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Cam timing effects, 32V

 
Old 11-18-2011, 02:09 PM
  #46  
BC
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I'm in. I course I said that months ago
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Old 11-18-2011, 02:11 PM
  #47  
Mako 928
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Dear Santa Ken,

I have been very good this year. Having just installed the latest version of chips along with the TQrings I passed California smog last week with flying colors. Included will be a copy of the smog readout along with the last version of chips I am sending back to you.
This has made the evil smog lords of California very happy so I now deserve a new toy. The new Porken timing wrench set will be on my list.

P.S. I have left you some Amsoil instead of cookies as I know your sled is very fast.
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Old 11-18-2011, 03:43 PM
  #48  
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If what I have read over the years is correct, I get the impression that if the belt jumps a tooth then Fred Astaire and Ginger Rodgers will clatter their knee caps together. Given the cam sprocket has something like 50 teeth, that represents just over 7 cam degrees per tooth or say 15 crank degrees.

Colin's experiments have been limited to a [sensible] range of +/- 5 degrees [crank I presume]. Does anyone know exactly how many degrees of advance or retard need to be applied to cause the valves and pistons to interfere?

I would assume that Porsche in their infinite wisdom designed the cam timing adjustment range such that it would not be possible to cause contact at full range of adjustment providing the cams are indexed correctly.

Ken- another interesting looking piece of kit.

Regards

Fred
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Old 11-18-2011, 03:54 PM
  #49  
Mike Frye
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Originally Posted by PorKen View Post
Thanks, all!

If you have to ask...click on my facebook page (<-) for the guesstimate retail.
<snip>
FACEBOOK?!?!?

That's crap! I don't do the Facebook thing. Guess I'll have to wait for it to be stocked at a retailer near me.

Hopefully an announcement will be made when they're available.

If your distributor needs to have a count or will allow for pre-orders maybe a thread asking for interested parties would be appropriate...
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Old 11-18-2011, 03:55 PM
  #50  
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Fred,
1 tooth = 8 deg iirc.
The interference will depend greatly on the camshaft profile.
I have run 0 deg, 5 deg adv, and now 3 deg advance with my cams.
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Old 11-18-2011, 04:00 PM
  #51  
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One cam gear tooth is 7.5 crank degrees.

Folks have gone 2-3 teeth w/o contact w/stock cams.


Originally Posted by Mike Frye View Post
I don't do the Facebook thing.
Don't be timid! It clicks on the (or it gets the hose again).

You don't have to be on the facebooks to see the page.
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Old 11-18-2011, 08:39 PM
  #52  
Bill Ball
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Ken: The Xmas season begins offically the day after Thanksgiving. Get those new parts up for sale!
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Old 11-19-2011, 09:43 AM
  #53  
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In the Northeast it looks like Christmas season has already started.
Bilal
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Old 11-19-2011, 09:57 AM
  #54  
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Originally Posted by PorKen View Post
One cam gear tooth is 7.5 crank degrees.
Ken,

I presume when you are talking about degrees of advance and retard wrt cam timing you are referring crank degrees.

However, with 48 teeth [or whatever] on the cam wheel the 7.5 number logically would be cam degrees surely [i.e. 15 crank degrees]?

Best wishes

Fred
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Old 11-19-2011, 02:59 PM
  #55  
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I should have 7-8 by the first week or so in Dec for the most hard-core early adopters/cam timing ninjas. Since they will be 'pre-production', the price will be lower than the expected retail.

I will post the link on my FB page (<-) when they are ready.



Fred - 24 teeth on the crank pulley, 48 on the cam. Moving the belt one tooth equals ▒15░ on the crank pulley, ▒7.5░ degrees on the camshaft pulley.
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Old 11-19-2011, 04:14 PM
  #56  
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I'm in for one.

Dan
'91 928GT S/C 475hp/460lb.ft
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Old 11-19-2011, 06:51 PM
  #57  
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Ken I'm hardcore as always. Please put me down for your alpha tester list
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Old 11-20-2011, 05:29 AM
  #58  
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Originally Posted by PorKen View Post


Fred - 24 teeth on the crank pulley, 48 on the cam. Moving the belt one tooth equals ▒15░ on the crank pulley, ▒7.5░ degrees on the camshaft pulley.
Ken,

Durrgh!

Thanks for the clarification I think I must have been looking at the other cam wheel instead of the crank - either way head well and truly stuck up *ss on that one!

I was interested in just how much flexibility you have before running into interference issues as it does not take much of a slip to be off quite a bit when you start playing with this part of the system. Although I very much like the 32vr tool and used it to verify my timing was set up correctly I would be very reluctant to try adjustments unless I was way off or out of balance as it were [which I am glad to say I am not thanks to the 32vr].

You new tool may well those concerns redundant.

Best wishes

Fred
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Old 11-20-2011, 12:42 PM
  #59  
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Hey Ken,
I sure as heck want one. ASAP. I will be building the heads and timming them before putting the engine back into the body. I would love to have it before then. Say early December???

Thanks,
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Old 11-20-2011, 12:47 PM
  #60  
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Thanks Ken, sorry but I didn't see your earlier answer. BTW, I could care less about having them plated... Also, I did not get the heads started this week. My grandkids will be here all next week so it will be 2 more weeks now before I get back to it. I am getting a little excited... Man, I will have an 86.5 with virtually 0 miles on engine.... I will be totally Porkenized...I am trying to build as solid an engine as I possibly can so I don't have to do this again in the near future...
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