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Adjusting Cam timining 86.5

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Old 08-11-2006 | 01:58 PM
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Ken,

Do you have any good contacts that used the tool on their 32V?

I'm debating if I should zero out the left side to match the right or put both advanced 2 deg??


Originally Posted by PorKen
Fausto,

The right side is set retarded slightly per the WSM to compensate for an estimated expansion of the engine at temp, which will advance the valve timing.

I would prefer to adjust the timing of both banks to the left side WSM spec, when the engine is warm instead.
...

Glenn,

If you want to be absolutely positutely perfect, yes. My indicator appears to get it within a cam degree or so. Certainly more accurate than a cam gear change with a Sharpie®.
Old 08-11-2006 | 02:32 PM
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https://rennlist.com/forums/928-forum/242625-porkens-cam-timing-tool-rocks.html
...

Conservatively, with an auto, measured cold, I'd set it to L:2°, R:1.5°. (3°/2.5° is what I'd put on my own car. ) Then check the right one again when the engine is at running temp, to see if it's equal to the left.

You can always use the indicator to go back to zero.
...

I can't figure out why the engines are numbered differently for manual, and M249 (auto). In the old days (pre-emissions?), engines mated to automatics would have had come from the factory with a little valve advance, 2° is common.
...

Side note: hold the [Alt] key and type [0][1][7][6] for '°', Alt-0177 for '±'
Old 08-11-2006 | 02:45 PM
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Originally Posted by Darien Nunn
Any other gear heads out there have any input??

I'm not a gearhead but... I would be careful advancing the timing on a SC'd motor. Very soon you will want to up the boost and you don't want to be worrying about detonation.

Jim H
Old 08-11-2006 | 02:56 PM
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Ken that was 360° in the direction of ± a great post
Old 08-11-2006 | 03:39 PM
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Lightbulb

If I can put my mind around the concept properly, I think you may be one cam tooth retarded, and the cam is advanced to the farthest it can go in the slot. So you are actually 1.5° retarded on the left.

Your compression readings indicate retard on the left, not advance.
...

If (turbo)supercharged, I'd reckon I might go 0°/-0.5°, or even retard some. Especially with 10:1 compression, and no knock sensors.
Old 08-11-2006 | 03:56 PM
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Originally Posted by PorKen
Glenn,

If you want to be absolutely positutely perfect, yes. My indicator appears to get it within a cam degree or so. Certainly more accurate than a cam gear change with a Sharpie®.
I wasn't really thinking about the "accuracy" of your indicator. I just thought you needed to have the cams done per the manual to get a "baseline" from which to use the indicator in the first place. Am I mistaken?
Glenn
Old 08-11-2006 | 04:03 PM
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this sounds like ROG100 cam degree clinic day in the making
Old 08-11-2006 | 04:04 PM
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Glen,
Yes, you are correct.
Jim H

Originally Posted by sharkmeister85
I wasn't really thinking about the "accuracy" of your indicator. I just thought you needed to have the cams done per the manual to get a "baseline" from which to use the indicator in the first place. Am I mistaken?
Glenn
Old 08-11-2006 | 04:18 PM
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Glenn,

I was covering my *** with the WSM thing. I can't say for sure that all the cams were ground precisely in relation to the keyway*, but it seems the cams are within ±1°**. And if you factor in worn chains/tensioners/gears/cam lobes, and the fact that the measurement is taken from the intake cam, but the exhaust cam has the cam gear on it... Anyway, I'm much more confident in my indicator, now.

Without a direct gear drive, the valve timing is never going to be exact. It's not science, mon, it's valve timing.

*Yours may have been made during Oktoberfest!
**I guess more like ±0.5°.
Old 08-11-2006 | 08:04 PM
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What is the function of the spacer in the kit?

Ok..walk us through the steps for setting 2.0 on the driver side and 2.0 on the passenger side. (they are currently as shown in the pics in teh first post)
I honestly cant figure out how this works..sorry
Darien and i are stumped by a few things..partly because we dont want to start loosening bolts that effect timing when we arent 100% of how the tool is to be used or works.

The circled area below is what we are having trouble understanding.
fro example... the driver side..currently at 6.0, we will be taking out timing to a total of 2.0
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Old 08-11-2006 | 08:35 PM
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Do you have a receipt for that tool?
Old 08-11-2006 | 10:23 PM
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Originally Posted by PorKen
Do you have a receipt for that tool?
Ken, as the purchaser of said tool... I have a question (any I don't believe you sent me a receipt ), could you please explain the point that Tony has highlighted? I'm stumped!
Old 08-12-2006 | 01:08 AM
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Do you have a receipt for that tool?
Whatever.
Old 08-12-2006 | 06:29 AM
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First off, you're gonna have to restring the belt. I'm fairly certain the belt is off by a tooth on the left gear. IE the gear needs to be rotated clockwise one tooth (the right gear and crank are not moved), then adjusted.

Can you post a pic of the bare left gear without the indicator, clamp ring, or rotor, so the slots are visible?

I'll go into detail on the adjustment, and use of the spacer tommorrow.

Darien's car does not have a supercharger, correct?
Old 08-12-2006 | 09:07 AM
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Darien's car is supercharged.


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