blackenedwings

Mike, I'm curious what you think is more complicated about a turbo? They both work almost identically in terms of shovelling more air into the engine, the tuning and components required to deal with excess heat. The only difference is one uses parasitic power while the other uses exhaust energy. The turbo has a blow off valve to vent excess air, but is not any more complicated.

This just isn't correct... turbos don't have "higher highs" than a supercharger, they have a much larger area under the torque curve, resulting in a faster car all the way across the power band. In terms of torque there isn't even close to a contest. Go look at some of the well tuned turbo dynos to see what the torque band looks like... its incredibly flat and has a lot of area under the curve. That is why even with approximately equal peak horsepower between two equally well set up systems a turboed car will be faster.

Also I wouldn't describe the RX-8s power curve as "flat", as it rises at a steady angle. If you want to see a flat power curve go look at some of the V8 dynos...

Jedi54

iTrader: (7)

Sorry DD2k5! Hope you still have a job today.

Back to our discussion...

mysql

Turbo, because the RX-8 lacks torque.

Red Rex

iTrader: (1)

If you talk to a supercharged RX8 owner long enough, you'll want a supercharger.
If you talk to a turbocharged RX8 owner long enough, you'll want a turbocharger.

Both have ups and downs but I don't think its any contest as to which will perform better: the turbocharger.

mysql

SC vs TC is kind of like arguing if a car is better than a truck.

It all depends on context, budget, and your goals.

If you were to ask me, is the $3000 greddy kit better than a $5000 sc kit? I'd say go for the SC, if the money was not a concern.

However, once you get into any turbo kit above the greddy level, I'd recommend the turbo - with the caveat that the turbo is also properly sized. There are a ton of threads on this topic, but suffice to say that I've had quite a bit more budget for toys on my RX-8 than the average user, and at every step of the way, considering all available options, I've purchased turbo kits.

The funny thing is that people go towards the SC because they think SC = torque, but the SC kits give you less torque. What you end up with, is instant on boost, but that is nullified by a properly sized turbo. So your real world gains are not as real world as you might think. You just end up with less flexibility. That's OK if you're a numbskull with no self control and need a system that isn't easily adjusted. I like to think that not everyone needs to be babysat to that degree.

Texak

haha!! This is great. Everyone knows what a Fail this is, yet 60 people (including myself) took the pole!!

Red Rex

iTrader: (1)

Ouch lol

Well the market for turbochargers for our cars has shrunked quite a bit. We're down what four kits? The three from Mazsport and the MM GReddy upgrade. Mysql if you could do it all over again with the current options available today what would you do? This offer goes out to any force fed RX8 owner. We can sit here and argue theory all day or get feedback from people who have actually been there, done that, and got the T-****.

mysql

AccessPort all the way for fuel management. No question about it's superiority if properly tuned.

I still like MM's kit.

BUT if I had to define my dream kit, it would be top mount (maintenance reasons, not bling), with an external wastegate. That is exactly what I was setting up, but I sold the parts because I'm purchasing another house in a few months (Yes, it's a lame excuse, but it happens to be true).


One thing I wanted to mention, is that people cannot directly compare some kits. A greddy at 9 psi is not close to MM's kit at 9 psi. At the same time, MM's kit at 9 is no where close to it running at 11 psi. The car's characteristics change drastically. You cannot drive the same way you used to. For example, when NA, or even with GReddy kit, you can floor it, and just sit there and watch. With MM's at 11 psi, you end up doing partial throttle a lot because you have a lot more power on tap, and you have to watch for kicking on traction control. It's unfortunate that none of my videos can even remotely show the difference ... so your best bet is to ride with someone who has their car setup properly.

DailyDriver2k5

I made it out the meeting with just a few funny looks , women noticed the acai-berry wet stain on my shirt. Boss made funny of me and asked, If I have a bottom lip?! And proceeded to laugh obnoxiously about it, I am glad somebody got some humor out of it! LOL!


Back on topic...
I was thinking about adding a Turbo to my 8, was looking at the Greddy Kit,does that kit come with a tuned ecu or will I still have to get my ecu retuned?

Also if you any of you guys have this kit let me know the pro's and cons, or is it even worth buying!

I know i can search, but its Friday, i have acai berry vitamin water on my shirt and i feeling slightly lazy right now, so give me some slack!

mysql

GReddy is the most base level kit available.

Many of the components are sub-par, including the turbo, the couplers, the clamps, and the fuel management system.

If you want a SAFE setup, you'll want to upgrade pretty much everything but the aluminum pipes and manifold. That isn't to say that you can't get the greddy kit working safely, but more that the components will last an unknown amount of time before failing.

At the very least, get the accessport, a bov, and gauges (afr, boost, fp)

Rotr8

iTrader: (2)

thats because the intercooler is an air to water,,, Some people have a hard time locating it visually because they dont see a big front mount,,, the system uses coolers in the front(stated oil coolers) to cool the coolant that is fed to the air to water cooler...

