RS Cam's
08-09-2008, 01:34 AM
#16
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FYI - Kevin is putting in slightly modified RS cams into my new twin plug 3.8L solid lifter motor. I like the idea of a smoother power band for track work; over the GT2 cams, which I'm sure are a fun kick in the pants!
08-09-2008, 02:57 AM
#17
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There are as many choices of camshafts as names out there. 
This is just like saying I have hybrid Garretts and I highly recommend them as they give you great "area under the curve", it is too broad of a statement and does not make sense. Who built them, what A/R, what specs, what components, what engine hardware goes with them, what boost, what ECU tune, what cams, etc..
The same applies to cams, there is no "this is great for the street", this is for 60-130, this is great for 5-60mph It all depends what grind, what hardware, what tunei goes with it and what usage.
The factory "GT2" camshaft alone has at least three different specs that I know of, from street with hydraulic lifters to wild race cams with mechanical, the "RS" is exactly the same, some of them require mechanical rockers others don't. Some of them hold idle at 850RPM, others at 1500RPM.
It all goes together, cams, timing, compression, turbo choice, intake, exhaust etc.. Hence why it is so important to have a custom tune. No one can look at a cam, and say, this will be the best option, it goes with testing and experience with similar builds, and optimizing on the dyno, or just as well by looking at what others did and do exactly the same.
Lack of bottom end response with the GT2 cams is a myth, you find RS cams that are much more aggressive.
So I would not get too hung up about nomenclatures, an RS cam for two different tuners can have night and day differences, unless we talk about the profile of the cam, each one might be talking about a different one and with different hardware and comparing apples to oranges.
This is just like saying I have hybrid Garretts and I highly recommend them as they give you great "area under the curve", it is too broad of a statement and does not make sense. Who built them, what A/R, what specs, what components, what engine hardware goes with them, what boost, what ECU tune, what cams, etc..
The same applies to cams, there is no "this is great for the street", this is for 60-130, this is great for 5-60mph
It all depends what grind, what hardware, what tunei goes with it and what usage.The factory "GT2" camshaft alone has at least three different specs that I know of, from street with hydraulic lifters to wild race cams with mechanical, the "RS" is exactly the same, some of them require mechanical rockers others don't. Some of them hold idle at 850RPM, others at 1500RPM.
It all goes together, cams, timing, compression, turbo choice, intake, exhaust etc.. Hence why it is so important to have a custom tune. No one can look at a cam, and say, this will be the best option, it goes with testing and experience with similar builds, and optimizing on the dyno, or just as well by looking at what others did and do exactly the same.
Lack of bottom end response with the GT2 cams is a myth, you find RS cams that are much more aggressive.
So I would not get too hung up about nomenclatures, an RS cam for two different tuners can have night and day differences, unless we talk about the profile of the cam, each one might be talking about a different one and with different hardware and comparing apples to oranges.
08-09-2008, 01:52 PM
#18
Three Wheelin'
Thread Starter
After doing some reading on rennsports website it looks like the RS 3.8 cam's profile is
993 RS 3.8 (intake) 240° @ .490" (Exhaust) 226° @ .446" and 110° (lobe center). Would be interesting to see what the stock 993tt cams are so that we can gauge the difference between the two.
Now I'm trying to track down the part number. Anyone have them on hand by chance?
993 RS 3.8 (intake) 240° @ .490" (Exhaust) 226° @ .446" and 110° (lobe center). Would be interesting to see what the stock 993tt cams are so that we can gauge the difference between the two.
Now I'm trying to track down the part number. Anyone have them on hand by chance?
08-10-2008, 10:47 AM
#21
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08-12-2008, 07:25 PM
#24
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springs
I'm running Aase springs and Ti retainers from Steve Weiner simply because I wanted a bit more high rpm safety.
I think that Schrick also do an uprated spring kit.
Alternatively the stock springs are probably fine
Steve
I think that Schrick also do an uprated spring kit.
Alternatively the stock springs are probably fine
Steve
08-19-2008, 06:25 PM
#25
Three Wheelin'
Thread Starter
Ok now my builder is starting to talk me into GT2 cams 
For those of you that DO have mechanical lifters is it worth the extra power and how often must they be re-set/adjusted? My car will see 500 to 1,000 street miles a year with around 20 - 25 track days. If setting the lash was a once a year thing I could live with it otherwise I'd probably just stick with the hydraulics.
For those of you that DO have mechanical lifters is it worth the extra power and how often must they be re-set/adjusted? My car will see 500 to 1,000 street miles a year with around 20 - 25 track days. If setting the lash was a once a year thing I could live with it otherwise I'd probably just stick with the hydraulics.
08-21-2008, 12:44 AM
#26
As the guys at Kelly Moss would say, it depends on your level of commitment. The short answer is probably once every 2 years at a cost of 800 bucks. If you're like me you'll actually end up spending more on all the other stuff that starts to break at these power levels.
08-21-2008, 11:23 AM
#27
Three Wheelin'
Thread Starter
As the guys at Kelly Moss would say, it depends on your level of commitment. The short answer is probably once every 2 years at a cost of 800 bucks. If you're like me you'll actually end up spending more on all the other stuff that starts to break at these power levels.
Also I'm hosting a private track day at Gingerman Sept 14th if you would like to join us. "Advanced" drivers only, 25 cars max for the event, no run groups, full safety (fire, medical, starter, corner workers) and all the track time you can handle
Shoot me a PM if your interested
08-22-2008, 07:42 PM
#29
Three Wheelin'
Thread Starter
Will you be going the mechanical lifter route with your 3.8 build?
08-22-2008, 08:10 PM
#30
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