The supercharger does indeed run off the main drive pulley of the engine, but the power necessary to spin the charger is minimal. You air conditioner compressor takes more to spin than does the SC. During normal operation and even cruising the highway at 130 mph or 70 mph or 150 mph, the boost is NOT getting into the engine and therefore no additional stress is on the engine. The only time that boost is introduced to the engine is at or near WOT. As long as there is vacuum in the engine, there is no boost and therefore no additional stress is placed on the engine than a NA engine. Therefore, there is no more stress on the engine than a turbo would demand. There is also less heat introduced to the emgine than a turbo.

 

Right back at you pal- other than being a horizontally opposed 6 cyl. the 996NA is very different fromt the 996TT. You're a fool if you think that the case design and internals of the na engine will with stand 80 to 130 additional horsepower for a long period of time, even tuned properly. The 996 and boxster engine types have not proven to be the most durable of engines at stock hp levels. The 993, 996TT and GT3 case designs have been proven durable up to a certain point. This is the same basic case Porsche has used in racing for years. If Porsche thought the 996NA engine were durable enough for high hp applications they would have saved themselves massive costs and used it for the TT. Porsche does not use this case design base for their race cars- think about it. The rods are not as good as the TT either (granted those are needing to be replaced on 600plus hp TT engines).
The peak power on the supercharged application is at or around 7200 rpms. As the 996NA is a wet sump system, no, it doesn't have anything to do with hp but with durability. It can be susceptible to cavitation/frothing where the TT/GT3 engine has an internal dry sump pump and does not have this problem.
Rods, bearings, pistons are experiencing a higher effective compression ratio at an eqivalent boost level as a TT due to starting with high comp. pistons.
Bottom line is that if someone wants a durable engine for the long term, IMO SC the 996NA is not the best idea

 

It is obvious that you know nothing about the 996 SC setup. The maximum boost is not at 7200 rpm, but a lesser 6800. Secondly, the amount of HP in a car has absolutely no effect on oil pressure...good or bad. I think the only cavitaiion is your confusion and ignorance about the operation of a superchargered system. The rods are made of the same material (titanium) as the Turbos'. Finally, I run a HIGHER effective compression ratio than the stock turbo.

Rather than trying to get your answers from misc. web sites, try tearing a few engines apart and rebuilding them. Try running Sc'd cars for more than 30 years. Maybe then you can speak intelligently on the subject. You do a disfavor to those looking for accurate info on this board by making such un-informed statements. If you want to post your opinions, fine, but don't try to disguise them as facts.

 

Reread that as i SAID the sc'd car does experience HIGHER effective compression ratio THAN a TT at equivalent boost level. Also, i believe i clarified that NO, the wet sump system does not have anything to do with HP (didn't say anything about oil pressure either) but in durability- there is no substitute for a dry sump type system. Fresh cool plentifull oil to the bearings at all times can't be a bad thing now can it?
It really depends on whos supercharger set up you're talking about and i SAID peak HP not boost-
In extreme situations such as track use through sweepers/turns or on banking such as daytona, homestead a wet sump system at high rpm does have the potential for cavitation or frothing that you would NOT see in a dry sump system- it was a comparrison statement.
Again, if the 996NA engine is so fantastic why do porsche race cars come with some derivative of the 993-GT3-TT case design?

 

Call me silly, but just how many of us our driving our 996 NA like a race car around The Glen on a daily bases, 100% of the time? That would be a big fat zero! I think your point of durability is made in why they use a different platform for racing compared to the everyday cars like NA 996. The durability of that platform is well known and proven. Can they be compared? IMHO, no, I don't think so.

 

All other issues aside woudln't most of you guys be better off selling your 996 N/A and upgrading to a 996 TT and adding a chip? Seems like you would get more power, prestige and reliability at a little more cost. AND that added cost would easily come back in resale value.

 

My motives to supercharge had zero to do with prestige or resale value. My desicion to purchase a Porsche had a BIG FAT ZERO to do with either as well. A shame that this has to be thrown in. Can't anyone do something simply for the passion of it?

 

I don't drive my car for prestige and I didn't buy it for it's resale value and I have no reliability problems such as waiting for spoolup and cooldown or having to add oil every 1000 miles or so. As far as performance.....I suggest that you drive a properly set up SC'd 996 before you think that it might have less performance than a Turbo.

 

I seriously doubt it will outperform a chipped TT. Even if it does it would be marginally faster and exponentially more prone to durability issues.

I haved modded ALL of my cars and have learned that most factory boosted engines can easily handle a little more boost. Most factory N/A cars suffer in one way or another after being boosted.

The Miata is one real exception. Those things seem to do very well boosted, but some reaserch indicates that the miata has a 323GTX block - basically the block was built for a boosted application and then reduced to NA.

The issue is that only time will tell and by the time we can be certain that supercharging the 996 proves reliable, most of us will no longer want a 996.

I KNOW that the 996TT is reliable. I will spend the extra 10K and get a TT and chip it. That way I am not driving some bastardized car that has no resale value and questionable durability. Albeit, with less originality.

 

I just don't find following the crowd that exciting.

 

u have any dyno's of your car and what SC kit are you running?

 

I have no dyno charts and I am running a modified EVO SC system.

 

with all due respect, many don't like porky AWDs w/ less feeling than a nibbler c2

 

I'm keeping my very unique "bastard" and really don't give a rats patootie about resale value. I think you missed that in both of our posts above. Talk to me in two years...then I will be able to give you a REAL WORLD opinion on "durability". Anyone who knows me knows I drive the crap out of my car. If she is still around in two years...let's talk about it then. You all can theorize, guess, blah blah until you are blue in the face...the proof will be in time. It's essential as a consumer to educate yourself before doing something such as SCing your car. There are risks, there are benefits. One has to pay to play and find out where your benefits out weigh any of these "questionable" risks.

 

well said Robyn.