ICL vs. .050” Cam Degreeing Methods

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elwood
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Re: ICL vs. .050” Cam Degreeing Methods

Post by elwood » Mon Jul 09, 2018 6:09 pm

that's why i used the term " mathematical center "

it takes into account asymmetric lobe ramps,

ICL can be used interchangeably if you're not concerned with where the actual center of max lift occurs

LSA now ?

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Re: ICL vs. .050” Cam Degreeing Methods

Post by Warp Speed » Mon Jul 09, 2018 6:42 pm

None of our lobes are symmetrical, and that is the reason we have used the lift center (.050 before and after max) as our centerline reference for ever. It's not like it really matters though, as it's really just a reference number. Every cam gets position swept for best power. When the sweet spot is found, we use a different method for a more accurate install measure of a certain grind in production.
If the cam grinder states doing the centerline using the .050 lift method, so be it. Install it using the .050 opening event, then check the closing to verify the cam was ground to spec. Only takes a minute!
The BIGGEST DEAL is properly locating tdc!

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Re: ICL vs. .050” Cam Degreeing Methods

Post by hoffman900 » Mon Jul 09, 2018 6:52 pm

Warp Speed wrote:
Mon Jul 09, 2018 6:42 pm
None of our lobes are symmetrical, and that is the reason we have used the lift center (.050 before and after max) as our centerline reference for ever. It's not like it really matters though, as it's really just a reference number. Every cam gets position swept for best power. When the sweet spot is found, we use a different method for a more accurate install measure of a certain grind in production.
If the cam grinder states doing the centerline using the .050 lift method, so be it. Install it using the .050 opening event, then check the closing to verify the cam was ground to spec. Only takes a minute!
The BIGGEST DEAL is properly locating tdc!

Ding ding. It’s just a reference point. Everyone repeat that.

Going back to what Walter said. Use whatever the cam grinder told you to use. You can always take your own reference point from there. As long as it’s repeatable who cares where you take it from once you have a baseline.
-Bob

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Re: ICL vs. .050” Cam Degreeing Methods

Post by cjperformance » Mon Jul 09, 2018 7:38 pm

Warp Speed wrote:
Mon Jul 09, 2018 6:42 pm
None of our lobes are symmetrical, and that is the reason we have used the lift center (.050 before and after max) as our centerline reference for ever. It's not like it really matters though, as it's really just a reference number. Every cam gets position swept for best power. When the sweet spot is found, we use a different method for a more accurate install measure of a certain grind in production.
If the cam grinder states doing the centerline using the .050 lift method, so be it. Install it using the .050 opening event, then check the closing to verify the cam was ground to spec. Only takes a minute!
The BIGGEST DEAL is properly locating tdc!
The 2 best quotes so far ^^
**Edited due to dumb typo!
Craig.

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Re: ICL vs. .050” Cam Degreeing Methods

Post by KnightEngines » Mon Jul 09, 2018 8:07 pm

How does everyone else locate exact TDC?

My method is to use a piston stop - plate that bolts to the deck with a large dia bolt in the middle, set to stop the piston roughly 30 deg from TDC, wind the motor over both ways & split the difference, set the degree wheel pointer & verify.

For degreeing I always use .050" on opening & closing ramps - calculating lobe centre, not max lift.

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Re: ICL vs. .050” Cam Degreeing Methods

Post by cjperformance » Mon Jul 09, 2018 8:30 pm

Same here for TDC Tony.
And .050" for degree and lobe center.
If provided i also just do a double check off of intake lift at TDC on O/Lap.
If 2 methods of reference check out OK im happy.
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Re: ICL vs. .050” Cam Degreeing Methods

Post by KnightEngines » Mon Jul 09, 2018 8:51 pm

Yep, same.

How often do you actually get figures that are bang on the cam card? - pretty rare for me, Crane is usually pretty good, camtech a bit hit & miss but close enough, crow are all over the shop on shelf stuff, but similar to camtech on customs.

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Re: ICL vs. .050” Cam Degreeing Methods

Post by hoffman900 » Mon Jul 09, 2018 8:56 pm

KnightEngines wrote:
Mon Jul 09, 2018 8:51 pm
Yep, same.

How often do you actually get figures that are bang on the cam card? - pretty rare for me, Crane is usually pretty good, camtech a bit hit & miss but close enough, crow are all over the shop on shelf stuff, but similar to camtech on customs.
Side bar, but a friend of mine told me in the 1960s that he use to buy several of the same camshaft and measure all the lobes. He'd keep the one that was closes on all the lobes for himself and sell the other.

He's a Crane fan btw, even to this day.
-Bob

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Re: ICL vs. .050” Cam Degreeing Methods

Post by statsystems » Mon Jul 09, 2018 9:06 pm

KnightEngines wrote:
Mon Jul 09, 2018 8:07 pm
How does everyone else locate exact TDC?

My method is to use a piston stop - plate that bolts to the deck with a large dia bolt in the middle, set to stop the piston roughly 30 deg from TDC, wind the motor over both ways & split the difference, set the degree wheel pointer & verify.

For degreeing I always use .050" on opening & closing ramps - calculating lobe centre, not max lift.


