GReddy or Speed of racing turbo kit
 

basically i want to boost the power of my rx8

i have found 2 turbo kits i'm thinking of

1st is this SPEED OF RACING
This turbo will boost the HP of the motor over 100hp
i contacted the makers and they said i'd have to buy all teh ad ons to get the full 100 hp
the cost would be over $9000


2nd is GReddy's GReddy
this only does around 50Hp much less hp but only at $3,000

what would be the better choice? is the SOR worth it?

There's thousands of threads on this subject. You're very likely going to get flamed for posting on it again.

But I'll break it down to what it really boils down too:

Want a cheap kit that gets good power for a street car get GReddy
Want an expensive kit qith high-quality components that has more potential get SFR

The GReddy kit caps out at an absolute maximum of ~300whp. You can't do any more than that, the turbo is maxed out and you won't see more than 250whp without spending more money.

The SFR kit maxes out much much higher. Can't recall off the top of my head where, but it's way up there. So you can add the options as time goes on and keep bumping up the power as your budget allows.

By the way, it's Speed FORCE Racing.

Also, PTP Motorsports will be coming out with their turbo kit somewhat soon. Will be priced about the middle ($5K for the kit, when all is said & done probably around $7K).

Like Sigma said, it depends what you want to do with it, & how much you are willing to spend.

I got a question for you? How much do you like your RX-8? Why do I ask? Two reason here:

1. If you like your car, and more importantly, your warranty, I would do neither. If more power is a must for you, then you have to balance the equities. Speed Force Racing will add a lot more power, but it also going to cost you a ton of cash, and be much more likely to ruin you engine/drive train. I know it would be fun to put down 350+ at the crank, but I can’t imagine the 8 would be drivable with that much power. The bottom line is that the kit is a bit excessive for the RX-8.
   
   On the other hand Greddy’s kit is substantially cheaper, will require less tuning, and is far less likely to blow your engine. Furthermore it gives the 8 the additional pop the car desperately needs.
   
   In any case, there is a good chance that both kits will substantially lessen the life of your car. This leads into question number 2!
   
   
2. If Speed Force Racing is your ultimate decision I would really reflect on whether the 8 is for you. For the 10 g asking price, you could probably get yourself something of comparable power, without going into the aftermarket, which ultimately means you get to keep your warranty.

In any case good luck with your decision, and let us know how it goes.

What part of Texas you in? I'm in Austin and have the Greddy kit, if your interested for a ride contact me. Also, PTP is in Austin, so you could easily stop by and see where they're at on releasing the higher hp turbo kit.

thank you all for your imput. i've heard rumors that mazda might release a version of the RX8 with a turbo, have you heard anything about this?


also has anyone found any other alternatives to a turbo kit?

I think that concensus on this forum is actually leaning towards the Greddy kit. Espeacilly since the Interceptor-X EMS has come out. They are actually making more horsepower and torque than SFR does with a larger turbo. Plus the fact that since it is a smaller turbo it will spool faster.

The latest news is that they are working on an upgrade to the Greddy kit to supply more air at higher RPM's to sustain the boost.

They are also using other aftermarket turbo pieces (boost controller, bov, etc) so you would have to factor those in as well... All in all though the price would still come in lower than SFR and you would be making more hp/tq.. Sounds like a great option to me.

1. That ain't going to happen. Not anytime in the near future

2. Not yet. A few places are working on Superchargers. Some went by the wayside, some are still in long gestation periods. You have a few people that do nitrous (about a 55 shot), if you want to go that route. The most people are looking at from normally aspirated engines is around 25 hp.

[QUOTE=davefzr]I think that concensus on this forum is actually leaning towards the Greddy kit. Espeacilly since the Interceptor-X EMS has come out. They are actually making more horsepower and torque than SFR does with a larger turbo. Plus the fact that since it is a smaller turbo it will spool faster.


