Dan 8

From what i have read it seems more cost effective and better to turbo than to supercharge the 8 is that correct ?

Daniel

takahashi

If you know the answer .... let me know too.

There is no reliable data outthere and I have not seen anyone done a long track laps to show if the heat issue is solved.

Finger crossed for someone putting a positive outcome.

Revolver

Good to see you're not shy of COW subjects Daniel.

Despite several separate efforts I'm yet to see any convincing evidence that turbo charging is either reliable or more effective than supercharging.

Indeed, I'm happy to stick my neck out and suggest that if turbo charging really was the answer for the Renesis we would have seen an SP model from Mazda Australia by now (whatever the public party line might be).

JDM_RX8

I think turbo will be more effective proven from the RX7 class that Turbo + Rotary engine = AWESOME hehe.. but supercharge will give you uniqueness cause not many rotary out there with supercharge (compare to turbo that is).. this is just my opinion but wouldn't it better off changing the rx8 engine to rx7 series 8 engine rather than bolting on turbo kit if u really want to add turbo to ur 8 please feel to argue hehe

timbo

Hell of a first or second post Dan. Welcome to the forum, BTW.

I don't think we'll really know the answer to that question until warranties start expiring, and we see some serious demand for power upgrades.

One of the obvious benefits of s/c is that done the right way, it can compensate for the NA Renesis's obvious weakness, which is a lack of torque especially at low revs, without introducing any lag problems. But someone will surely correct me about this

Revolver

I think that's a challenge people.

Looking forward to the first guy who does that! Suddenly R/M's S/C kit is looking cheep cheep.

Dan 8

Guys i didnt mean to start a turbo /supercharger thread debate , i am only going by my own observation so far from what i have read and been told .

I have been told that turbo would be far cheaper and also more efficient and reversable ?

Does anyone here have a turboed /supercharged car i could take a ride in ?

I live in Brighton.

Also i believe they may make some changes to the 2007 RX8 MODEL DOES ANYONE KNOW IF THIS IS TRUE ?

Daniel

yiksing

From what I read about the Greddy turbo thus far, its good until it hits around 8000 rpm where the turbo starts to flow less than what the engine is capable of supporting. A bigger turbo is needed for more power but there's no space under the hood unless you do some serious moving. Supercharging on the other hand will be able to provide the power throughout the whole rpm range.

Please correct me if I'm wrong

mirkop

there are a few people out there who have turbo'd their 8, some people wernt impressed with the trust turbo kit and its design,
I believe shortly we will have a turbo kit that will proove that Turboing the 8 is a better option then supercharging, but i think we'll just have to wait and see the figures it produces.

Dan 8

Theres a guy i think in Brisbane / Golcoast area that seems to have a turbo up and running thats producing some decent figures , but is there anyone here in Melbourne ?

daniel

Hymee

iTrader: (1)

Archie from Mazfix in Brisbane has done his RX-8 with a Turbo, and got some decent figures. I heard form someone he wasn't planning on releasing it as a kit, but rather offering it as a workshop (in house) fitting. I do know the had to fabricate their own engine mount, but I am unable to attest to the quality of that fairly critical component.

There is not one best. Yes, you can get good power from a turbo, the cost depending on the quality of components chosen, the quality of the management system chosen, and the complexity of the installation.

In my opinion, if you size a turbo for big numbers that is fine, but at the penalty of lag. How much lag depends on the quaility/cost of the turbo. But for an engine that is widely critisied for lacking low end pulling power, the turbo can't help much without sacrifcing top end.

For me, I have made my feelings known why I chose to go down the positive displacement supercharger route. Not a turbo or a centrifugal s/c. And although we are doing more work on it to get it into a production reality, the initial two protoypes showed it does indeed provide a bucket load of low end grunt, and a real pleasure to drive. Right when you want it: when you open the throttle, not some time later after the turbine spools up or the engine revs rise. In fact, one of the crazy conundrums we face is taming the excess combustion pressures at low RPM's. That can be dangerous, but with first class management and tuning, we have been able to keep things under control so far.

For those interested in reading more about the development of the S/C for the RX-8, please have a look at this comprehensive thread: Hymee gets Supercharged (Part 2)

Enjoy!