I have never used a stop. I use the dial indicator and degree wheel. I can find exact TDC while most guys are sinking with the stop.

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Re: ICL vs. .050” Cam Degreeing Methods

Post by cjperformance » Mon Jul 09, 2018 9:23 pm

KnightEngines wrote:
Mon Jul 09, 2018 8:51 pm
Yep, same.

How often do you actually get figures that are bang on the cam card? - pretty rare for me, Crane is usually pretty good, camtech a bit hit & miss but close enough, crow are all over the shop on shelf stuff, but similar to camtech on customs.
Yeah Id say pretty much the same. I dont use a ton of Crane but definetly the last few have been spot on.
Howards are good.
Camtech and Crow , yeah always find a discrepancy somewhere. That said the last camtech SR i did was spot on(custom grind).
I use the odd budget dynotec, never had a problem as far as lifespan is concerned but have to move every one of then 2 to 4 deg to +/- to be happy. Definitely not one to just chuck in straight up!
Craig.

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Re: ICL vs. .050” Cam Degreeing Methods

Post by cjperformance » Mon Jul 09, 2018 9:30 pm

statsystems wrote:
Mon Jul 09, 2018 9:06 pm
KnightEngines wrote:
Mon Jul 09, 2018 8:07 pm
How does everyone else locate exact TDC?

My method is to use a piston stop - plate that bolts to the deck with a large dia bolt in the middle, set to stop the piston roughly 30 deg from TDC, wind the motor over both ways & split the difference, set the degree wheel pointer & verify.

For degreeing I always use .050" on opening & closing ramps - calculating lobe centre, not max lift.


I have never used a stop. I use the dial indicator and degree wheel. I can find exact TDC while most guys are sinking with the stop.
I know people can stuff anything up !! But yes with a dial indicator it can be done quickly and accuratly and when done properly is no problem.
When a newb does it this way with a loose piston/bore, dial probe not on correct angle etc and no understanding it can get hairy!
Its all in the learning!
Craig.

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Re: ICL vs. .050” Cam Degreeing Methods

Post by Warp Speed » Mon Jul 09, 2018 9:58 pm

statsystems wrote:
Mon Jul 09, 2018 9:06 pm
KnightEngines wrote:
Mon Jul 09, 2018 8:07 pm
How does everyone else locate exact TDC?

My method is to use a piston stop - plate that bolts to the deck with a large dia bolt in the middle, set to stop the piston roughly 30 deg from TDC, wind the motor over both ways & split the difference, set the degree wheel pointer & verify.

For degreeing I always use .050" on opening & closing ramps - calculating lobe centre, not max lift.


I have never used a stop. I use the dial indicator and degree wheel. I can find exact TDC while most guys are sinking with the stop.
Why not use a stop?

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Re: ICL vs. .050” Cam Degreeing Methods

Post by af2 » Mon Jul 09, 2018 10:17 pm

Warp Speed wrote:
Mon Jul 09, 2018 9:58 pm
statsystems wrote:
Mon Jul 09, 2018 9:06 pm
KnightEngines wrote:
Mon Jul 09, 2018 8:07 pm
How does everyone else locate exact TDC?

My method is to use a piston stop - plate that bolts to the deck with a large dia bolt in the middle, set to stop the piston roughly 30 deg from TDC, wind the motor over both ways & split the difference, set the degree wheel pointer & verify.

For degreeing I always use .050" on opening & closing ramps - calculating lobe centre, not max lift.


I have never used a stop. I use the dial indicator and degree wheel. I can find exact TDC while most guys are sinking with the stop.
Why not use a stop?
The stop enters all the variables in one motion. Wouldn't do otherwise.
GURU is only a name.
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Re: ICL vs. .050” Cam Degreeing Methods

Post by statsystems » Mon Jul 09, 2018 10:22 pm

Warp Speed wrote:
Mon Jul 09, 2018 9:58 pm
statsystems wrote:
Mon Jul 09, 2018 9:06 pm
KnightEngines wrote:
Mon Jul 09, 2018 8:07 pm
How does everyone else locate exact TDC?

My method is to use a piston stop - plate that bolts to the deck with a large dia bolt in the middle, set to stop the piston roughly 30 deg from TDC, wind the motor over both ways & split the difference, set the degree wheel pointer & verify.

For degreeing I always use .050" on opening & closing ramps - calculating lobe centre, not max lift.


I have never used a stop. I use the dial indicator and degree wheel. I can find exact TDC while most guys are sinking with the stop.
Why not use a stop?

I can do it faster without a stop. And just as accurate. So I don't bother with it.

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Re: ICL vs. .050” Cam Degreeing Methods

Post by Warp Speed » Tue Jul 10, 2018 5:19 am

statsystems wrote:
Mon Jul 09, 2018 10:22 pm
Warp Speed wrote:
Mon Jul 09, 2018 9:58 pm
statsystems wrote:
Mon Jul 09, 2018 9:06 pm




I have never used a stop. I use the dial indicator and degree wheel. I can find exact TDC while most guys are sinking with the stop.
Why not use a stop?

I can do it faster without a stop. And just as accurate. So I don't bother with it.
Probably not, but then, just as in measuring, it comes down to the size of the wheel and the resolution of the gauge.
So please explain your gauge method?

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