Correct me if I'm wrong about the gains these NA mods provide.
 

So I did some searching:
From what I gather, best mods (for response and power)
EMS, Flywheel, pulleys (maybe not so because the rx8 has electric power steering)

Then these make no power (or very little difference)
Intake, Race Pipe, Exhaust

Am I right or am I wrong? I'm asking mostly because some companies claim big hp increases with their intakes, race pipes and exhaust.

Thanks

you are right. you will get minimal gains if any from those upgrades. A lot of money for nothing.

So best to stick with flywheel/clutch? and maybe pulley? and then tuning (whenever cobb comes out with the access port)

Flywheel is good - EMS does some - pulley does a little .
No - one thing will make you that fast . Put them all together and you are noticably quicker than stock - just don't try taking on any EVOs .

But are intakes, midpipes and exhausts worth getting even tuned? Do they provide any noticeable difference even when tuned?

Most likely I'd save up for boost, as I was a boost junkie with my former supercharged sentra...but that's major $$$ I don't have to spend.

If you haven't already looked it up - interceptor-x works for some people - it throws a CEL but evidently nothing major if installed and tuned properly. Most people with it installed have noticed a definate power increase. Then possibly look into a high flow cat or removing the cat completely. CAI if you wanna be fancy but over all with the int-x, it should max out some better #'s...

well if you plan on boosting in the future a good race pipe and cat back never hurt, make your own list on what things you want done and the results you want to exepect. you have the right idea. good luck

the only reason intake/exhaust don't work with the stock ECU tune is because the 6000 + RPM range is all ready too rich. I'm currently running with out a catalytic converter, and would say with all the other supporting mods my 8 definitely has a noticeable pull no matter what RPM range another stock Rx 8 meets me at.

Now that I'm stressing the need for Racing Beat's flash, for those who just want too "daily drive" there 8's, and not for those considering any forced induction. My list goes in this order of "noticeable gains"

1.) Tune (keep the coolant fans on, lean higher RPM's, if you tune with a mid pipe then richen the mid-range, raise the rev limiter, and your set)
2.) Flywheel (find the one's with the least rotational mass, no reason too get all nancy style in this category)
3.) Exhaust (depending on whether you decide too go the mid pipe route, the 3,000-5,000 power change put the biggest smile on my face, if you do decide you want too keep your cat then after the tune getting one of those super cat's might yield some gain other than that choose for sound/personality in the tone of each exhaust)
4.) At this point, I couldn't tell you if the Agency Power's under drive pulley would be better or worse than an intake. On a hot day I hate my intake, on a cold one I love it. AP's under drive pulley is half the price of any intake these days, so I'd be leaning towards the under drive pulley just for cost's sake. Also you wouldn't have too worry "too much" about the A/C being hot at idle, yes the A/C will be suck below 2,000 RPM's but if both coolant fans are on, then you won't die

I installed my straight-line oriented parts pretty much in the opposite order. Which was a HUGE mistake, in the sense that the whole time I had a super cat. Within weeks of installing my intake/flywheel/UD pulley all at once, my catalytic converter melted! It decided too shove itself into the Y-pipe, leading me too spend 200 bucks just find it, then too get it out on several different locations it practically melted itself into. After that experience I figured why not void out every wretched post every incurred onto this beautiful car about any catalytic converters, and since then have sworn too Racing Beat's convenient flash.

Once you tune, you will be able too "feel" every other supporting modification better.

Hmm I really like how the stock exhaust is quiet...I dislike loud exhausts with a passion.

I saw some vids of the turbo xs one, and it needs more resonators so loud =/

Would a midpipe to more than an exhaust?