Lets see the dyno chart. PSI for PSI of boost this is impossible! We can add as much fuel and timing as we want and it doesnt matter if the Greddy Super Delux Interceptor-X-Y-Z EMS comes out, it wont change our ability to tune the 8 to the highest level :D With that being said, we are finishing up a few things here and we will have the big HP numbers that will be unattainable with the current Greddy kit or even the one with the Inerceptor-X EMS :p Dont get me wrong the Greddy is a great kit but people are realizing that they want more.That is where companies like us come into play.It might cost more but the rewards are worth it :)

more boost = more lag... if you want top end power, go for it, but if you want to be able to pull earlier, then it won't be great.

Like everyone else has said, it really just depends what you want.

[QUOTE=Pkskull77]I got a question for you? How much do you like your RX-8? Why do I ask? Two reason here:

[*]If you like your car, and more importantly, your warranty, I would do neither. If more power is a must for you, then you have to balance the equities. Speed Force Racing will add a lot more power, but it also going to cost you a ton of cash, and be much more likely to ruin you engine/drive train. I know it would be fun to put down 350+ at the crank, but I can’t imagine the 8 would be drivable with that much power. The bottom line is that the kit is a bit excessive for the RX-8.



If you pump up the car there are always possibilities of catastrophe.We have not had any as of yet, even with our higher power output. As far as I know maybe only one Greddy kit in hundreds has blown. The Renesis is pretty stout. An 8 not being drivable with 350? Well then my friend you havent expereinced what an 8 should feel like :eek: It is so much better to have real passing power at 4000 rpms then at 8500.Lugging around town can be done in higher gears without having to downshift while still having power to spare.There are so many advantages that I cant think of them all.



On the other hand Greddy’s kit is substantially cheaper, will require less tuning, and is far less likely to blow your engine. Furthermore it gives the 8 the additional pop the car desperately needs.



Less tuning? I think you might not understand what you are saying. If any turbo kit is less tuned then you have a time bomb on your hands.Tuning is tuning and I would bet that our tuning might be quite a bit closer out of the Box then the Greddy system.Boost is more likely to blow your engine then anything with a turbo kit. With the Greddy kit making modest power, people get the urge to trun up the boost.You turn up the boost too high and there goes your motor.With our kit, you dont need insane amounts of boost to make excellent power. I mean 8psi and over 300 at the wheels is pretty damn good. You would have to run about 13 psi with the greddy kit to make that type of power unless you are running so much ignition advance that you are on the ragged edge. At that point, it is only a matter of time before she blows :cool:



In any case, there is a good chance that both kits will substantially lessen the life of your car. This leads into question number 2![*]If Speed Force Racing is your ultimate decision I would really reflect on whether the 8 is for you. For the 10 g asking price, you could probably get yourself something of comparable power, without going into the aftermarket, which ultimately means you get to keep your warranty. [/list]


Actually, you can get everything required for 300 WHP for about $7500.

what happen to the guy with the bad o2 sensor???? and all the threads???

do over???

dvno???

beers

[QUOTE=SpeedForceRacing]

ummmm something tells me the car either never ran right or blown motor

That thread got closed due to all of the negative remarks directed at the owner of the RX8 in SFR's hands.. DG1T-8??.. something like that....

isn't that the guy with the blue 8 and veliside kit who keeps posting his trophies from local car shows that nobody cares about?
I might have him confused with somebody else.

Actually that is not the case my friend.We will be finishing it up soon enough.DiGI had some other things to take care of which prevented us from doing what we need to do.I was also in the process of putting the SFR twin-turbo system on my Z. The time thing worked out for both of us but now we are ready to finish.Hopefully we will be dynoing it next week.

The thread got closed which is why I havent been on here as much. I didnt feel like starting a post without some dyno charts,videos,etc.....to back it up. This will happen very soon so the guys that are still interested, I think you will be suprised :D

^^^^^^

great to hear!!!

beers

thanks speedforce

the thing i'm also looking at is at what speeds does a turbo greddy/or SFR kick in, in other words what speeds does a turbo matter???

Turbos don't kick in at speeds they kick in at RPMs.

so basically it works all the time?

