This only applies at higher throttle levels and unfortunately full throttle is only what most people think of. At part throttle levels a positive displacement supercharger comes online much faster. If the reverse were true, a turbo would feel like a larger engine rather than a smaller one with a turbo bolted to it. A positive displacement supercharged engine just feels like a larger engine everywhere. I'm not taking anything away from turbos as I've said I do like them. Let's get rid of this bs answer though since under real world driving conditions that is basically anywhere but higher throttle levels this isn't necessarily true.

You never drove with me to work...:FIREdevil

So you saying if you don't like to floor your car and go fast you should get a SC? A SC will feel faster when I'm getting the groceries... But when I floor it, the Turbo will be faster when it matters?

Also this is because you have to build boost with the turbo and your car will drive like normal and get better gas mileage when not in boost. With a sc, it is constant boost whether you want it or not, so more wear on your motor.

Not so much. A quick look in the dyno thread shows us that, after Hymee's claim and graph of +40-50 hp at idle, the closest turbo is MM's making about +30 at around 2700 RPM. I'd use torque figures but Hymee didn't give those.

Let me know how that works out for you.

No actually I'm not saying that. This is a concept that turbo owners typically have a very hard time comprehending hence the responses.

The gas mileage and wear argument is also bs so don't go there.

No, that's why there are bypass valves.

If your foot is mashed into the carpet the entire time, you're doing it wrong.

From a very newb perspective, and speaking in very general terms about the technologies (not specific kits available for the 8) I think this is such a personal preference and personal needs issue that it is impossible to say which one is better.

As far as an SC goes, the main two advantages that come to mind to me are it is impossible to overboost if you size the pulleys correctly, and you aren't sending hot exhaust gases back up around the engine, so to speak. Not that either one is a guarantee of no problems, but as a newb the idea of not having to worry about boost spikes, etc definitely seems appealing.

The turbo generally seems to have the advantages of generating more power, adjustability, less parasitic hp loss (although you will still get some due to increased backpressure) etc.

Ultimately I'd take either if someone threw a free kit at me :)

I think people are underestimating how much throttle is needed to build boost. I only need a little throttle for the pressure to build. It also builds so quickly, "lag" is a non issue.



I can't tell if you are wording things poorly, or have an inaccurate idea how a TC works.

In installing my new turbo, I am really worried about the wastegate air line.

Has anyone replaced this piece of rubber with a braided stainless line?

I don't care what people claim I'm talking about what there is available right now. Until he makes it happen it doesn't exist. Even with the good idle hp increase which doesn't really mean much what is the torque of the finished product? I bet most of the turbo setups have more. I believe a SC is a better fit for a bigger motor that already has good torque.
I only say the good idle power doesn't mean much because with a 4.44 final drive you aren't below 3000 rpms for more than 1 second, making good power from 3000-5000 is good though and the Hymee may make good power there but so do the turbo's and again I bet the turbo's make more torque.

You don't think you can turn up the boost at the drag strip and if needed use race fuel?

As long as you load in the correct tune for the application you can run whatever boost the motor can handle. What is it that won't work out for me?

rotarygod I was just kidding about the gas mileage and engine wear. They are both going to be so close I really don't look at that.

He's probably talking about the front mount turbos (Mazport type 3, Mazsport type 2, Esmeril, SFR, PTP) All of them send exhaust gas to the front of the engine bay and have the downpipe touching the radiator hoses.

Yeah, that's what I was referring to. Routing the exhaust gases through the pipes to drive the turbo when mounted in the engine bay.

With the 4.44 rear end you aren't going to be anywhere in the rev range for very long, what's your point?. The idea is that it makes power right away, not at 5000 rpm. If you look at the turbo dynos, most of them have a bell curve shape suggesting that power doesn't really start to hit until up top.

And besides, in racing, 1 second can be a very long time.

That is true, but in your previous post you made no mention of loading another tune for higher boost. You made it sound like infinite power was just a twist of the knob away, which would have resulted in you picking up bits of Renesis from the staging area.

Keep in mind I can argue in favor of turbos all day too. I can argue both. It really comes down to what you feel is best for your personal needs. I see advantages to superchargers on the street but for a full on race engine I'd go turbo. Again, it depends on the scenario and could make the above statement false. Forced induction in the mountains is an example of where I'd rather have a turbo. It's pretty safe to say that each system will cost you some mileage.

Hymee's supercharger most definitely exists. I've held it. It's not for sale but it exists.

The turbo's you are referring to that don't make power at the bottom, in my opinion are not what would be good for our cars, and there are SC's that do the same thing. I wouldn't like any forced induction that only makes high RPM power. I am referring to the PTP, MM's Greddy upgrade and the Greddy, those kits make good HP right off the bat. It's just a bonus in a turbo setup that a turbo does not require power from the motor to be spun, it just works off the exhaust gas force that has always been there.