I was thinking:
Tune
Flywheel
Midpipe

Unless if the exhaust helps a lot, but I don't have any way of getting it retuned without spending $$$$$$$ to buy a piggy back of some sort.

the only reason you would get an exhaust and midpipe would be for sound and looks.........no other reason(unless ur turboed)

as for intakes...........just go get a turbo, theres not really a reason

if you plan on going with the Racing Beat tune, than I wouldn't even consider a mid-pipe. When you do "race", you spend your time in the 6,000 RPM and higher range... The mid-range torque difference I speak about is pretty much just for daily driving, but sometimes it's not worth dying for... Literally, dying for...

Intakes do make power but like all NA mods it's up high. What some people get fixated on is they think because it gives an "average" of 2 hp across the rev band that is nothing, but if you look at the dynoes it's nothing in the low end, a few hp in the midrange, and about 6-8 on the upper rev range. But that is true of all NA mods. From exhausts, to midpipe/hiflow cats, etc. It's the nature of our engine. If anything the pulley shows only minimal gains but since it's such a cheap mod you might as well do it.

Even if you do the intake, pulley, hi-flow cat, reflash & exhaust you are looking at most +20 hp & most of that is on the high end. There is no magic bullet. If you want low end power you have to go FI, but that will incorporate a lot of time & $$$.

Fanman: Never stated anything about low end power...never complained about it...even though my last car made more to the wheels stock for torque at 4000 rpm than the RX8 makes at peak torque at the crank. Then when I added boost...well I've never seen an RX8 make 240whp and 220lb-ft torque all under 6000 rpm on 4.5 psi :) But I'm not complaining about the RX8's low end torque, I don't have any problems with it.

I wouldn't do hi-flow cat...no point. No emissions laws here, so I'd just throw on a midpipe.

Keef: Racing beat to my knowledge offers two flashes, one 'street' designed to work with a cat, and one 'race' designed to work without a cat as it runs leaner which means hotter temps which means fried cat. No thanks.

tajabaho1: Midpipes to my reading does much more than just sound, it gets rid of the cat, and allows you to use the RB race flash. I'm trying to find out how large the stock piping is to the stock muffler and out.

Boost I know will be good for low end torque but:
1) Cost is $$$ and for boost you basically need clutch/flywheel/full exhaust anyways...so doing the RB flash before hand until saving up for boost is a small price to pay.
2) I like superchargers more than turbos. There are two, pettit racing, and DNA motorsports. Both cost $$$. DNA motorsports appealing to me MUCH more because I am familar with prochargers (used on my last car) and they are much more quiet compared to a roots style (meowing cat sound)

Midpipe might cause you to trip a CEL light, and a lot of people will tell you get a stinky tailpipe. Be careful. You are looking at about 8-10 hp with the midpipe & exhaust, not to mention you said you don't like it too loud, it will be quite a bit louder without the cat & resonator.

stock piping is 2.5"

I have seen centrifugal SC's a long time ago, but to date haven't seen one that has been operational or functional. Pettit is supposed to be real close to completion & Axialflow is somewhere close. Saw both systems at Sevenstock.

^^The Pettit Supercharger is not a Roots type it's a Lyshom type. Much more efficient than a Roots type.

Check out Mysql101's thread on turbo and supercharger compilation for performance comparisons.

www.racingbeat.com has some good info. on the effect of their flash with and without their intake and exhaust installed.

Fanman: My last car had no cat...it made boost...it stunk...shot flames...I didn't care :) CEL light is easy to take care of with a drilled out spark plug fouler, at least it works on most cars. If the stock piping is 2.5" then how do *most* catback exhausts (with 2.5" piping) offer any power increase? The only restriction I can really see would be the cat...and if I just made new piping I'd have a resonator put in :) I'm not sure at all how a midpipe and exhaust can net 10whp on it's own...when I've seen dynos using intake/header/tune/full 3" exhaust/pullies/flywheel/tune make only 18-20whp more.

The Axialflow is something I'm really interested as it should be slient, less fussy to install, give enough hp, and be tuned by cobb.

shaunv74: My bad...The main reason I don't like it, is because it overpowers the stock rotary sound, the sound I'm addicted to.