[QUOTE=SpeedForceRacing] Sorry SFR, Dave is right.

Watch the video. It's in there:
Video Right Click, Save as

Well now we have the complete turbo system, with injectors, engine management and a fuel pump for 6795$ :) 350whp is definitely achievable now.

No. Turbos spin/spool using exhaust pressure. The layman's explanation is the bigger the turbo the more exhaust it takes to spin it, the smaller the turbo is the less exhaust it takes. Problem with small turbos is though that that limits the amount of compressed air that you can push into the engine, so at high revs in runs out of steam. The disadvantage of a large turbo is that it takes more exhaust to push the turbine blades, hence a term called "lag," where you step on the accelerator & it takes a bit of time before you get more power, or you have to wait until you get to 4000-4500 RPM before the turbo is giving you power/coming on. The advantage of the Greddy is it is a small turbo so in low/mid revs you are getting power, disadvantage is that at high revs you lose steam. The advantage of the other turbo kits being mentioned are they will be using larger turbos, for more peak hp, but that will come on in the mid/high rev range. There are different designs to turbos nowadays to alleviate some of these disadvantages, but this is a very general explanation.

Is it possible to have a pseudo-valve that can be closed and therefore limit the size of the turbo for low-mid rpms and act as a smaller turbo and then at high rpms open completely to get the benefits of a larger turbo?

No the limitation with a small turbo is two-fold. First the compressor side, the issue is in the aerodynamics of the compressor wheel. If you try to operate it at a non-efficient point, speed&flow, it beats the air up as it compresses it causing it to get hot.

The turbine side is the other limitation. It can cause problems with creating high backpressures, which is a high pressure in the exhaust manifold that acts to cancel out anymore boost you might add. The smaller the turbine and A/R ratio, the more restriction, but the faster spool up you get. A larger turbine and A/R allows more flow, but results in lower exhaust gas velocities and hence less momentum transfered to the turbine. It is a trade off like everything else in life.

The only thing that could be done to help is to get a turbo with a Variable area turbine nozzle that can regulates boost by constantly changing the turbine's flow characteristics. But good luck finding one that is affordable and will work on the 8.

The valve you are refering to is already used on all turbos, it is called a wastegate.

A few things to take into consderation about this video.What is the correction factor of the dyno or how come it is not SAE corrected? This can make a car with 100 horsepower at the wheels show 150+ horsepower at the wheels.On top of that the boost peaking out at 12.5 psi is ridiculous.We have never run more then 8.5 psi to make the power me made.Somone is going to blow a motor at 12.5 psi.They got a nice torque gain out of it but it should not have any impact on high rpm horsepower.The third thing is that with the boost dropping off to 5.5 psi there is no way this car is making 290 horsepower at the wheels! The turbo that is supplied witht eh greddy kit is to small to support this type of airflow, period. I am sure some of the other experts on this board would agree with this statement too.

Come run it on the un-biased(we do not own it it is not in our shop)dyno we use and I will pay to see it make this power.Finally you see hundreds of guys on here with Greddy kits that tune them and they dont make past 240 at the wheels running alot more boost.Now this car is making 50 more horsepower on top of that with some tuning and 5.5 psi of boost.And to add to it the A/F mixtures at the bottom of the chart looked really lean.I dont buy it.Take care.

I'm not an expert, but...

The corrections don't apply to FI engines

You are using a bigger turbo. more flow rate. same HP with less pressure.

Others have gotten it with the GReddy. One guy in Puerto Rico and another in Brazil who has 300HP to the wheels with it.


Prone to hyperbole, are we? I'd say the norm is 240 HP at the std. 5.5psi and no boost controller.

Not to bring this up again, but we haven't seen the results from your last car yet, have we? Did I miss it? You know what they say about stones and glass houses... :rolleyes:

how much could the SFR peak at hoursepower wise

Wow. And you turbo engines for a living?

Scary :(

I'm not an expert, but...The corrections don't apply to FI engines




Yes they do.You have been misinformed.






You are using a bigger turbo. more flow rate. same HP with less pressure.



