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LiveWire
07-10-2011, 04:43 PM
Alright so I have a question. What are the performance differences between the 04 -06 RX8s and the R3? (Excluding basic driving differences and cosmetics) would I be correct in sayign that the R3 just has upgraded exhaust, intake, and suspension?

Secondly, I was wondering a lot about porting. Basically here is a rundown of questions. Feel free to add more answers in because though I know the basic concept (the diff b/t street, race, and bridge port) I dont really know to much more. So here goes:
1) How much would a street/race port cost?
2) I believe street ports are street legal and race, bridge ports are not. Is that correct?
3) Where would I have to go to get this done? Would a tuner who knows a lot about rotories be able to do this, or would I have to go to rotory engine rebuilder?
4) I understand that porting makes the car louder, less fuel efficient, and more powerful. Would I be correct in saying that the increased flow or air would create less wear on the apex seals? (less pressure on the third stroke?)

Thanks for your time guys

reddozen
07-10-2011, 09:37 PM
Alright so I have a question. What are the performance differences between the 04 -06 RX8s and the R3? (Excluding basic driving differences and cosmetics) would I be correct in sayign that the R3 just has upgraded exhaust, intake, and suspension?

Secondly, I was wondering a lot about porting. Basically here is a rundown of questions. Feel free to add more answers in because though I know the basic concept (the diff b/t street, race, and bridge port) I dont really know to much more. So here goes:
1) How much would a street/race port cost?
2) I believe street ports are street legal and race, bridge ports are not. Is that correct?
3) Where would I have to go to get this done? Would a tuner who knows a lot about rotories be able to do this, or would I have to go to rotory engine rebuilder?
4) I understand that porting makes the car louder, less fuel efficient, and more powerful. Would I be correct in saying that the increased flow or air would create less wear on the apex seals? (less pressure on the third stroke?)

Thanks for your time guys

I think the only real difference in the R3 is suspension, wheels, and seats.
09' and up cars have an extra oil injector per rotor and a few other small changes for reliability.

Where are you from? that will make a big difference with porting / costs / etc.

1) 200~600 USD depending on what you want done.

2) nothing is "illegal" as long as it passes any emissions requirements that are required in your area. They don't know what a "bridge port" is.

3) This is a kind of ill-informed question. You need to do a bit more research. generally builders preform porting, but not all porting is equal.

4a) louder... somewhat, but this is mostly dependent on exhaust.
4b) less fuel efficient... tuning. Typically less efficient, but I get close to the same mileage with a bridge port on a renesis.
4c) more powerful... depends on the quality of the work and tuning.
4d) less wear... seriously!? more power = more wear in ALL cases.

I think you need to do a lot more research before you ask any more of these kind of questions, and I wouldn't recommend getting any port work done till you understand better what it will entail. I recommend you visit the RX8club.com forums and do a little research. Also, understand that you will not get large power gains from a Renesis from port work. We're talking no more than 5~30 HP depending on the motor and the setup. Don't expect to get to more than 220 WHP without a turbo or supercharger, or a LOT of money.

If you want something easy to tune, stick to pre 09' cars since you can use an access port to reflash the ECU. Other wise, you will have to get a standalone computer.

j9fd3s
07-11-2011, 12:28 PM
between the 04-08 and the 09+ cars the 09+ have a TON of small upgrades. the suspension geometry is all different, interior is revised etc etc. basically they are very similar but do not share that many pieces.
although on the other hand, most of the changes are small ones

1. the port only costs 400-600, but the engine needs to be removed from the car, and disassembled, which is probably another $1000 in labor if you're not doing it yourself.

2. a bridgeport will never pass smog, so if you need to smog the car, its not going to be legal.

3. since the engine needs to come apart, probably an engine builder

4. noise; it might be a little louder, with the old engines, you MUST have a freeflow exhaust, which tends to be loud. on the Rx8 engine i don't think its as big of a need, so it should be easier to keep it quieter.

mileage; im my experience with the older engines, a street port actually HELPS mileage. YMMV though.

power; dunno, depends on the size of the stock port vs the new one. the stock ports are already good sized, and they didn't leave you a lot of room for more, so i wouldn't expect a huge jump from a street port.

apex seals; flow of air? no. more power = more heat = faster wear.

LiveWire
07-11-2011, 12:36 PM
Well thanks for the info and thank you for bearing with me first of all. Believe it or not, research on this is not the easiest thing to accomplish haha. This is the third forum I have been refered to while doing all my research, but again, thank you for your partience here. I am from Hinckley OH, basically 30-45 min south of Cleveland. From what I hear, our emission are one of the worse city's b/c we are near big populations of people (we really aren't but whatever). So things like catalyc converters are required.

And yes, dont worry, I understand that I cant get abouve 250 hp at the crack easily without FI. Ive been down this expensive plan time and time again. One thing Ive learned though is that if I do (probably turbocharge) an Rx8, I should go to Turblown. I was planning on a pro tune anyway, but I will probably get an 04-06 Rx8 regardless, since I will probably redo suspension and wheels anyway.

Thank you for the clarifications, estimates, etc. It is much appreciated.

reddozen
07-11-2011, 01:53 PM
j9fd3s, Smog depends on how they test it. If it's all OBD2 like it is here, plug in the access port, disable the check engine codes and it'll pass every time. Some places still require sniffing, but here, they wont do it even if you beg.

With tuning and a good high flow cat, I think you could pass a sniff test even with a bridge port in a renesis.

