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Old 01-13-2022, 01:17 PM
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Default Cam degree question

I installed my comp roller a got From Kauffman yesterday and my Sims precision machine roller bearing timing chain installed straight up as a starting reference point. After I degree the setup it comes in at 108 on the centerline. Cam is ground on a 110, so it's been a number of years for me since I have done one, do I install the bottom gear -2 to get my 110? Thanks guys!

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Old 01-13-2022, 01:46 PM
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Honestly if you are at 108 I would try that. Chain will stretch some and lose a degree or 2 after some miles.

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Old 01-13-2022, 03:18 PM
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Quote:
Originally Posted by Mike Davis View Post
Honestly if you are at 108 I would try that. Chain will stretch some and lose a degree or 2 after some miles.
So you don't think I would be losing any power with that cam timing? I'm running as cast high highports with around 11:01 compression in my 461

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Old 01-13-2022, 03:25 PM
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Can you post a picture of the cam card?

Stan

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Old 01-13-2022, 03:35 PM
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Sure! I will post one when I get home in a couple hrs

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Old 01-13-2022, 05:08 PM
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Here it is. I'm running 1.65 rockers
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Old 01-13-2022, 05:13 PM
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I would leave it at 108. With 304 deg of adv int duration, that's a lot. The intake valve will close late enough, even with 11 to 1 static..

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Old 01-13-2022, 05:20 PM
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Default Lots of opinions, but what about the original question?

We don't do a lot of cam degreeing, but would like to better understand the mechanics of what changes need to be made to move lobe timing. The OP probably would like to know, too. That's why he posted the question.

Would switching the bottom gear to the -2 mark move the cam from 108 to 110?

Thanks.

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Old 01-13-2022, 07:10 PM
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Quote:
Originally Posted by Joe's Garage View Post
We don't do a lot of cam degreeing, but would like to better understand the mechanics of what changes need to be made to move lobe timing. The OP probably would like to know, too. That's why he posted the question.

Would switching the bottom gear to the -2 mark move the cam from 108 to 110?

Thanks.
Theoretically yes.

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Old 01-14-2022, 01:22 AM
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You are fine, run it. My cam came in at 111, supposed to be 112.

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Old 01-14-2022, 10:46 AM
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Well here in another wrench to throw into the gears. I emailed kauffman before I posted up here and he now suggests getting in closer to 106. What exactly would that do for my combination?

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Old 01-14-2022, 11:51 AM
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What is the whole combo? 106 will give it more bottom end and have a narrower power band than a 108.

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Old 01-14-2022, 11:52 AM
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Quote:
Originally Posted by n20ta2 View Post
Here it is. I'm running 1.65 rockers
Thanks for posting the cam card.

Sure wish Pastry Chef (Mike) was not suspended. He would be able to post up the actual lobe curves for these lobes. This would give us a better understanding of what advancing the cam and moving all 4 cam events would do. While advancing the cam does not change how much overlap the cam has it does change how the overlap will work. They are some on PY who like to degree the cam where the intake lifter raise is 0.030" higher than the exhaust ATDC.

Stan

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Old 01-14-2022, 01:34 PM
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Quote:
Originally Posted by Stan Weiss View Post
Thanks for posting the cam card.

Sure wish Pastry Chef (Mike) was not suspended. He would be able to post up the actual lobe curves for these lobes. This would give us a better understanding of what advancing the cam and moving all 4 cam events would do. While advancing the cam does not change how much overlap the cam has it does change how the overlap will work. They are some on PY who like to degree the cam where the intake lifter raise is 0.030" higher than the exhaust ATDC.

Stan
Interesting, it's all nee to me, I have never messed with cam timing other then to match the cam card and I have usually had them spot on eith the card with the dots lined up.

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Old 01-14-2022, 01:38 PM
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Quote:
Originally Posted by Mike Davis View Post
What is the whole combo? 106 will give it more bottom end and have a narrower power band than a 108.
Ok so it's in a 69 gto, all steel. 12 bolt with 3.73 gear, th400 with a continental 3800-4000 stall. Tire is a 295 65 15 Mt radial. Engine is a 461 with as cast highports, zero decked 11:01 compression with 1.65 ratio rockers.. I will be using a northwind intake with either a 950 hp or a 1050 dominator.

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Old 01-14-2022, 01:40 PM
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Should also add this is a matching numbers block with studded 2 bolt mains so I'm not planning on spinning this thing very high. I know I'm limited with my block hp wise.

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Old 01-14-2022, 01:47 PM
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With that converter and gear I would leave it where it's at personally.
I don't think you will see much difference between 108 and 106.

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  #18  
Old 01-14-2022, 03:34 PM
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Quote:
Originally Posted by n20ta2 View Post
Should also add this is a matching numbers block with studded 2 bolt mains so I'm not planning on spinning this thing very high. I know I'm limited with my block hp wise.
Can you put that in terms of RPM?

Stan

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Old 01-14-2022, 05:51 PM
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Safe is probably what 6- 6500?

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Old 01-14-2022, 07:15 PM
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Quote:
Originally Posted by n20ta2 View Post
Safe is probably what 6- 6500?
Thanks. No sure what others think, but with your parts and where I see it making peak power you would need to turn 6500 or so.

Stan

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