RotaryShow72

K... So heres my problem... im stuck on deciding what to get..

im looking for a FI system that will give me a nice amount of smooth power but also something that wont screw my engine over or cost over 7000US..

iv heard lots of people with the Greddy kit that have had engine problems after 35,000kms with it bolted on due to the somewhat high PSI they put out

iv also been looking at the pettit super charger but iv also heard SC+Rotaries = The *****

sooo i really dont know what i should do... and i figured you guys here probably knew alot more about this kinda of stuff and rotaries than other forums iv been on asking around... i just want something reasonably priced thats going to give me that extra little boost and wont mess up my engine (if there is such a thing).. im new to the whole rotary engine and all the parts for it and whats good and what isnt so could you please help me out

if anyone has and suggestions i would love to hear them

thanks,
Chris

Jon316G

iTrader: (1)

Oh man... not the best idea to start a new thread about turbos/SCs while the first page of the "Major Horsepower Upgrades" section has MANY threads about turbos/SC.
I know that you are looking for a quick answer, but all the information is provided for you. Just grab some coffee and read read read

Rocketman1976

You new on here so I won't rip into you like a lot of others will.
There are many threads on here about this and some are 200 pges long, try these they are the newer ones. Turbo's are the way to go in my opinion and by the fact of producing more torque than sc, and the whole problem with our motor is torque. Check out the Esmerilracing one its under the $7k and so is Greddy. All the others are over $7k except sc's. Delete this post if you can cause your gonna get ripped

https://www.rx8club.com/series-i-major-horsepower-upgrades-93/esmeril-racing-turbo-kit-released-125203/

https://www.rx8club.com/series-i-major-horsepower-upgrades-93/dyno-comparison-rx-8-turbo-supercharger-etc-115447/

chickenwafer

iTrader: (9)

That's not true. SpeedForceRacing (SFR) Is $5300 for the tuner kit. And the Mazsport type-1 kit is $6999

And to the OP: ANY turbo can "mess up" you engine if it isn't tuned properly, and the same goes for superchargers. It is all in the tuning.

I would recommend reading up all the threads here about the different options you have, and then educating yourself buy learning more about forced induction (FI) and how it all works

Teckfall

Did they drop the price cause I thought the kit was $7999??

Teckfall

Thanks I knew about that but i was talking about the Mazsport type 1 kit

Teckfall

its all good

SoFL_RX8

$5400 without the ECU, add an INT-X at $1500 and your at the price of Mazsport Stage I.

The esmiril racing kit just cam out, dont recall the price, I think its around $5k all said and done, and it seems like a very good kit compaired to the Greddy setup. Do some reasearch on this kit, it might be waht youre looking for.

chickenwafer

iTrader: (9)

It's actually $5299, and add the GReddy E-Manage Ultimate for $685. But you still need larger P2 fuel injectors if you want to hit over 300-rwhp, and an upgraded fuel pump would be nice, too.

And the Esmeril kit is $6495 all said and done.

Phil's 8

iTrader: (3)

Don't believe any bs about s/c and rotaries being the *****. It's the turbo crowd that usually says that but it comes down to a matter of choice. What do you feel comfortable with and what can you afford.

olddragger

iTrader: (3)

SC and the renasis is a good setup. I have heard that because of the difference in the port configuration makes this engine a much better candidate for sc vs turbo. In the end it is a personnel choice. whatever you choose go with a rep company with great customer support
olddragger

sosonic

A lot of the hate for superchargers is coming from turbo fanboys and "traditionalist". There are a lot of positives with going with a twinscrew supercharger and perhaps the upcoming AxialFlow supercharger. I also think the RX-8 and a supercharger is a good match. It can also make FI install and maintenance a bit easier too.

When higher PSI supercharger kits come out, which looks to be relatively soon, than many people will start to have a better view of what superchargers can do for the RX-8. A twinscrew at 10PSI or more should give even the most flaccid man a hard-on.

For all out HP, like 400whp, 500whp, and above, that looks to be turbo. However, 325whp or so is a kind of practical limit for the RX-8 before you need some major engine upgrades. Superchargers should be able to get you to 325Whp. However great lowend power, near instant boost, consistent and even boost, etc... will make for a very exciting daily driver through stop and go traffic, weaving through traffic, and flying around corners. It will be more than fast enough...

Robbie

Please elaborate facts. This smells of opinion.

To the OP a Greddy kit can be very reliable, and make good power for your car for a long time if you get a good tune and you understand how to maintain a car with an aftermarket turbo kit. It actually doesn't have a very high psi stock and it is rather limited because its a smaller turbo.

anewconvert

It has to do with overlap, and as I understand it I think he has it backwards.


