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May 27, 2005 7:34:11 AM
- cartouche
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Reply to:
Carlos from Spain
Re: Another round of scenic 997S photos
Carlos,
already 1400 km, 1400 insects on the windshield, and one question :
whatever gear engaged, during a linear acceleration, it seems to be a little gap in power between 3600 and 4000 rpm; a light feeling but annoying. I guess it's due to the break-in, the engine beeing not totally "liberated" before 8000-10000 km ?
Do you feel the same phenomenon ?
already 1400 km, 1400 insects on the windshield, and one question :
whatever gear engaged, during a linear acceleration, it seems to be a little gap in power between 3600 and 4000 rpm; a light feeling but annoying. I guess it's due to the break-in, the engine beeing not totally "liberated" before 8000-10000 km ?
Do you feel the same phenomenon ?
May 27, 2005 9:03:12 AM
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zzboba
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Reply to:
Carlos from Spain
Re: Another round of scenic 997S photos
Quote:
FARGO said:
its the valve system
http://www.panix.com/~clay/cayenne/variocam.html
Thanks for the link Fargo (Awesome movie BTW!)
I always thought variocam plus was just the way the "arbre a cames" (sorry don't know the english term) was designed, that would then influence the valve timing management depending engine temperature and load.
Do you know what is the difference between Variocam and Variocam Plus please?
but where is the brake dust?? 
Re: Another round of scenic 997S photos
Quote:
zzboba said:
great, carlos!!
the truly awesome scenery actually draws off the attention from the car
thank you for sharing!
Well, that truly depends on the car, it would be the other way round with something red.
But then, I think drawing attention isn't necessarily what a Porsche is supposed to be.
BTW, great pics, Carlos!
Re: Another round of scenic 997S photos
Quote:
FARGO said:
its the valve system
http://www.panix.com/~clay/cayenne/variocam.html
Well, if it's that, I don't like the feeling of this variocam system.
Precisely on medium revs, when you need a sharp acceleration, it gives you the feeling that the engine breathes with difficulty
Re: Another round of scenic 997S photos
Quote:
cartouche said:Quote:
FARGO said:
its the valve system
http://www.panix.com/~clay/cayenne/variocam.html
Well, if it's that, I don't like the feeling of this variocam system.
Precisely on medium revs, when you need a sharp acceleration, it gives you the feeling that the engine breathes with difficulty
Cartouche,
My car has Variocam plus (996 02) and it definitely does not have a gap in power delivery, a surge yes, but no gap in mid rev.
Maybe it's temporary during break in, otherwise, maybe check with your mechanic?
Re: Another round of scenic 997S photos
Quote:
cartouche said:
Carlos,
already 1400 km, 1400 insects on the windshield, and one question :
whatever gear engaged, during a linear acceleration, it seems to be a little gap in power between 3600 and 4000 rpm; a light feeling but annoying. I guess it's due to the break-in, the engine beeing not totally "liberated" before 8000-10000 km ?
Do you feel the same phenomenon ?
Yep normal Carlos as far as I know..
I spotted this at this rev range on my Demo , it felt like Lag for a very small time frame..
I will learn the strong rev ranges in time on pick up ( 7 months wait
)
throt..
May 27, 2005 12:26:32 PM
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Carlos from Spain
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- Reply to: alin2
Re: Another round of scenic 997S photos
Thanks a lot guys, glad you enjoyed the photos 
Cartouge,
I have not noticed that at all, completely linear from 3000 to 4000 but at 4000rpm the engine starts to pick up more without any previous dips, and the at 5000 even more so with the variocam. What I mean is that there are rps were youn notice that power increases more rapidly but without a drop in power preceeding it, its increaasing through all the rpm range.
Also could be that maybe its because I'm so used to this engine (its basically the same as my 996 but with more HP/Torque), but I will take note of paying special attention b/w 3600-4000rpm and I'll get back to you on it.
Gnil,
there is actually some brake dust but with these wheels I noticed less brake dust build up than with my old Sport Design of my 996, maybe its because of the "open" 5 spoke disegn or maybe because the pads need just more brake-in.
Cartouge,
I have not noticed that at all, completely linear from 3000 to 4000 but at 4000rpm the engine starts to pick up more without any previous dips, and the at 5000 even more so with the variocam. What I mean is that there are rps were youn notice that power increases more rapidly but without a drop in power preceeding it, its increaasing through all the rpm range.