RIWWP

iTrader: (2)

I 100% agree with you that in this frame of reference, they are identical. excepting only their propulsion method. The complication I was refering to is the kit as a whole process from start to finish, which you mention in previous posts:

Again, the entire set-up process start to finish is indeed more complicated. More complicated doesn't automatically mean failure, I get that. Just saying with more complication and more factors to manage, there comes a higher level of risk in getting something wrong. Mentally, this is something I would be willing to work with, but financially, even once I am able to risk my engine financially, I doubt I will be far enough in the clear to be comfortable with an increased risk when there are less risky and still very appealing options. Again, my opinion, my situation, I am hardly going to try to force it on anyone. You know how I bought my 8, and know this isn't just a "I don't want to do my homework" line of thought.



My references here are coming from the Hymee dyno chart. The difference between minimum and maximum torque is only about ~40ft lbs. I haven't seen a Pettit chart to see if it is similarly flat. I understand that the horsepower 'curve' is always climbing at a rise. The T/C dyno charts have a much wider swing between high and low, even if it averages higher. Trust me, I haven't paid more than a passing glance at the peak numbers, because peak doesn't mean anything to me.

blackenedwings

If nobody has listened to any of my comments at least listen to mysql, he really does know what he is talking about. Good to see you on the forum mysql, its been a while. Your setup was one of the main motivators for the kit I've assembled. OEM-like drivability with a stupid amount of power on tap ftw.

blackenedwings

Oh I know you do your homework Mike, and I certainly agree about getting a turbo setup being more "complicated" in terms of piecing a kit together. Most people when they say complicated they are referencing some unknown mechanical difference. I'm hoping the SFR turbo kit will be tunable by AccessPORT, as they make a really nice kit and the top-mount location would allow a more properly sized turbo than the 3071R. When Jeff picked the 3071R he was working with the constraint of the low mount GReddy manifold. As far as the torque curve a properly tuned turbo setup will have a very flat curve with a slight "bubble" and will be significantly higher than the equivalent boost with a S/C. If there was a company offering a turbo kit with the same support and quality as Pettit I don't think there would be a question about which form of FI to choose.

RIWWP

iTrader: (2)

100% agree. Because then the only variable is efficiency really

Edit:
It is the entire package to me that lends so much weight. Right now, watching people piece together turbo kits and the problems they are having with getting everything to mesh properly...or getting proper pieces after they selected them...is a massive turnoff. I applaud those of you that are, and I respect your decisions and dedication. It just feels too much like settling for something because of performance when you could spend a bit more for a bit less performance and no headache.

Headache-free means alot to me.

Rotr8

iTrader: (2)

my install was 2 1/2 days after opening the box, and that was because I wanted to paint a couple things before reinstalling them,,,
Next time your in MD come on over and I show ya my setup and we can take a ride, by then Aaron should have his TC installed and it will be good for you to compare,

blackenedwings

: It's going to take me some time to get mine set up the way I want it, but once my meth kit is in and I'm dyno tuned I think I will have a seriously nice setup. I think you and I will be the two most modified 8s in MD?

Red Rex

iTrader: (1)

Could we perhaps compare the Esmeril turbo kit and the Pettit supercharger both tuned to around 300 whp? What the driving characteristics may be like? They both cost roughly the same. Pros and cons. Comparing superchargers and turbochargers is a pretty broad survey.

blackenedwings

The problem with that comparison is that would be assuming the Esmeril kit is the same quality as the Pettit kit, which everyone knows it isn't. The Esmeril kit has done some good work with pushing the Renesis, but the turbo is not only a cheap piece of eBay junk by all accounts, it is WAY too oversized for the RX-8. As I said before, one of the biggest issues with a turbo setup is a properly sized turbo. There is currently no off the shelf turbo kit that is as well put together or reliable as the Pettit setup. If someone doesn't want to have to build their own kit, superchargers are a great option because of good vendors, not because of the inherant benefits of the technology.

Red Rex

iTrader: (1)

What are the down sides of the Esmeril turbo? We know for intance that in the GReddy turbo that the journal bearings suck, the wastegate sucks, the oil lines suck, pretty much everything about the kit sucks. You would have to eventually replace just about everything to make a good kit. Any specifics on the Esmeril kit? If it was just one or two small things that wouldn't be so horrible as compared to the GReddy kit.

Red Rex

iTrader: (1)

Small threadjack but is there anyway to cheat on an emmisions test? I'm joining the Navy in less than two months and am REALLY hoping to get stationed in Florida where they don't have emmission testing, but if I do get stationed where they have them is there anyway to cheat a force fed RX8 into passing without removing the whole kit?

Could you possibly remove the belt from the supercharger, return the stock cat, and set your tune back to stock? You would probably limp to the shop and back but its probably less of a pain in the *** than removing and reinstalling your entire kit every year. I'm not sure what you would do for a turbocharger. Leave the wastegate wide open, return stock cat and tune?

blackenedwings

Just put the stock cat in before heading to emissions, and use the AccessPORT to disable the CEL.

1.3L

Nitrous oxide.

-1.3L

Rotr8

iTrader: (2)

My RP Cat doesnt throw a CEL....

blackenedwings

Actually its funny my Racing Beat midpipe didn't throw a CEL even when I was on the stock tune with no AP installed... and it smells horrible, so I don't know whats wrong with my O2 sensor, but it doesn't appear to be doing its job lol.