At any given pressure with a turbo engine you are going to have a higher exhaust pressure pre-turbine. You cant create more boost than the pressure of the exhaust spinning the turbine. In a high overlap engine, like a standard 13b, that means that there is going to be exhaust reversion as the pressure of the exhaust is greater than the pressure of the intake charge. That is going to result in the exhaust trying to push its way out of the chamber into the intake runners, resulting in less fill time and some exhaust dilution. In a low overlap, or 0 overlap like the Renesis, the exhaust is closed before the chamber is exposed to the intake charge, so reversion is minimized.


With a S/C the intake charge is going to be at a higher pressure than the exhaust, so with greater overlap the intake will actually help to push the exhaust out of the chamber keeping reversion to a minimum (and potentially pushing intake charge out of the exhaust in the process). That results in an ultimately cleaner mixture with less exhaust in the chamber. On a low, or 0, overlap engine the blower cant help as much (or at all) to push the exhaust out making scavenging a greater priority.


This is why there are turbo cams, but most companies dont go out of their way to make blower cams. Turbo's take well to low overlap cams (like stock cams), whereas blowers take well to higher overlap cams, like a good aftermarket NA cam. There is a point where you can have too much overlap. That would result in higher fuel consumption, and less time left to fill the chamber (cylinder) before the intake closes, meaning less power.


Someone correct me if I am wrong.



BC

Rocketman1976

Didn't say SC's were ***** just stated a fact. SC's don't give you as much torque as Turbo's. Put 2 exact same cars up against eachother, Rx-8s, Mustangs or whatever, then put a close to equal SC on one and a turbo on the other, run the same boost and the turbo will walk away from the SC everytime. Research it till your head turns purple and tell me if you ever find a sc kit matched up to a equal or even a little bit lower level or equal turbo, and tell me which one makes more torque every single time.

Pettit SC $6500 265 rwhp 188ft lbs torque at wheels, cheap greddy turbo 1/2 the cost of the Pettit, makes 217 lbs tq at rear wheels with 265 rwhp. The SC is easier to install and the Pettit is a beautiful kit, great engine bay appeal and I'm sure it is great performance, but Turbos eat SC's up.

You want more power in the future turn up the boost or put in bigger turbo $700-$1200. SC you want more? change the pulley to turn it up a little more, once your at the end of that sc's ability you have to sell the whole SC and buy a new one $6000+. You can also get a SC rebuilt with different internals but all in all turbos seem like an endless road to more, and more power.

Go to the drag strip and compare how many cars (the prof drag cars) nowadays have Turbos and how many use SC's I'll bet its 2/3 Turbo.

mac11

iTrader: (1)

Once you get to a certain point a lower power S/C car will walk away from the t/c car due to throttle response and boost lag. Lots of people run turbos that are way to large and lose a lot in the lower half of their powerband and performance because of it.

And this "endelss road" you speak of with larger and larger turbos will eb severly limited by the 10:1 compression ratio Mazda gave you.

dillsrotary

actually the top fuel class (the fastest pro drag class, sub 5 sec runs) uses a roots supercharger


same with the funny car class.......

MazdaManiac

iTrader: (3)

Because they have to. The rules are set up for only that.

This thread rocks! I love it when new, never-before voiced questions are met with even newer and more informative answers from such a capable bunch!

anewconvert

and pics of girls licking each other.


BC

chickenwafer

iTrader: (9)

Care to back up this schmorgasboard of bullshit you just served up?
So you are basically admitting that superchargers are capped at 325-rwhp (which no one has any proof of yet) yet a turbo will make you far MORE rwhp than an s/c ever can dream of, and yet if you size a compressor and turbine PROPERLY you'll still have a stupid low boost threshold (look that word up) and still romp on an s/c'ed car. So how does the s/c win, again?


Or you could just add more fuel and air. I don't get all the whining about compression ratios, it gives us a greater starting point. Go check out turbo Suzuki Hayabusa motorcycles- they have a whopping 13.5:1 compression ratio but still manage over 15 pounds of boost. It's just a matter of getting enough fuel and air inside the motor.

mac11

iTrader: (1)

There are pumps and injectors to get the fuel there and blowers that will give plenty of air. Go strap them on and let me know where the breaking point is.

chickenwafer

iTrader: (9)

We will once we get full engine management worked out, and possibly porting

mac11

iTrader: (1)

I will be very interested in seeing when pulling timing quits making things happen and at what point you need to start going with exotic fuel blends and auxillary injection.