Okay so i've been searching these threads for about a month solid trying to decide if i want to go the FI route or stay NA. So everytime I read a thread that makes me think the greddy kits are worth the money and problems I read another one that says under no circumstances get the kit becuase it presents to many problems.

Basically i'm wanting yes or no's on whether FI is worth the problems for the gained HP. thanks for the help guys

 

FI is good, Greddy kit is bad (or atleast out of the box).

If you go Greddy you will also need...
Fuel pump upgrade(Mazsport)
ECU Upgrade (int-x/Ultimate)

Even then the kit does not push enough air to run to redline.


A better question would be "how much money do I want to spend"

6k = Greddy with upgrades
10k = Mazsport

 

i'm willing to spend the money to get it right

 

mazsport turbos capable of 400whp. i dont know what the highest dyno they have so far. look in their threads and you will find out everything

 

everythings in the process right now for mazsport right? theres like 2 superchargers out right now.

 

There aren't any SC's out yet. I had the Greddy, and trust me when I say it is more problematic than it was worth. Some people have good experiences, some people have had really bad experiences with it. If you are looking for some hp gain with simplicity then go nitrous. If you are willing to go through the expense & trouble of the turbo then I would highly recommend that you do the Mazsport and stay away from the Greddy.

 

See I really haven't heard or read much about people installing nitrous kits on 8's so i haven't really even considered it. is anyone here currently running a nitrous system?

 

look for threads by Charles R Hill for all your Nitrous questions. He is quite knowledgable on the subject.

 

there are quite a few of us juicers.....best bang for the buck

 

Hoping for the AFSC

 

Nitrous is the way to go for the dollar to hp ratio. Unless someone can come out with a individual throttle body setup with a programmed ecu and porting then nitrous would be your best bet

 

The candle that burns twice as bright only lasts half as long. Thats especially true with a rotary. Check out how many Turbo RX-7's that were left stock and never made it to 100,000 miles.

The Greddy is half baked. As someone else mentioned, it doesn't flow enough air to be usable throughout the ultra wide powerband.

At 10G's the Mazport is pretty cool, but for 10G's you could buy a used vette with 400HP.

The usual NA mods like flywheels intake & exhaust are novelties that will wear off after about 6 weeks.

Nitrous does some good stuff, but it doesn't last long.

Just not a lot of good solutions.

 

Actually you ask a fair question, but you can't get the answer unless people lay down 0-60 or 1/4 mile times and list all the mods they have.

Also, you have to see this as HP gained per dollar too.

You could spend $10,000 on FI, but is your return on investment versus cheaper mods worth it? Of course some of the NA mods can add up too or may not return a good HP gain? The thing about the NA mods would be the accumulation of many of them and what their effect would be on performance and faster times.


There is a lot that can be done on the NA side, and some mods may not be so obvious.

Examples:

. RB CAI and ram intake duct or other Mazdaspeed CAI
https://www.rx8club.com/showthread.p...old+air+intake
https://www.rx8club.com/showthread.p...9&page=1&pp=15

. Agency pulley
https://www.rx8club.com/showthread.p...=agency+pulley

. flywheel (manual only)
https://www.rx8club.com/showthread.p...light=flywheel

. Breather mod
https://www.rx8club.com/showthread.p...light=breather
https://www.rx8club.com/showthread.p...reather+filter

. Throttle body bypass mod
https://www.rx8club.com/showthread.p...light=breather

. Mazsport fan mod ( https://www.rx8club.com/showthread.p...t=mazsport+fan )

. Re-Amemiya or Racing Beat ECU flash. or Interceptor-X to modify ECU (can get expensive)
Note- can find some more power or allow you to push the rev limit to get a little more.

. ATF cooler and AT fluid (Redline or Royal Purple) (Automatic only)
Note 1- useful if ECU flashed or modified by Interceptor-X. Allows auto tranny to withstand higher revs.
Note 2- Should consider placing 2nd oil cooler to if 4AT. Have ATF cooler mounted in front and NOT where 2nd oil cooler goes.

https://www.rx8club.com/showthread.p...&highlight=ATF
https://www.rx8club.com/showthread.p...&highlight=ATF
https://www.rx8club.com/series-i-specific-performance-mods-97/atf-2nd-oil-cooler-what-kind-u-using-104596/

. Synthetic oil and HP increases?

