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-nick
Joined: 16 Nov 2002 Posts: 2699 Location: Cambridge, MA
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Posted: Wed Mar 29, 2006 5:07 am Post subject: Adjustable Timing Gear |
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Are they worth picking up? I've seen pics from a couple folks on here who have them. Is everyone just running a little cam retard to bump the top end? Or just using them to degree the cam in to alignment? How big is the effect with our engines? I want to hear from anyone who has played around them on these cars on the street. Especially so if you're running a 931.
My head has been skimed twice now (that I know of). Not sure how much was taken off each time - they were both done during normal head r&r (no warpage reported). I'm sure my cam timing is running a touch advanced (if I'm visually it right...).
It looks like they're around $100 from VW places (basic A1/2/3 chassis 8V adjustable cam wheel).
Thoughts?
nick |
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bass gt
Joined: 02 Dec 2004 Posts: 971 Location: Johannesburg for now!!
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Posted: Wed Mar 29, 2006 5:40 am Post subject: |
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Nick,
I think for a 931 with some head mods, or skimmed, these have to be worth it. If only to dial in the cam timing to the factory spec. However, as you know, it's quite possible to modify the power delivery, in a minor way, with the cam timing.
Remember, the cam is the heart of the engine. Make it beat to the right time.
Steve |
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Kenodog
Joined: 25 Jun 2003 Posts: 2645 Location: Vancouver,B.C.
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Posted: Wed Mar 29, 2006 3:00 pm Post subject: |
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Nick i've played a little with mine and it does make a big difference.Especially if you dial it alot one way or the other.I will assume that they are all pretty much the same design,mine goes 8 deg either way.This is quite helpful if you're running more than stock boost.Inversely,if you are running stock boost then set it to advance and feel the extra low end pull without worrying to much about detonation.
My original plan was to set the cam gear set to full advance for low rev snap and have an MSD BTM retard by 3 deg per psi. when in full boost to spare me the high end detonation. _________________ 1979 Euro 931, Olive
1981 931, Sabine
1991 Ford Ranger XLT 4x4
1996 Ford E-350 ex-FedEx Van
2014 Mazda CX-5 (Kinderwagon)
2019 KTM 790 Adventure
2024 KLX300
2024 KLX140 |
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morghen
Joined: 21 Jan 2005 Posts: 8868 Location: Romania
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Posted: Wed Mar 29, 2006 11:53 pm Post subject: |
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so to a NA this would be no good ? _________________ https://www.the924.com |
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macBdog
Joined: 16 Aug 2004 Posts: 1111 Location: Brisbane, Australia
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Posted: Thu Mar 30, 2006 9:57 am Post subject: |
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Also what brand are the ones youve got? I have my head off at the moment and wanted to get one but I can't find em for our cars. _________________ 1979 931 with a 350 chev
1973 911E with EFI
p-talk wrote: | I'm still convinced the word 'Porsche' makes people crazy in all kinds of ways |
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ESC944
Joined: 21 May 2004 Posts: 747 Location: FL
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Posted: Thu Mar 30, 2006 2:45 pm Post subject: |
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You can make some strides/gains with an ACG on a NA or Turbo car. ACG= Adjustable Cam Gear.
CONTENT DELETED TO APPEASE NICK
Last edited by ESC944 on Fri Mar 31, 2006 4:33 am; edited 1 time in total |
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flosho
Joined: 01 Jul 2004 Posts: 3155 Location: Eau Claire, Wisconsin
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Posted: Thu Mar 30, 2006 3:10 pm Post subject: |
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Excuse my n00bness on this subject. But it is possible to do valve damage if you adjust the cam gear too far one way correct? How much would a person be able to adjust it to the safe maximum? _________________ [This Space For Rent] |
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macBdog
Joined: 16 Aug 2004 Posts: 1111 Location: Brisbane, Australia
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Posted: Thu Mar 30, 2006 3:22 pm Post subject: |
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Thanks for the write up ESC, good info. Now where can I get one for the 924? You mentioned a company that supplies them for VWs in your post... _________________ 1979 931 with a 350 chev
1973 911E with EFI
p-talk wrote: | I'm still convinced the word 'Porsche' makes people crazy in all kinds of ways |
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ESC944
Joined: 21 May 2004 Posts: 747 Location: FL
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ESC944
Joined: 21 May 2004 Posts: 747 Location: FL
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Posted: Thu Mar 30, 2006 3:35 pm Post subject: |
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Flosho - I would say it is not in "your" best interest to do anything involving valves - your car snacks on those enough already.
As for actual damage - well anything is possible - but in general practice no. |
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flosho
Joined: 01 Jul 2004 Posts: 3155 Location: Eau Claire, Wisconsin
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Posted: Thu Mar 30, 2006 3:46 pm Post subject: |
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ESC944 wrote: | Flosho - I would say it is not in "your" best interest to do anything involving valves - your car snacks on those enough already.
As for actual damage - well anything is possible - but in general practice no. |
Yeah that it does. However my 36$ Genuine Porsche timing belt should solve that..right?
I'm hoping to start building a 931 engine from the block up next fall or winter.. I mean I already got an extra cylinder head... _________________ [This Space For Rent] |
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bass gt
Joined: 02 Dec 2004 Posts: 971 Location: Johannesburg for now!!
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Posted: Thu Mar 30, 2006 5:24 pm Post subject: |
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Guy's,
Piper in the UK make and sell them.
Steve |
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ESC944
Joined: 21 May 2004 Posts: 747 Location: FL
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-nick
Joined: 16 Nov 2002 Posts: 2699 Location: Cambridge, MA
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Posted: Fri Mar 31, 2006 3:26 am Post subject: |
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These thoughts don't seem original to me, but you can decide for yourself.
ESC944 wrote:
"The Basic job of the camshaft is to open and close the intake and exhaust valves at the "proper time" relative to engine position (piston travel) - to charge the combustion chamber and expel burnt gasses. "
Sportcompactcar article:
"Basically, the job of the camshaft is to open and close the intake and exhaust valves at the "proper time" relative to engine position (piston travel) - to charge the combustion chamber and expel burnt gasses."
ESC944 wrote:
"Now in any motor once you've bolted on performance parts, milled the head like Nick or some of the other guys on here, or if you install a lumpy performance cam, etc these things alter the optimum cam timing. Well if you consider factory stock optimal. "
Sportcompactcar article:
"However, once you've bolted on performance parts, milled the head or installed a lumpy performance cam, you also alter the optimum cam timing that most sport compacts prefer. What can you do?"
Last edited by -nick on Tue Apr 04, 2006 6:21 am; edited 1 time in total |
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Chrenan
Joined: 15 Jan 2003 Posts: 3903 Location: Canada
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Posted: Fri Mar 31, 2006 3:29 am Post subject: |
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You should always cite the website you are quoting, it is nice for folks to read the original content as they may get more out of the full text. _________________ 1987 951 - M193 Version for Japan |
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