As there are a few blowed up NA motors.

(I gotta hear this story from ya this summer.)

 

.... that actually happened in late 2001.

Sooooo how many people here have had first hand experience with both an SC and a turbo on their S2000 (not at the same time )?

 

I'm guessing the S2000 works a lot like every other 4 stoke internal combustion engine... STRESS doesn't equate to WEAR. My point is that pressure/stress isn't going to wear anything until you exceed the metalurgical properties of the parts being stressed (FATIGUE). Unless we're using the word in the incorrect sense in which wear = bending fracturing rods, cracking sleeves melting pistons which is usually accomplished with EXCESSIVE boost, poor tuning, and a moron behind the wheel and laptop using either a blower or turbochager. Wear is caused by contact between surfaces you can usually point your finger at poor lubricity or an engine that was assembled with poor tolerances which will occur whether it's turbo SC or NA. Kindly explain to me again exactly what in the lower assembly would wear due to stress applied from either a turbo or supercharger? It's all semantics... Even when talking about fatigue I could argue that you could size a turbo to build boost just as slow if not slower than a centrifugal blower if you so desire. But an appropriately sized/tuned turbo at a reasonable boost level on an S2000 will not fatigue the internals to a point where it'll matter (read: break stuff) but will likely have wider, more responsive powerband and better peak power as well given the same boost pressure vs a blower. The better question is are you able to understand that (I'm sure you do, you seem to be an intelligent person albeit a little defensive...)?

 

After analyzing your "averages" I was able to conclude that your "average" turbo S2000 would kick the crap out of your "average" SC or N/A S2000. Again, it's all semantics and as long as rods aren't being "liberated" from the dark confines of the engine block it doesn't really matter IMO. Which brings me to my next question... What's the stock longblock HP/TQ record with and without spacer head gaskets?

 

Wesmaster had first hand experience with both a SC and Turbo. I believe he went through 3 motors before he sold his car last year.

Improper tuning by the local shops seemed to be the main cause for his problems, but he was always on the bleeding edge of the S2000 boost scene.

 

Generally speaking, it will. However, the main point of discussion here is "wear" and if there is any - not to the point of disintegration or failure - just if there is any based on the two profiles. Boost is not just boost and the two types of power output is not the same. You can't extract additional power (and torque) at a lower rpm and think it is not different than extracting that same power (and torque) but at a much higher rpm. There is a toll to be paid. It may not affect reliability (at least in the short term), but there is still a difference.

As for your second question, I don't recall seeing any such comparisons being done.

 

The main problem in RZFD's dimension in conceptual thinking is that it has 'tunnel vision". There is more to wear than just ultimate failure by going well beyond the physical capabilities of the metals. There are infinate number of extremities that become introducted by FI. The main one being force. The crank & rods are pushed creating a smaller film of oil to "hover" between the bearings, piston rings are pushed out more towards cylinder walls causing increased wear, crankcase pressure increases and often results in blow-by which decreases the general octane rating of the combustable compounds within the chamber and can create knocking even for a fraction of a second, increased carbon deposits which ultimately increases compression ratio and also causes wear (wonder why you're suppose to change the oil more frequently on turbo'ed vehicles?), the most important of all IMO would be temperature, and etc etc and etc.

Lower PSI means there isn't as significant increase in temperature. Horsepower is a measure of force. So when you see 7psi and 370whp. It's not as possibly harmful as 12psi and 370whp but it's still the same force being placed just that the temperature is increased through-out the system which is what makes it less efficient (of course there's 2903482093 other factors but ya...that's the jist of it).

BTW, nothing puts more wear than RPM's on a motor...so dont really fret too much about F/I wear if your motor can go upto 8000-9000rpm's and you're not really boosting too high

 

04's made around 20hp more from 4k rpm...I guess due to bigger displacement...? (according to comptech's website)

In fact, it makes power from 4k on up...

I heard that the major complain about the sc was that it doesn't make power until high rpm...I guess this is not really the problem with 04's...and the number was bone stock with sc...so with a header and exhaust=more power...? If this is the case, I think I would definitely go with the comptech...and upgrade the pulley to 6-7 psi and will give me what I want...

 

For high mileage turbo S2000's, I believe Im one of the higher mileage ones out there, at about 7500 miles thus far.
Ive been waiting for my local dyno guy to make his dyno FUNCTIONAL(hes missing RPM pickup), before I turn up the boost. Id like to stay on the stock map sensor, 10.5psi seems to be about the highest you can do. Pair this with C16 and more aggressive timing, Im betting I can tag the 400whp barrier pretty easily. Pump gas, I could probably hit 370whp without worries(and ONLY 93 octane).

On the wear/tear issue, RPM seems to kill motors before boost will. An example is the Cosworth motors in the stateside open-wheel racing; this is from memory of an article I read in Sport Compact Car:
Two years ago they were limited to 2psi, but had to make around 800 hp to be competitive. To do this, they had to spin the motors to 17,000 RPM(I think that was the number). It was rare to have a motor from the field NOT blow during a race. Recently they allowed 6.9psi. They were able to hit the targeted HP much lower in the RPM range, I believe it was around 12,000 RPM. Now motors generally last 3-4 races.
My point for this quotation(attempt at one anyway) is, I rarely rev my car out to 9,000RPM. There is no point, its fun enough just shifting at 5,000RPM partial throttle(and Im usually speeding by then). The SC guys have to rev the PISS out of their cars to feel any significant power over stock. How is this not putting more wear/tear on the motor?
We arent talking about similar driving styles any longer, but have no branched into the turbo vs centrifugal SC powerbands, and why I think turbocharging ownz all

 

7500 miles is nothing considering there have been supercharged S2000s out there exceeding 50K, 60K, 70K. 7500 miles is just barely scratching the surface and does not give grounds to speak in terms of "reliability".

In the confines of what has been discussed in this thread so far, we ARE ("all else being equal"). If you wish to change the parameters of the argument, you must either take it to another thread or clearly state that you wish to change them before initiating your side of the discussion.