Advanced Question
12-09-2001, 08:41 PM
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Advanced Question
After the recent purchase of my 951, I felt it prudent to change the cam/timing belts.
In removing the belts, I noticed that the cam belt appeared to be one notch advanced? (cam mark back from housting mark, toward 11 o'clock facing gear). After installing the new belt (with timing marks indexed properly) I now feel that the car is not as fast.
Could this be possible or am I just getting used to the acceleration?
In removing the belts, I noticed that the cam belt appeared to be one notch advanced? (cam mark back from housting mark, toward 11 o'clock facing gear). After installing the new belt (with timing marks indexed properly) I now feel that the car is not as fast.
Could this be possible or am I just getting used to the acceleration?
12-10-2001, 06:16 AM
#2
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Hi Bill!
Did you re-check/re-tension the belt after a couple thousand miles? Is it still right on?
An advanced cam would actually give you more high-end power (5000rpm+). With the dropping torque curves of our cars, advancing the cam may not be a bad idea. Check out Farzaan's Dyno Day with dyno chart comparisons of aftermarket chips.
But one tooth is may be too much (about 11-degrees). Most people use about 5-degrees of advance, but you'll need an adjustable cam-gear for that.
And most likely, you're getting used to the speed! Have to take another hit of the go-fast crack-pipe (NSX-files website->Chapter 60)!
Did you re-check/re-tension the belt after a couple thousand miles? Is it still right on?
An advanced cam would actually give you more high-end power (5000rpm+). With the dropping torque curves of our cars, advancing the cam may not be a bad idea. Check out Farzaan's Dyno Day with dyno chart comparisons of aftermarket chips.
But one tooth is may be too much (about 11-degrees). Most people use about 5-degrees of advance, but you'll need an adjustable cam-gear for that.
And most likely, you're getting used to the speed! Have to take another hit of the go-fast crack-pipe (NSX-files website->Chapter 60)!
12-10-2001, 11:38 PM
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Thanks Danno,
Yes I did retension at 1500 mi.
11 degrees advanced sounds like trouble, I think I will keep it at the factory indexing.
In the imortal words of "Tim the Tool Man" I guess I need MORE power! arh arh arh.
Yes I did retension at 1500 mi.
11 degrees advanced sounds like trouble, I think I will keep it at the factory indexing.
In the imortal words of "Tim the Tool Man" I guess I need MORE power! arh arh arh.
12-14-2001, 04:00 PM
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Bill, how did you check the tension? I ask this because to do it properly, you need a special gauge from Porsche and they run about $450... I know because I bought one, but I figured with the money I saved by doing the timing myself, (actually a friend helped) I would save that much anyway AND I would have it for the future. Condisering how important the timing belt is on these cars.. you may want to do the same, if you haven't already.
12-14-2001, 08:00 PM
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how did you check the tension?
I purchased the $450 gauge, except it cost me $500 6 years ago.
I also saw the wisdom in the fact that after just 2 belt changes ($300 each at a local shop)it would pay for itself. I do need to get the calibration tool next as a precaution.
Deni,
Wass up buddy! We need to work on another dash and dine run, like the one that Danno put together, that was great fun! (this time I want to follow YOU....so I get to see you spin).....any ideas?