Well, I'm using the GT3071 turbo with the lovefab set up. If I'm coasting at 6k rpms at full vaccum and then hammer the gas (this is in 4th gear?, I would say it roughly takes about 1.5 seconds to hit 8psi which is full boost for me, which would take 4-500 rpms to do so. I wouldn't even call it lag because there is literally none, seriously.

What you have to remember is that on a supercharger 9psi S2000, if your cruising at 6k rpms in 4th gear and mash the gas, yes, boost hits right away, but how much? At 6k rpms, boost is only around 2-3 psi with the supercharger, 7k would be 5psi, 8k would be 7psi and 9k would be 9psi, this is called boost dependant.

Look at the scenario, consider that both turbo and supercharged cars are putting down the same rwhp/rwtq at 9psi. Both are in 4th gear at 6k rpms, both mash the gas at the same time. The instant that the race has began, I estimate that the supercharged car will jump maybe a front bumper since the turbo is spoolin up, supercharged is already in boost at 2-3 psi. Now as the they both reach 6.5k rpms, the turbo has finally hit full boost which is 9psi, now the turbo start gaining ground fast because the turbo is at 9psi until redline, supercharger is still boost dependant on rpms. Once they reach 7k rpms, turbo is at 9psi, supercharger is at 5psi, 8k rpms turbo is at 9psi, supercharger is at 7 psi, once they reach redline, supercharger finally hits 9psi but for the last split second...........this is where everyone decides if they want to turbo or supercharged there S2000.

The point is that turbo boost hits alot sooner in the rpms then the supercharger. The sooner the power gets to you, the sooner you will get going. I get full boost at 4k rpms with my turbo, opposed to 1-2 psi at 4k rpms with my supercharger.

I'm not trying to knock the supercharger, I personally love the ease of installation and low maintencee the supercharger offers, it just wasn't for me. I wanted boost right away and only the turbo offered that for now, until the roots type supercharger comes into production (probably never).

Bottom line, the turbo is superior the the centrifugal type superchargers, given they are boost dependant on rpms. The sooner the power comes, the sooner you get moving.

 

What's the latest word on that BRP super?

 

^ Couldn't say it better

 

I agree with everything you said, here and in the rest of your post. Turbo'd S2k's out-accelerate S/C S2k's at a given boost level, in all situations.

However, What I really was trying to bring up is that on the track, I think much of the turbo's advantages over the S/C vanishes. Here's why:

At the track, you're almost never below 6k rpm. (At least I never was when I was out, except for on a VERY tight hairpin). I've found that in track situations, the only time you need more power is in the straights (which the turbo will shine in). However, whenever i'm driving through the twisty infield at the track near where I live, I'm never at full throttle.

In fact, when your in a decreasing radius turn, the LAST thing you want to happen is to have your boost dancing around due to slight throttle inputs.

Not that the S/C doesn't have it's share of problems either. Since it's boost is RPM dependant, a given throttle input gives progressively more boost. However, since the boost response is also *instant* to your right foot, you can learn to compensate for it without much difficulty.

1.5sec of lag really isn't too much on the street, but that can be killer in a tight technical portion of a track. Especially since turbo's have the same boost curve as a centrifugal S/C except that they're time-dependant rather than rpm-dependant. I.e) After you mash the gas, your boost is more like:

+0sec : 0 PSI
+0.5sec : < 1PSI
+1.0sec : < 3 PSI
+1.5sec: 8 PSI

Which is better? Personally, I'm not 100% sure. For the street, turbo, hands down. for the track? I strongly suspect a high-hp S/C car is easier to control than a High-hp turbo car. I'd love to hear dissenting opinions though, and why...

 

^^^You got some points there, but keep in mind that when you exit a corner in let me say 3rd geatr at 6500rpm and floor it, you will see 8psi only at redline, I will see it below 7000rpm. There is literally no lag with the GT30/71

 

You guys are forgetting an important thing here,



1. The S/C will get to power levels where the car is still DAMN fast ( 350 rwhp will beat the pants off 99% of cars on the road )

2. Unlike other cars, if you blow up a shortblock at 600 rwhp, you can't just pick up another factory shortblock for 2k and continue on. No, an S2000 shortblock will be much more expensive to build.

3. The differential is not built to handle this power. I cringe whenever I even think about launching the car. Already been through one, and this one groans as I go around low speed corners something fierce.



Stick with the supercharger. It's very reliable, puts out great power, sounds cool, and there's truely power everywhere. I run 11 psi, and at 4k RPM there is enough "right now" (i.e. not even a fraction of a second of turbo lag) power to put you in the seat.


Turbo is for those with much, much deeper pockets, and for those that haven't heard about the Toyota Supra.

 

Yes, but how often will you be racing at 4k RPM?


Launching at 6k bouncing off my two-step works great to get my S2k off the line. As soon as I get my camera back I can post some videos of the 1/8th mile domination my S2k put on a bunch of S/C'ed Mustangs.

 

This argument will never end. Everyone keeps trying to describe the differences in words but they are a blunt tool.

It you want a true measure of the difference count how many people have gone SC and then upgraded to turbo. Then count how many have gone from turbo to SC. I think you'll find it's pretty conclusive.

 

Hi mate,

would you be so kind and share the 2 step settings with a fellow s2k brother? Can you describe it a bit for me?I am new to AEM and have done only the basic calibration plus A/F tuning based on the map that came from Cody. Did not touch the other features yet, but would love to if you can help

 

Thanks guys for all your comments! I have found it a great wealth of info since I'm still debating whether to buy another 05 s2k to supercharge or go with a 350Z this time around.


Keep the comments coming!

rick