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Sharing just for general interest. This is a stack of pulleys. - the bottom is stock 996.1, the middle is Mantissport and the third is Torque Solutions. I find the differences in size interesting.
Was the Torque Solutions only available for the 3.4? Don't find it on their site for an 04 C4S. Was cosidering the RSS one but am wondering if it is actually "worth" it
I went with RSS and really happy, it has been on for a few years now, no issues.
Is pretty good quality, a little bit of weight reduction, but not enough to weaken.
Beware of purchasing a brand with many holes machined in it, they have a tendency to break
Make sure you buy a new crank bolt.
If you track your car, an UDP relieves a lot of stress on ancillaries like power steering pumps etc. If you don’t track, don’t bother. IMHO.
it is not a tack car. Its a weekend play toy. I have no intention on it being a track car. But will admit that once i get the suspension upgrades done and some other things i do plan to join PCA and try some of the track events.
The theory behind them is they create less parasitic drain and let more horsepower get to the wheels. Not a lot, some claim maybe 5hp, but for some, every bit counts.
Do you like more horsepower to the wheels? I do... Then not a waste.
You would have to show me evidence of this hp gain. I track my car and I have found that the UDP has saved me a lot of grief with an over-revving power steering pump and the like (and I do have experience with this type of problem). I think that any power gain is psychological. I could be wrong, it wouldn’t be the first time.
I understand the benefit while at the track, reducing the rpm's going to the ac, alternator, water pump??, etc.is a good thing, I don't think these components like to be at above 6k rpm for an extended period of time. But how do these components deal with the slower rpm while on the street?
There is a ton of information about underdrive crank pulleys all over the internet - for all cars, but many specific to the 996.
The bottom line is that they work, put more horsepower to the wheels, and (according to experts like Jake Raby) the solid ones (where the center is not machined for lightness) are durable. Many have reported sustained long term use on street and track.
And if for some reason you don't believe them, even Jake Raby has posted in the past:
"Time and time again this install gives us the largest net power increase of any other bolt on.. I've installed a 3,000 dollar muffler and set of headers in the past and haven't gained as much power as this pulley provides.
Glad install went smoothly. The Dremel is the tool for this job when doing the work in-car."
and
"Despite any actual values, this mod is one of the few that can be felt in the driver's seat.
I see 5-7 HP at the wheels and a torque increase of generally 5 lb/ft after the installation on my dyno. What should be more considered is this mod creates more power across the ENTIRE RPM range, so the average HP is increased and thats a much bigger gain on a stop watch or in the driver's seat than just a peak HP gain."
I understand the benefit while at the track, reducing the rpm's going to the ac, alternator, water pump??, etc.is a good thing, I don't think these components like to be at above 6k rpm for an extended period of time. But how do these components deal with the slower rpm while on the street?
From what I've read, anything over 1800 rpm and you are fine. Unless you are in stop and go traffic constantly, or drive like a grandma, I can't imagine how that would be an issue.
02-03-2019, 05:29 PM
Visual comparison of underdrive pulleys
