot to me but I live at 5500 feet so maybe a little extra advance is better, I've call Lunati and one guy said to go 106 or 108 and another guy said to stay with the 104 so any help from you cam gurus would be great
Thnks John
 

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I could use some icl advice for a 540 street strip engine i'm buliding it is 10.8 compression, afr 315 heads, the cam is a Lunati Voodoo sold roller with 255* 263* at .050 with .680 lift and on a 110 lobe center, the cam card calls for the icl to be set at 104 but that would be 6* advance which just seems like a lot to me but I live at 5500 feet so maybe a little extra advance is better, I've call Lunati and one guy said to go 106 or 108 and another guy said to stay with the 104 so any help from you cam gurus would be great
Thnks John
I think your confusing the lobe seperation angle of 110* with the recommended 104* intake centerline.
Lobe sep. angle is degrees from intake lobe centerline to exhaust lobe centerline. The 104* intake centerline is a reference from TDC of the piston to the exact centerline of the intake lobe.
Advancing the cam will ususally give a little more bottom end and maybe kill a tiny bit of top end, retarding does the opposite. Check piston to valve clearances. Advancing/retarding changes clearances.
I would stay with the 104 myself.
 

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Discussion Starter #3 (Edited)
Sorry I ment 110 LSA, I would like to get a little more top end because I think it is going to have alot bottom end any way and the car is a 69 camaro so it is not that heavy, I am hoping to get peak power in the 6300-6500 range, I'm just not sure how much differance 2* will make.
 

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  1. 255 [email protected] .050
  2. 10.8:1 compression (I bet it's less)
  3. operating range 6,300 rpm
  4. rear end ratio hardly matters, cam is too big even if you are running 455s
WRONG CAM, put it in anywhere you want and it won't perform as well as the correct cam simply installed close to where it should be.
It's all about the combination, heads, comp ratio and operating range are good until you get to the cam.

Just my opinion
 

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steelcomp was here
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Run it like it is. Nothing wrong with that cam and your combination.
Just out of curiosity, where does the intake open and close?
 

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Resident Ford Nut
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Run it like it is. Nothing wrong with that cam and your combination.
Just out of curiosity, where does the intake open and close?

I'll second that.


S CP
 

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Discussion Starter #7
Run it like it is. Nothing wrong with that cam and your combination.
Just out of curiosity, where does the intake open and close?
intake opens at 23.5* closes 51.5* at .050 so are you saying run it at the recommended 104 ICL

Luke here is how I came up with 10.8
custom JE piston 19cc dome
Bore 4.5
Stroke 4.25
Head gasket .039 X 4.540
Piston down in the hole .005
Head volume 120cc
what do you come up with
 

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steelcomp was here
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intake opens at 23.5* closes 51.5* at .050 so are you saying run it at the recommended 104 ICL

Luke here is how I came up with 10.8
custom JE piston 19cc dome
Bore 4.5
Stroke 4.25
Head gasket .039 X 4.540
Piston down in the hole .005
Head volume 120cc
what do you come up with
Yep. I'd leave it right where it is. Compression is correct. If you take into consideration the area around the piston above the top ring it might be 10.78...close enough.
 

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northern member
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I'll second that.


S CP
x3 on the cam being ok . would think in your camaro if your intake and exhaust are working i'd go with 108 ic/l :thumb:
 

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sport,

I don't doubt that your math is correct, I think my point is that 90% of people that bring their motor in to me when I check it the compression it's almost always lower then they think it is. That being said I always fill the cylinder up when motor is fully assembled and CC it that way, I just think that is more acurate. Anyway a half point either way is not the real issue I see. I think that [email protected] .050 means the cam wants to run in the 7500 rpm range. I think if you are going to error I would rather error towards the small and of the scale. A cam with [email protected] .050 would probably be a much better selection and on a 106-108 would be much funner to drive and act like a raped ape to 6500.
Just my thinkin, good luck

luke
 

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sport,

I don't doubt that your math is correct, I think my point is that 90% of people that bring their motor in to me when I check it the compression it's almost always lower then they think it is. That being said I always fill the cylinder up when motor is fully assembled and CC it that way, I just think that is more acurate. Anyway a half point either way is not the real issue I see. I think that [email protected] .050 means the cam wants to run in the 7500 rpm range. I think if you are going to error I would rather error towards the small and of the scale. A cam with [email protected] .050 would probably be a much better selection and on a 106-108 would be much funner to drive and act like a raped ape to 6500.
Just my thinkin, good luck

luke

Keep in mind that this thing is 540 CI... 245 @ .050 might get you to the grocery store or church on sunday :deadhorsejz2:.... 255 @ .050 WILL pull to 7500RPM.... in a small block... JMO...
 

