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4 Degree Offset Cam Key

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Old 04-02-2013 | 11:58 PM
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Was the 2nd dyno run done with just the offset cam key or did it also have some sort of exhaust mod?
Thanks
Old 04-03-2013 | 12:21 AM
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Edit, nevermind.
Old 04-03-2013 | 12:23 AM
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I have a question, if I put in the 4 degree key in a stock motor would I hurt the performance, until I get the Rogue tune?
Old 04-03-2013 | 12:37 AM
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Originally Posted by pops 83 944
I have a question, if I put in the 4 degree key in a stock motor would I hurt the performance, until I get the Rogue tune?
Would also like to know this.

Also, my father was worried it might have side affects such as burning the exhaust, etc.

Do all the 944 spec racers use advanced timing? If not why? I want more assurance that this mod is all good stuff.
Old 04-03-2013 | 05:17 PM
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Originally Posted by Contadino
Was the 2nd dyno run done with just the offset cam key or did it also have some sort of exhaust mod?
Thanks
Which dyno? I did do a straight-through exhaust, however this was done before the cam-key testing.

Originally Posted by pops 83 944
I have a question, if I put in the 4 degree key in a stock motor would I hurt the performance, until I get the Rogue tune?
The high-RPM hp/tq will not hold as well, but otherwise you should see similar benefits.

Originally Posted by Butters944
Would also like to know this.

Also, my father was worried it might have side affects such as burning the exhaust, etc.

Do all the 944 spec racers use advanced timing? If not why? I want more assurance that this mod is all good stuff.
Burning the exhaust? I assume you mean burning an exhaust valve..? No. The 4º shift is not going to hurt anything. Advancing/retarding the cam is something that people have been doing for a very long time. In-fact, nearly all new cars do this dynamically (computer controlled). They tend to call it something cool, like i-Vtech, Vario-cam, VANOS, VVT, ect.

Just look-up variable-valve-timing for more info on implementations of cam-phasing.

Spec-racers might not use it, because a lot might want/need as much high-RPM power as possible.
Old 04-03-2013 | 07:08 PM
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USA cars have differnt cam timing 2 euro cars which have silghtly more factory out put
Old 04-03-2013 | 08:05 PM
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Originally Posted by t3rra
USA cars have differnt cam timing 2 euro cars which have silghtly more factory out put
Do you have the specs..?

The only cam differences I have only seen are the early vs late.
Old 04-03-2013 | 09:22 PM
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I've got the original cam out of my ROW car at the moment.
If you want, I could get it down to the engine shop to have everything measured up.
Old 04-03-2013 | 09:29 PM
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Originally Posted by Fara
I've got the original cam out of my ROW car at the moment.
If you want, I could get it down to the engine shop to have everything measured up.
If you like.
Though even a part number would suffice.
Old 04-04-2013 | 01:27 AM
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the part numbers are
944 105 155 05 early n/a
944 105 155 09 85.5 on, this has 1mm more lift and 8 degrees more duration on the exhaust lobe only
Old 04-04-2013 | 01:36 AM
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Originally Posted by fred27
the part numbers are
944 105 155 05 early n/a
944 105 155 09 85.5 on, this has 1mm more lift and 8 degrees more duration on the exhaust lobe only
Yep, same cams as State-side...
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Old 04-04-2013 | 03:05 AM
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Would the 4 degree key work for a 16v? I wonder...
Old 03-19-2022 | 12:39 PM
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Hello All,

I have the cam housing off my 87 924S to replace a broken #4 exhaust springs. I’d had a 928 International 4 degree cam key on hand and figured this would be a good time to install it.

My question: has anyone had to file the new key to get it to fit? I have NOT done so yet, no have I applied and light hammer/drift tapping, but it sure looks like the new hi-po key is a hair too long for the (lozenge shaped) recess in the cam’s end.

Wisdom from the gurus would be most appreciated.

kind regards, John
Old 03-19-2022 | 01:20 PM
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Never mind. Put on my bigger-boy trousers and finessed the key with a file.

thanks anyways!

John
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Old 03-22-2022 | 03:29 PM
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Is there another source for an offset key other than 928 Motorsports? $40 seems a bit high for a reengineered $5 OEM part.


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