Note- Royal Purple, Amsoil, etc claim HP increases if used.

https://www.rx8club.com/showthread.p...=synthetic+oil

. Air filter and power increase?

https://www.rx8club.com/showthread.p...hlight=r-magic
Note- I did see about a 3 HP increase, believe it or not.

. Better gas or higher octane gas = performance increase?

. Exhaust
Note- Can get expensive, have to think about if you are going FI later, people argue you may lose power for some exhausts and gain on some others...
https://www.rx8club.com/showthread.p...light=exhausts

. Nitrous
Note- This is really one of those plus vs minus that you have to think about, but there is no arguing that a nitrous kit could lay the wood to a FI kit in the 0-60 or 1/4 mile depending on the setup. Of course you can NOT use nitrous forever or continuously...

https://www.rx8club.com/showthread.p...hlight=nitrous

 

recently I've been dabbling over the idea of "what if" I saved my money for that Greddy kit instead of just attempting too mess with my rotary being NA....

For starters I find changing our engines from a 6 port too a 4 port a step back. Next comes the cost of somewhere around 3,500 for a (average) 30% increase in power... Within the past couple of weeks I've dropped some 1,600 for an intake,under drive pulley, and flywheel... At half the price I'm almost expecting half the power increase too that of an 8 with the Greddy turbo.

Ofcourse it's all speculation about how much power is actually gained, but once I get these things done I'll see how quick it will take for me to become bored with my setup... I guess the next cheapest thing is nitrous, but that stuff kind of scares me...

 

The thing about NA mods, besides being cheaper or that you can pay for them in increments (as oppose to a huge sum to a tuner or for a kit), is they will often be more reliable.

A turbo kit opens a whole world of possible install and maintenance issues that a driver might not want to deal with. With an intake, pulley, breather mod, flywheel, etc... you do it or your local mechanic does it and your often done or don't have to worry too much about them.

Also, a HP claim is meaningless if its not backed up by improved 0-60 or 1/4 mile times. Somebody can say they got an extra 100 HP over you, but what does that translate to in short distance and straight line performance? What was the point of the FI kit if it does not show up in the 0-60?

A lot depends on how the power is delivered. Where does the power show up at? At 2,000 RPMs and as soon as your foot hits the gas or much later. As most people know, the RX-8 needs it down low. The RX-8 will deliver if you have it revving at 7,000 plus RPMs.

Does the kit make a 3 seconds difference or simply a 1 second difference? 3 seconds could be huge and something you really feel. 1 or 1/2 a second could be hardly noticed. So not just the HP, but what is the amount of money spent per second decrease in times?

 

so it's like 6 NA'ers to only 1 FI. But i'm really liking the idea of installing nitrous as an alternative to FI. any other pro FI people out care to give there .02 cents?

 

A naturally aspirated car will always cost more to build and have the least amount of power per dollar spent. It's not saying don't do it. It's just true.

Forced induction need not cost $10K. A Greddy kit can be had for much less. The key to it is to fix some things with it that Greddy did half *** such as the ecu setup and tuning. Mazdamaniac can help you with this. It's a decent gain for the money and you've always got it.

For most power right now, nitrous is the way to go. Obviously it's not permanent but many like the aspect of having the power only when you need it. It is a mod that keeps costing money the more you use it. For good nitrous info contact Charles Hill.

My personal opinion is that if you want some extra power (up to 300 or so at the crank) but not 400+, go with a Greddy turbo kit and fix the issues with it.

 

I've had the Greddy kit for almost two years now. I personally like it. It makes a huge difference in how fast the car is and how much fun it is to drive. I'm pushing just under 300whp with the Greddy kit, exhaust, and boost controller. Don't expect it to make the car into a 12second car though. It does make it into a "respectable" (no flaming please, just my opinion) sports car that can compete with STI's, evo's, 350z, and Mustangs. In my opinion your wasting money with NA mods. You can buy everything that's available and you'll be lucky to get a 20whp gain. Not worth it, again imo.

Its true that the Greddy turbo does start to run out of power up top, but that's just what it's designed for. It gives a strong midrange boost which is preferable if you mainly drive around town and don't plan to race it often. It gives a big fun factor when you have a huge torque gain from 3000-7000rpms.