Others have gotten it with the GReddy. One guy in Puerto Rico and another in Brazil who has 300HP to the wheels with it.



Ok, there is two guys in the entire world and did they make horsepower at 5.5 psi of boost? No. This is my problem with that claim!




Prone to hyperbole, are we? I'd say the norm is 240 HP at the std. 5.5psi and no boost controller.



I would disagree with you based on what others have posted here.



Not to bring this up again, but we haven't seen the results from your last car yet, have we? Did I miss it? You know what they say about stones and glass houses... :rolleyes:



280+ WHP out of our first car should give us a little credibility considering we were the first to make this type of power out of the Reneisis motor. Glass houses and stones? I have put together numerous thousand horsepower at the wheels cars so trust me I can make more power out of this stock rotary then anyone else I can think of. Our newset car is almost ready and then the world can see what we can do. Shoot I will even set-up a dyno day on an unbiased dyno here in San Diego and we will run our car against ANY greddy turboed RX-8.How is that for a glass house.

Unfortunately, you are basing your response off of a wrong answer. Remember, this particular person said he was not an expert and the fact is that I am. Call Dyno Dynamics, Mustang, Dynopak,etc....... and they all have some sort of correction factor that applies to all cars! This is why you see some turboed cars dyno charts with SAE correction on them instead of ACTUAL horsepower. Actual horsepower is not real because it doenst take into account, barometric,temperature or altitude compensation like the SAE correction does.

Shall I post some examples of turboed cars with SAE corrected dynocharts?

What is scary is when people read things(and beleive in them) on these boards that are written by others. who do not have the vast experience and knowledge that we do :rolleyes:

I'm not one of the members on here that are trying to discredit you, in fact I think you have done some great work, and its nice to have someone developing another system for our car. I'll also be the first to admit that I don't know much about turbos or tuning at all. I think the what most people on here want (and maybe the reason why they give you a hard time) is proven results. There has been a lot of talk about posting recent dyno charts on here for awhile, but nothing actually posted. Let me again say that I support your work, and thanks for dealing with all the people on this forum, but it would be nice to actually see the results of your hard work. Good luck, and keep up the great work! :)

Chrysler had a tricky way to deal with turbo lag. They called it a VNT Turbo (Garrett: http://turbosunleashed.com/shop/prod...33102f954061bc ) . I think it had some moveable nozzle to shoot the exhaust gas across the turbine blades at different angles. The problem was, the moveable nozzles would get gummed up from exhaust residue, then stop moving, which required the whole unit to be replaced to fix it.

I had the misfortune of having one of these cars. When it ran, it ran great (just about no turbo lag). When the turbo malfunctioned, it was time for a new turbo (ka-CHING!). I went thru 2 turbos in 40,000 miles, at which point I gave up & traded the car for a Mercedes E400.

I didn't base my response off what someone else said. I based it off the SAE themselves and the fact that I'm an engineer.

Dynojets correct using SAE J1349 a standard that is NOT designed for forced induction vehicles. It says so right in the standard. You will over-correct if you use SAE correction on an FI car. You can show me all the dynos you want, I've seen places dyno FI cars with SAE correction too, but that doesn't mean that's the technically correct thing to do.

You tell me, self-declared Mr. Expert, how a formula designed to correct for atmospheric pressure works when the engine is compensating for much of the loss of pressure on its' own by compressing the air before it goes into the engine. That's why FI cars do much better at higher altitudes than NA cars do. The Formula goes wacky with FI cars because it's correcting for a different level of atmospheric pressure than the engine is actually getting.

There are correction factors for FI cars that various people have come up with over the years that some places use, but there is no SAE standard for FI cars on a dynanometer. The only SAE standard for measing the output of FI cars is J1995 which is a measure of gross horsepower. That doesn't stop people from using SAE correction on FI cars though, which defeats the point because it's going to over-correct and under-correct more or less dependent on the altitude, which is the exact thing that SAE correction is supposed to prevent.