Also could be that maybe its because I'm so used to this engine (its basically the same as my 996 but with more HP/Torque), but I will take note of paying special attention b/w 3600-4000rpm and I'll get back to you on it.
Gnil,
there is actually some brake dust but with these wheels I noticed less brake dust build up than with my old Sport Design of my 996, maybe its because of the "open" 5 spoke disegn or maybe because the pads need just more brake-in.
May 27, 2005 1:03:49 PM
- throt
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Reply to:
Carlos from Spain
May 27, 2005 2:18:58 PM
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Carlos from Spain
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- Reply to: throt
Re: Another round of scenic 997S photos
Quote:
throt said:
Are you going to change the black for the colour crest on the wheels ?..
I don't think I will Throt, I preffer the black crests on the wheels on a black car, blends better, the colored crest also look good though jump out to much because of the color on a black car and grey wheels.In my previous Ocean Blue 996 however I had the colored crests.
May 27, 2005 2:23:29 PM
- Dilinger
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Reply to:
Carlos from Spain
Re: Another round of scenic 997S photos
Quote:
Fanch said:I always thought variocam plus was just the way the "arbre a cames" (sorry don't know the english term) was designed, that would then influence the valve timing management depending engine temperature and load.
Do you know what is the difference between Variocam and Variocam Plus please?
Hi Fanch,
"arbre a cames" = "camshaft" not "camshift" (no offense Ziggy)
I believe Variocam only adjusts intake timing, VariocamPlus adjusts intake and exhaust timing. Maybe someone more geeky than myself can confirm this.
mcdelaug
May 27, 2005 2:40:48 PM
- SoCal Alan
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- Reply to: cartouche
Re: Another round of scenic 997S photos
Quote:
cartouche said:
Carlos,
already 1400 km, 1400 insects on the windshield, and one question :
whatever gear engaged, during a linear acceleration, it seems to be a little gap in power between 3600 and 4000 rpm; a light feeling but annoying. I guess it's due to the break-in, the engine beeing not totally "liberated" before 8000-10000 km ?
Do you feel the same phenomenon ?
Maybe you can take your car to a speed shop to get it dyno'd. It would be interesting to see what it looks like. I'll see if I notice this gap in power on my 997S. You have an 'S', correct?
Re: Another round of scenic 997S photos
Quote:
mcdelaug said:Quote:
Fanch said:I always thought variocam plus was just the way the "arbre a cames" (sorry don't know the english term) was designed, that would then influence the valve timing management depending engine temperature and load.
Do you know what is the difference between Variocam and Variocam Plus please?
Hi Fanch,
"arbre a cames" = "camshaft" not "camshift" (no offense Ziggy)
I believe Variocam only adjusts intake timing, VariocamPlus adjusts intake and exhaust timing. Maybe someone more geeky than myself can confirm this.
mcdelaug
I thought variocam = two positions for camshaft and variocam + = linear ? is that not the difference vs. intake / exhaust?
Cheers
Re: Another round of scenic 997S photos
Quote:
Jeannot said:
I thought variocam = two positions for camshaft and variocam + = linear ? is that not the difference vs. intake / exhaust?
Cheers
OK, I stopped being lazy and actually looked this up. Here's what I've learned.
Variocam, as originally implemented on the 968: a solenoid actuator would press against the timing chain to advance valve timing as engine RPM increased. Apparently there were three stages of advancement in the original Variocam.
Current products (987 for example) have a more sophisticated version of Variocam that relies on a rotary valve at the end of the camshaft to adjust valve timing (no more solenoid driven arm pressing against the timing chain).
Only the intake valves are modulated inthe current version of Variocam.
VariocamPlus: a more complex system of hydraulic tappets driven by a multilobe camshaft that can vary valve lift combined with Variocam's rotary valve system for adjusting valve timing. Only the intake valves are modulated in the current form of VariocamPlus.
So to summarize:
Variocam = timing
VariocamPlus = timing AND lift
Both only modulate the intake valves.
After having read about it, other manufacturers, including Honda and Toyota, appear to have created more sophisticated systems, although they are not used on all of their products.
See these links:
[url=http://www.autozine.org/technical_school/engine/vvt_31.htm]
[url=http://content3.us.porsche.com/prod/911/carrera4s_cabriolet.nsf/usaenglish/engine_transmissionvariocam_plus]
I hope this makes things a little more clear.
mcdelaug
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