Charles R. Hill: I'm not 100% sure what you mean, I'm trying to discover the truth. Post examples from this post please.

This board REALLY needs a sticky on proven NA build ups.. Anyone with a proven method of what they did to get 15whp or more could post all the parts they bolted on and any other mods that assisted (tuning) with dyno sheets.

Exactly I've only been able to find a small amount of dyno sheets, that show minimal gains.

But then every single manufacturer has 20whp off a catback...

Because the issue is, to go FI, you must take some basic NA steps. Things like a stronger lighter flywheel, exhaust, etc should already be done by the time you go FI.

I would go FI if I new I had the money for an engine rebuild down the road... The only reason forced induction had me scared is because there's more air, more fuel, more heat. And heat from what I understand is what takes a toll on a rotary engine.

In my perspective, I would rather just use a 50 shot of nitrous sparingly... 50+20=70 more horse power that I can use through 5,000 RPM's and higher. Versus a Greddy 8 that cuts of at 7,000 RPM's

I went with the Corksport catback because of the reduction in weight. The OEM muffler is heavy. There are other catback's that will help you loose weight. Reducing weight is like gaining HP.

Keef: If you take precautions FI shouldn't scare you. Tuning, cooling, etc should all be addressed before hand. My last car was a Nissan Sentra SER with a QR25, if you think the RX8's rotary has problems, the QR25 IMO is one of the least reliable engines ever built...precat was consumed blowing up the engine, random oil consumption (when it shouldn't), injecting butter fly screws and valves blowing up the engine. I took care of all of those, strapped on a procharger @ 4.5 lb, made 100whp and ~60lb/ft over stock...I was going to push it to 9.5lb until it was written off.

Charles: Okay that's how *I* would do it, because I think it's just the best way to do it. Well maybe not full exhaust, but at least a mid pipe as that seems to be the most restrictive part of the exhaust system. Although I'm still unsure how a full 3" exhaust can contribute 10whp...when using intake, exhaust, flywheel, midpipe, and tune nets like 20whp.

alnielsen: Although weight reduction will probably make up for any lack of hp gained by just an exhaust. But it will not come before my primary goal of making the car look and sound stock. Back to my supercharged sentra (which I miss a lot) From the outside, looked completely stock except for slightly lowered, the exhaust was 2.5" mandrel bent from the header back, was made to look, hang, and sound stock (it was BARELY louder than stock after I got the 2nd resonator in). When the car was on, you could hear a slight gear noise coming from the procharger, it was only until I whomped on it went into boost you could hear the suction of the procharger and my BOV.

If I get a full exhaust (which if I go FI, I would want one that basically looks, hangs and sounds stock, which might involve having nothing but resonators and a huge chambered end mufflers with a custom plate cover to make them look like a stock muffler.

Dyno numbers for this car are funky. SOme have speculated it is a cat overheat mode, or the car gets weird when the front wheels aren't moving. There's a bunch of speculation as to why the RX-8 dyno's weird, but we know it does. People have done three pulls on the same day back-to-back-to-back, and ranged from 175-192rwhp. Obviously, dyno's are going to be inconsistent.

If you want a stock sounding and looking exhaust, I would suggest the Mazdaspeed V2.

You CAN gain some horsepower NA. It's just these funky dynos that have people saying you won't, and then people kept repeating it and now everyone believes it. There is power to be made in NA trim.

It's true a midpipe will give you a lot more power than a catback by itself. The main exhaust constriction is internally in the engine- you will need to do porting for that.

Intakes are mostly noise makers, but some will net you a few ponies. It varies car to car. But they're expensive few little pay-off. I think the stock airbox with a high flow filter (like K&N) is a good setup, and only $55 or less as well.

Mountains of research and sleepless nights

Charles and Rotarygod know exactly where the exhaust restriction is...

If you're considering FI you'll need to improve your cooling system and airflow through the engine compartment.

Like this: https://www.rx8club.com/showpost.php...3&postcount=13