Before you get to bent out of shape.......... I am a self declared Mr. Expert in turbocharging cars that weren't designed to be turboed :D So cant we be friends again?

I agree that the correction for barometric pressure is redundant and even altitude to some extent but temperature is not (and I do understand that compression is taking place which raises the temperature). If we dyno on a cold 40F day vs. a hot 100F day then that correction evens the playing field, so to speak, since it uses 70F as a standard ;) For example.....if you dyno on a cold 40F day and make 220 horsepower and then it is corrected to lets say 200 horsepower. Now you do a run at 180 horsepower on a 100F day and it is corrected to 200hp. This correction allows you to make better, much more accurate comparisons.

If you guys want to see actual horsepower and that is all that matters in your eyes, then we will wait till winter hits to dyno our car so we make big numbers :p Just kidding, we are dynoing our car in 110F weather as we speak.

The turbo we use is capable of 500+ whp if you run enough boost :eek:

and how long are the apex seals expected at that level of boost?

how much boost would be needed to do 500 hp. how much boost psi wise can be safely run in the RX8
and also how do u deal with the apex seal issue

Personally I would think that will 500hp, your apex seals would exit your block shortly thereafter, at a great rate of speed, which most likely would destroy your turbo due to the MSP on teh renesis

I am trying not to make this get out of hand like the last thread, but I do have a few points here. I tried to be humble and point out that I am not an expert. But, SFR, you can't just come on here and bash one of your competitors with a bunch of exagerations and expect not to be called-out, especially being so brash about it.

Its your attitude about it that is the really bad part here. Especially when you have not been honest with us about the last car you worked on. Why won't you just tell us what happened? There were weeks with no results, and then some BS story about a broken 02 sensor. You said the car would have a new 02 sensor and would be on the dyno A MONTH AGO. Where the F is it? Come clean, man. This is why people are so hard on you: Attitude+deception.

You still haven't backed--up your claim that Mazsport was somehow fabricating their results. They have documented their results and shared them with the forum. And BTW, you have your facts wrong, it wasn't 5.5 psi that achieved the 290HP. Look again. They never claimed 290HP@5.5psi.

Also, while I am humble about my FI qualifications, you are plainly wrong about the SAE J1349 corrections applying to FI engines. Since the FI is going off relative pressure the corrections over compensate. Period. We can argue about the relative importance, but that depends on the boost as a percentage of ambient pressure. The fact is, SAE J1349 will overcompensate for FI. If you don't understand this, then you are not an expert by my standards.

Since this thread is about the differences between the GReddy kit and the SFR stuff, here is my take.

The GReddy kit is on the market. There are plenty of case studies available. The results with piggyback and quasi-standalone are available for everyone to review. There have been mixed results with the piggyback because of LTFT. If you are willing to reset this, then a good tune job can land you near 250 whp @ somewhere near 7psi. The turbo is small, but spools-up before 3k RPM. It will not provide over 300 whp. A standalone EMS will get you to this mark, however.

The SFR kit is largely undocumented. They achieved 280whp on one car. I have no doubt that this claim is valid. The second car that I know of that SFR worked-on was a forum member. The car went in for installation and the results were never shared. There seems to be a large degree of deception with regards to what happened to it. I seriously doubt that a broken WB02 is all that stood between that car and the dyno. The fact that the WB02 was to be replaced a month ago and we still have no results confirms this (for me at least). The SFR turbo is larger and will provide higher peak HP, at the expense of more boost lag. The SFR kit is more expensive.

but if it wasn't about the money which turbo would u guys pick???

Greddy or SFR?

lol at this point Greddy. or DIY for extreme results.

I would wait until you have more options then pick. Don't surrender to impatience, soon you have a better idea what kit you want because you would have more choices. But if I was to pick ssr or greddy kit, I pick greddy with the standalone ems option. But I seriously suggest you give this 6 more months when there are more viable options out there.

^ aye, rushing stuff on rotaries is normally a bad and expensive idea.

i would get the sfr if price was around 4500

At this point I would get the PTP Motorsports.

How come?