The reason we aren't seeing vastly improved 1/4 mile times is that when racing most people are spending their time above 7k rpms, where the torque is falling off. It doesn't really speak to the improve acceleration you feel when driving. If you go with a bigger turbo, ya you will probably hold your torque up longer, but at the expense of that fun midrange torque. Just the way it works. So decide if you want impressive 1/4 mile times, or more of a fun factor.

You can pick up a used Greddy kit for $2k. Get an Intx, a tune and some gauges and you'll be setup for just a little over $4k. Keep in mind most of these people speaking against FI, don't really have any experience with it. Not good people to be taking advise from. It's like getting advise on girls from a virgin.

There is the possibility that you will blow your motor. Be prepared for this. If you can't afford to replace it, then I wouldn't recommend going FI or NOS. For some reason, I think people are under the impression that NOS is safer, but its not. Its still a risky game. But, a reman'd motor is only a little over $3k. While that is a lot of money, it shouldn't be the end of the world or else you shouldn't have been playing the game to start with.

 

Not a fair comparison.

The greddy kit runs about 3k. Replacement hoses are about $100. That's it. Add $1400 if you want to use the int-x instead of the EMU, but subtract $400-500 from that price because you can sell the EMU off and recoup.

You're right that a finished greddy kit will likely cost around 6k. To keep things simple, let's assume 3.5k for the kit, 1k for install, 2k for gauges, boost controller, and a bit of tuning.


The mazsport kit while more complete, costs more - and I don't mean just on initial costs.

Lets say you get the $8,000 type 1 kit (lowest priced). Add in the same 2k for gauges and tuning that we did for the greddy kit, and 1k for install of the turbo kit itself. You still need to add in 4 hours for fuel pump install, 3 hours for fuel injector install. Motor mount install time, etc.


As I said, it's not an apples to apples comparison, the mazsport kit comes with things the greddy doesn't, but it's going to cost more to install than the greddy. So by the time you're done, you're looking at around 12k - 14k (depending on which kit you get) vs 6k for the greddy.

If you're doing the install yourself, then prices will come down on both sides, but considering the $6k figure you quoted for the greddy, that isn't what you meant.


I think it's a disservice to others to downplay the cost of any mod.

 

I know that I'm stealing this thread for asking this question... I've allready searched and can't find any information, making me wonder if it is a stupid question. Which only further makes me doubt about starting a thread over this topic...

But anyway, would having bigger fuel injectors (or getting the fuel pump upgrade from Mazsport) on a NA engine be able to increase power at all?

 

No, your car already runs too rich. you get more power out of it NA by leaning the air fuel ratio, not dumping more on.

 

Good advise. I know of some people that end up losing their cars because they mod it, then it breaks and they can't afford to fix it. All this while they're still making payments on it.

 

No the ECU just tells the fuel system to spray for a certain amount of time, no matter how large the injectors are. Unless your car is throwing in more air (i.e.forced induction), dumping in more fuel will just make the air/fuel ratio too rich and cause your engine to throw a CEL, and compromise the driveability of your car.

If I had t to do all over again. I would have just built up my car what i could do NA (Intake, exhaust, hi-flow cat, ECU flash, pully) and then if I had wanted more hp just done the ZEX wet nitrous system with 55 hp shot like the one Charles R. Hill had/recommends. It would have been a lot less problematic.

I went in thinking that the turbo kit would give me better midrange (it did), but be relatively easy to put on, with a bit of tuning and we would have been good. A "bolt on" kit with some tuning. It turned out much more problematic then that. The new turbo kits have been improved (new add on kit is included) with better FMU, though the EManage Ultimate is still not that great. Just lost my faith in Greddy with their missing parts, and **** poor customer service, and lack of technical support for their kit.

If I had to do it all over again, the nitrous kit, even though it would need tuning it (though less) would have been far less problematic. At least from the experiences I have seen here on this board from the people who had the Zex kit, and is less technically intensive.

Just a perspective from someone who is NA now, that was FI'ed. When you blow your engine, it's not just the cost of the engine, it's getting stuck out there when your car is toast, towing it into your dealership (if you use roadside assistance), or towing it to your mechanic who will do the engine swap, getting rides to/from all these places, not to mention god forbid if you are far from home when you blow the engine. Just some other things to think about before you FI your engine. This can be turbo, or nitrous (just, easier, less technical install).

 

No turbo. My .02

 

Best way to go about it is to find a few local guys with FI - get a ride with them, chat and see how installs went, who they had do the work, what it cost, etc.