Cheers,
Hymee.

takahashi

The wording sound very familiar

Reliable = heat issue? Has someone address that? Maybe it is not a problem - let me know please?

mirkop

thats one of the most important issues, like i said only time will tell, we'll wait and see what happends when everyone has their kits up and running, comparing the two different kits ( turbo and sc ) will be easy when they are side by side.
Im sure both rotor master and who ever has the turbo kit up and running wont mind putting both cars side by side.

takahashi

.... and get an independent judicator (the STiG) to drive it

Revolver

Well we had the opportunity to see both R/M's centrifugal S/C and Hymee's positive displacement S/C on the track at Wakefield last October but the same driver did not drive both so it was difficult to compare the two in that particular environment (which obviously is very different from real world driving).

However the MA turbo car was not tracked and I've not seen lap times or similar from the trubo cars I'm aware of (e.g. Ciao's on the Goldy).

I agree that this is still a time will tell exercise.

mirkop

I think the time will come when we will have the oportunity to see all 3 cars, ( R/Ms , hymees, and caios ) on the same track, same driver, and same amount of laps, pushing the cars as hard as possible, im sure the figures at the end of that excesize wont lie.

takahashi

(The STiG is polishing his helmet)....

We should contact the Top Gear for this one.

Revolver

I agree that eventually we'll see more aftermarket FI kits offered but I think it'll take collaboration between the owners of private cars before we see the kind of back to back, same driver testing you're talking about. Even that will take some doing.

I only know one guy with the R/M kit and he doesn't allow anyone else to drive it. This is understandable for a number of reasons but it certainly doesn't assist with comparison testing.

Unless you can get all 3 (or more) driven by the same driver on the same track or dyno (with the same operator) on the same day and allow for things like temp changes on that magic day, all we can do is assess the claims made by the seller of each kit and try to make sense of any separate testing results that are publicised.

Obviously over time some accepted wisdom will build up but if you're in the market for FI now, it's still a guessing game IMHO.

mirkop

has anyone got any pictures, videos, of the supercharger and turbo kits.

Revolver

Ciao had a video of his turboed car in action. He also posted a number of pics during the development/build stage. Try a search for the relevant thread.

As for the S/C kits. RotorMaster has pics on his website from memory and I think Hymee had some pics in a thread somewhere.

Go look for them.

Hymee

iTrader: (1)

I have heaps of pics and a few videos on my thread.

Hymee gets Supercharged (Part 2)

I expect to have updates after the week following easter.

azzaboynt

hmmm...

All I want for xmas is more torque lower down the rev range. from my understanding, turbo only kicks in after a predetirmined rev.

Anyone catch the top gear segment where they pitted a normal medium sized car against a wrx, launched both in 5th gear (i think). The medium sized car won because the turbo in the wrx took a while to get cranking.

Brettus

iTrader: (2)

have to agree with azzaboynt
Low down torque is what the 8 needs to make it complete for everyday driving.
This idea of pitting the SC & Turbo cars on the track to find out which is quickest is acedemic if you drive mostly on the road.
I'd be exstatic if my 8 had plenty of low down torque plus more at the top end . I am sick of crappy turboed hatches that can be picked up for 10k , being able to keep up with my 8.
From what I read the SC sounds the best bet & I would love to hear from someone who has actually fitted the Rotormatser kit . I would part with the 12k if it gave me as good a car as they make out.

timbo

Yep, that was funny...and illustrated the problem. It was an EVO ...one that had an even larger turbo than standard, which they also tested against a Gallardo on the track and it came out quite well, but Clarkson But they showed the boost issue as you say, by pitting it against a bog std Honda Civic econo hatch...and the Honda won. These types of cars are hard to live with.

I've said it before..oh oh! ....the 8 was never represented as a torque-meister. The figures were clearly published, and these showed the car would drive exactly as it does. You need to keep the revs up and use the gears, so it's a bit of pain in traffic 'cos it won't putter along and then give you the pick up you need when the traffic clears.

If you want to try polar opposites, test drive the Mazda 6MPS...or an even better example...the Pug 407 2.7LV6 diesel twin turbo

takahashi

Have you seen the top gear where JC drives the EVO FQ400 vs the Daihatsu Lenos (or similar)

AT 6th gear 2000 rpm, the Daihatsu (or watever) won the drag! There is such a turbo lag from the EVO - it is just laughable.

Rotormaster will be a good concept kit... except I see a lot of engine lights when I sat in it at Wakefield Park.