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steelcomp was here
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sport,

I don't doubt that your math is correct, I think my point is that 90% of people that bring their motor in to me when I check it the compression it's almost always lower then they think it is. That being said I always fill the cylinder up when motor is fully assembled and CC it that way, I just think that is more acurate. Anyway a half point either way is not the real issue I see. I think that [email protected] .050 means the cam wants to run in the 7500 rpm range. I think if you are going to error I would rather error towards the small and of the scale. A cam with [email protected] .050 would probably be a much better selection and on a 106-108 would be much funner to drive and act like a raped ape to 6500. Just my thinkin, good luck

luke
Curious how you know this simply by the .05 numbers.
 

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Sorry I ment 110 LSA, I would like to get a little more top end because I think it is going to have alot bottom end any way and the car is a 69 camaro so it is not that heavy, I am hoping to get peak power in the 6300-6500 range, I'm just not sure how much differance 2* will make.
You still arent getting it. The LSA is ground into the cam and cant be changed. The ICL is where the cam is in reference to the crank and can be changed. Stick with the 104 that the card asks for.
 

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When doing the NASCAR engines they had to be no greater than a certain compression, to prevent embarrassment and loosing a race due to over compression we whistled every engine! This is done with rocker arms off and engine temperature as close to operating range as possible.

Good luck!
 

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Discussion Starter #15
You still arent getting it. The LSA is ground into the cam and cant be changed. The ICL is where the cam is in reference to the crank and can be changed. Stick with the 104 that the card asks for.
I know what LSA means and that is not what I was thinking about changing, the Intake Center Line is what I was going to change but I think I will do what steelcomp and others have said and put it in at 104 like the cam card said. Thanks for the help.
 

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My understanding, as to what you are asking is that the ICL is 110 installed straight up, and someone is recommending that you install at 104 degrees ICL, with an adjustable timing chain, to give you six degrees of advance? I think your duration numbers are fine with the 540. My 548 made good power with a 258 270 680 680 LSA of 112, and it peaked at 6400. It was installed straight up at 112 and the intake opened at 20*.
 

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Keep in mind that this thing is 540 CI... 245 @ .050 might get you to the grocery store or church on sunday :deadhorsejz2:.... 255 @ .050 WILL pull to 7500RPM.... in a small block... JMO...
Agreed. 255 with 540 CID is not big. At high elevation I would open that intake valve as soon as possible. I would leave it at 104 and run it. If you want to do some tuning down the road and pick up some power, I would advance it to 102, she'll pick up. Then I would loosen the exhaust lash and narrow up the split. This will put some more power in it.
 

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Right, if his cam is too big, my 270,276 at .050 and .750, .714 in my 548 ci 10.2 comp street engine must be way off. Doesn't seem that way though, it will fry the 325/50 drag radials in second gear on the street.:wink2:
 

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I know what LSA means and that is not what I was thinking about changing, the Intake Center Line is what I was going to change but I think I will do what steelcomp and others have said and put it in at 104 like the cam card said. Thanks for the help.
If the card asks for 104 ICL that means to achieve the specs you see on the card you need to install it at 104 ICL , thats were the cam was ground. So why do you think putting it in at 104* means you are advancing it 6 degrees? If its ground for a 104 ICL , that should be achieved putting the cam in straight up but still should be checked. I think the two #'s were confusing you.
 

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Discussion Starter #20
Agreed. 255 with 540 CID is not big. At high elevation I would open that intake valve as soon as possible. I would leave it at 104 and run it. If you want to do some tuning down the road and pick up some power, I would advance it to 102, she'll pick up. Then I would loosen the exhaust lash and narrow up the split. This will put some more power in it.
Thanks for that info. Chris. I was hoping you would jump in with your opinion. I will be going to Westech hopefully in May to see what it will do.
Thanks again John
 
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