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Cam timing

Old Feb 4, 2006 | 03:45 PM
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Default Cam timing

I bought one of Porken's fancy cam timing tools a while back and am finally getting around to using it. My passenger side cam out exactly at 0 advance and the driver's side was about .5 degree advanced. Not bad for both cams to be within .5 degrees of each other. The tool is really easy to use.

I have a '88 S4 with an automatic transmission. What is the best cam timing for this car? I remember Porken stating that on his early 80s automatic that an advance of about 4 degrees woke everything up. That is a different motor and transmission than the S4. Does anyone have any opinions about the S4 timing? It is not a race car, so top speed is not a necessity. Also, does anyone know if 0 degree advance is stock for the S4? I thought I remember reading that the GT was about 2 degree advance.

Thanks
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Old Feb 4, 2006 | 06:13 PM
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How did you like using the Porken Tool? I have one but have not yet tried it.

Harvey
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Old Feb 4, 2006 | 07:12 PM
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BerNard94, I disagree. While you're right that the only way to set the cams if they've been adjusted after the factory is to use a dial gauge, what PorKens tool does is allow you to vary the cam timing very specifically advanced or retarded to your exact specs. PorKen states in his instructions to record where the cams are indexed before you start so you can go back to that exact reading again. Byrdmans cams were 1/2 degree off from the factory and I'm sure that is the exact proper factory setting. He can now advance or retard each cam precisely how much he wants to and return it to the exact factory setting whenever he wants. That's the beauty of the tool. In my case in looking at the old records from my PO the last time the timing belt had been changed the mechanic wrote down that he had advanced the cams 5 degrees. Without removing the cam covers and using a dial gauge or using PorKens tool (which wasn't available back then) I don't know how he could have done that. As it turns out my cams were 13 crank degrees off from each other. For the time until I can use a dial gauge to find out exactly where each should be I used the tool to put them equal to each other. My GT is now running much stronger and I couldn't have done it without PorKens tool.
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Old Feb 4, 2006 | 07:45 PM
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Originally Posted by cfc928gt
.... As it turns out my cams were 13 crank degrees off from each other. For the time until I can use a dial gauge to find out exactly where each should be I used the tool to put them equal to each other. My GT is now running much stronger and I couldn't have done it without PorKens tool.
13 crank deg!! Good catch; however @ 7.5 cam deg/tooth, looks as if your PO missed the index marks by a full tooth on the TB install. Aside from the obvious merits of the tool, is that what the timing marks indicated?
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Old Feb 4, 2006 | 07:55 PM
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Garth, the timing marks were spot on. IIRC the right side was retarded about 2.5 degrees and the drivers side was advanced 4 degrees. That 6.5 degree cam difference translates into 13 degree crank rotation. Since I don't really know what the spot on factory setting is without using a dial indicator I set them both at 2.5 degrees retarded. I'd read somewhere that retarding the cams helps upper end so I thought I'd try it. One of these days I'll index them properly.
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Old Feb 4, 2006 | 08:09 PM
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Thanks cfc. It still sounds as if the correction made was a full tooth retarded on the left cam set to achieve equality. Hummmm, I'll go away to think about that - it makes my head hurt and it's saturday night: I must pour out a cure .. over ice
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Old Feb 4, 2006 | 09:26 PM
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Mike,

I've read that the 32V's are more sensitive to adjustment. I would try (2) or maybe (3) degrees cam advance, and see how it feels.

I'm only running (2) degrees, so I can run regular gas, but there is a noticeable difference with just that amount.
...

BerNard94,

No tool for you!

Actually, it doesn't matter because they are all gone. I'm not going to make any more, unless there's a group of (10) who want some.
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Old Feb 4, 2006 | 10:54 PM
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Porken,
Are you running 2 degrees advance on each cam, or a total of 2 at the crank (1 degree each)?
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Old Feb 5, 2006 | 12:14 AM
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Mike,

(2) degrees at the cams, or (4) degree crank is what I'm running now.

(I got in the habit of saying cam or crank degrees, because of the confusion.)
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Old Feb 5, 2006 | 12:43 AM
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Originally Posted by PorKen
Actually, it doesn't matter because they are all gone. I'm not going to make any more, unless there's a group of (10) who want some.
f*cksicles

Oh well, whenever you get the demand, I need two (one for the 81 and the 79). I'm sure I could talk my neighbor into a set for his 84. So right now you have 3 potential orders.
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Old Feb 5, 2006 | 08:41 AM
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Originally Posted by Hacker-Pschorr
f*cksicles

Oh well, whenever you get the demand, I need two (one for the 81 and the 79). I'm sure I could talk my neighbor into a set for his 84. So right now you have 3 potential orders.
Why not ask those that have them to borrow or "rent" one? Unfortunately, mine is already out on loan.
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Old Feb 5, 2006 | 01:54 PM
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So back to Byrdmans original question. Is there more power to be gained by advancing or retarding the cams? I assume it depends on the year, i.e. my '89 GT cams open and close much more aggressively already. IIRC Mark Kibort advanced his 'new' 85 cams and got a lot more top end power. What is the consensous from the experts?
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Old Feb 5, 2006 | 02:09 PM
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I would have a set also.

Count=4
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Old Feb 5, 2006 | 02:19 PM
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Sorry to hijack again!

Note that Hacker is talking about 16V to 32V conversions - I only need (5) of those for a run, (the price depends on if 928Intl has enough used gear hubs).

The 32V indicators would need at least (10) separate orders.
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Old Feb 5, 2006 | 03:18 PM
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I have timed 3 4valve engines with the dial indicator method and then tested Porkens timingtool. In each case, the tool was within 1/2 degree. I won't waste the time of doing it the old way again.
Thanks again, Ken for a fabulous tool.
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