My bad about the not referring to a tune, I just figured it was common knowledge and didn't need mention.

And the starting off below 3000 rpms in a drag race... Unless you were clueless on how to get the best 1/4 mile time you would never in any car start below 3000 rpms from a stand still. The only cars that would launch at 3000 or less would be 60's and 70's classic v8's or current automatics.

This is false. It does in fact require power from the engine to spin a turbo. It is using SOME waste energy though which generally makes it more efficient. It is not ONLY using waste energy to spin.

Oh - you forgot the upper eschelon of drag racers stage at an RPM barely above idle.

When you say one might make "more HP and the lower RPM, but what about the Torque", it shows a obvious misunderstanding of a fundamental basic fact. If, at a particular RPM, one setup has twice as much torque as another, then, by definition, it is making twice as much HP. And vice versa.

When the argument degrades to such a point where basic understanding is obviously missing, then I should just tune out.

RG is correct. It is horses for course. My reasons for developing my kit are well documented on this board and in other areas, and include a fair comparison to turbos. IMHO, it is just not what this engine needed. And it is wrong to categorise all SC offerings with the same characteristics. The reason I chose not to go with a centrifugal S/C are similar to why I chose not to go turbo. The car does need grunt at low RPM's to improve it's drivability. The twin-screw, as mentioned earlier, essentially makes this a bigger cube engine when you want it to be. When you have your foot off the gas, it reverts to 1.3 litres. The transition between the 2 is instant. I've posted vids of my hard won findings before, but I'm not going to post them again and again everytime the argument comes up again.

At the time I started, there was nothing available. It might have taken me a while, but I have learned so much, plus I've had to put food on the table as well. If I didn't believe in it I wouldn't have shelled out a fortune in taking it to SSX and setting up a little booth.

If you think I haven't made it happen, have a look around for the numerous vids I have posted.

Cheers,
Hymee.

all i know is that a s.c. gave me enough power to break the rear tires loose with throttle only from 2K---in 1st gear of course ---not 6th. Plus to me they look so cool.
OD

ahh. that makes a little more sense.

just ceramic coat everything and be happy :)

They do look cool.

Snails are ugly... and slow... not made for racing...

or are they?!?!
http://blog.makezine.com/snails_closeup.jpg

The upper echelon of drag racers is not what class we are going to be running in with any of these kits, so I wasn't talking of 1000+ hp cars, I am talking of high hp street cars/daily drivers. If you only have 300 or 400 hp and you start from a dead stop your going to be losing a 1/2 second in your quarter mile time.

Hymee Yours may make power better than the other SC's that are available for the RX-8, I haven't gotten to see what your product does. But at this time with the choices I have... if I had the choice of a Pettit making 195 rwtq and in the same price range(actually $1000 cheaper), the MM Greddy upgrade making 250+ rwtq , both at 307 rwhp I don't think it would be hard to decide which would accelerate better.

The MM makes excellent power very early on and I guarantee you it would pull about 1/2 second faster in the 1/4 mile than the pettit.

Don't get me wrong the Pettit is not a piece of crap or anything and if I just wanted more power and wasnt wanting to be as daring with my car I would get a Pettit. But I want to not have as much of a ceiling on my cars power potential, so I am looking into a PTP turbo kit and one day would like to be able to run 375+ rwhp... I don't want to be limited by my SC. I want to be beating 400+ hp heavier mustangs.

We might as well be arguing the meaning of life, whether God is real or not, and which Jessica is hotter.......


Everyone knows it's Alba, tho ;)

My comments were purely in relation to this statement of yours:

The simple fact remains that a turbo cannot make boost from idle without any lag, and if your are driving around minding your own business at 2000 RPM and you need to put your foot down, it isn't any good either - right where the Renesis needs it, hence my chosen route.

I'm not anti turbo. Heck - I've volunteered plenty of my weekends helping out with 1300+ HP Turbo rotaries at the track, loving every minute. It is just I chose a different setup for my project, and I still believe, after driving both turboed and Hymee'd RX-8's, I had valid reasons.

Cheers,
Hymee.

At face value, it looks like $1000 difference when buying a greddy kit + accessport + MM turbo upgrade, however you end up with two fuel management systems and two turbos. That's at least $1500 in duplicate purchases. So in reality it's ~$2500 less.



That's not turbo lag that you're describing.


No one drives around at 2000 rpm. But for the sake of argument, even if you were and were able to push 10 psi at 2,000 rpm, your power levels would still not be very high. I haven't seen any dyno results from 2,000 rpm .. and at 3,000 rpm we already know the Pettit SC has no advantage over the MM turbo upgrade.

That aside, I'm not arguing over your SC route. I'm just saying that your argument is a bit thin.

I vote Hayden over Jessica!
Obviously more boost.....