Here's a clip of my car after we got it running... It's not all that loud even with 3" straight exhaust. It rarely throws the "lean burn" code, but I'll disable that once we're done tuning it, so think it would still be possible to pass a sniff test.

www.youtube.com/watch?v=C-WkRBKpqIE

j9fd3s
07-12-2011, 12:55 PM
wow that's pretty cool, i'm in california and a bridge would never pass here

LiveWire
07-14-2011, 09:36 AM
That heartbeat to your car sounds really nice reddozen. Thats honestly one of the nicest sounding idles I've heard out of an 8, and that wasn't even in person. I was definately going to get an access port down the road when I finally go FI, but if it gets me to pass e-checks Ill suck it up and buy it.

I would not be doing the engine pull myself, as I have no lift and never have done one b4 so I would have to go to a rebuilder. In such a case, what all should I be looking to get to get a good 100k+ miles out of an engine (later with FI). I was thinking heavier rotors, better seals, and a port.

reddozen
07-14-2011, 03:41 PM
I would not be doing the engine pull myself, as I have no lift and never have done one b4 so I would have to go to a rebuilder. In such a case, what all should I be looking to get to get a good 100k+ miles out of an engine (later with FI). I was thinking heavier rotors, better seals, and a port.

100k miles = regular maintenance, premix, etc
cant get heavier rotors, nor would you want them.
"better seals" is kinda relative... you could get ceramic seals, but you'll have low compression at low RPM.

I would highly recommend having your rotors and eshaft balanced, and keeping your RPMs under 8500 RPM. There's really no power to be had over 8k RPMs.

LiveWire
07-14-2011, 09:54 PM
I heard the rx8 13bs dont take well to forced induction because of high compression ratio and lightweight rotors, so my solution was the superdense (I believe thats what they are called?) rotors and a tune. Is this incorrect?

I was thinking ceramic to hold up better at high rpm? (another assuming info is correct) My plan was to basically prep the stock rx8 13b for FI down the road and this FI would be tuned for high rpm boost, since the rotories do well in high rpms anyway. haha I have accepted the plague of low torque at low rpms, it does not bother me too much. Anyway as for the 100k+ miles, I just dont want to get a used car and have the engine "fall apart" (I do understand its not literally falling apart rather just losing its compression ratio) after I get to 100k because the previous owner was a nincompoop and didnt know how to take care of a rotory car. So people are lucky and get good engines, but I hear of a lot who dont, so I dont want to prep the car just to need a new engine soon anyway. So I guess my question is will new seals (+ a tune) solve most compression ratio issues?

j9fd3s
07-15-2011, 02:08 PM
if you go and look at the japanese tuner websites you'll see that an engine rebuild to closer tolerances is stage I for the Rx8. the factory engines are either a little sloppy with seal clearances, or worn; take your pick

stage II is the ECU tune, with an intake/exhaust.

stage III is the turbo/supercharger, depending on the shop.

due to the "cut off" seal, which is needed for the side exhaust ports, the Rx8 rotors are the only ones that will work in the Rx8 engine. with FI the tune and selection of parts is important.

LiveWire
07-16-2011, 10:55 PM
Thanks j9fd3s, very useful info and right to the point. I heard a lot of good things about turblown turbos, such as that they can get a stock rx8 13b up to 400+ hp with relatively lower boost levels. My goal is probably something modest, around 330 hp and 270 ft lbs of torque without extra systems like meth injection. Is this do-able keeping reliability intact for a dd vehicle?

LiveWire
07-16-2011, 10:57 PM
I also appologize if my choppiness and random questions seem like freelancing. I just want to have plenty of research done before I go actually do anything. If there is one thing I've learned about these cars, its that you have to know whats going on. Regardless, it has always been my dream to own a rotory powered car. So thanks for your patience guys!

Sephitrask
07-18-2011, 06:17 PM
Thanks j9fd3s, very useful info and right to the point. I heard a lot of good things about turblown turbos, such as that they can get a stock rx8 13b up to 400+ hp with relatively lower boost levels. My goal is probably something modest, around 330 hp and 270 ft lbs of torque without extra systems like meth injection. Is this do-able keeping reliability intact for a dd vehicle?

So, after re reading this thread, I am wondering, have you actually bought an rx8 yet?

On turbo'ing the renesis, 400+ is a very lofty goal. I have seen people extensively mod their car, only to obtain right at 300 hp. There are some new kits out claiming 400+, but I am very skeptical of it, especially on a stock motor. The stock motor just doesn't handle boost very well. The biggest issue, aside from poor build quality, as stated above, is the side port exhaust. On your previous rotary engines, the exhaust was very free flowing, with the exhaust simply being pushed out the rotor housing. Hell, if you blow an apex seal on one of those it will eventually get tossed out too. Not so with the renesis. For the exhaust, it has to make a 90 degree turn into the side iron, then another 90 out to the exhaust manifold. Because of that, you have ALOT more heat buildup in the engine. The renesis exhaust gas temps are 2 to 4 hundred degrees cooler than the rew; thats because the heat is sitting in the side irons instead of flowing freely out. oh, and if you loose an apex seal, its just gonna get bounced around inside of the housing, destroying everything in its path.

Now dont get me wrong, I LOVE the rx8. I have one, and NEVER regret buying it. Just keep in mind that if you are looking for 400+ Hp out of it, its a long hard road ahead for you, that may not have a happy ending at the end. Most people I am aware of gave up on the renesis and went RE, REW, or 20b. I know a guy named Steve in Melbourne that has a REW in his 8, and it was a relatively straight forward swap, all things considered. It WAS expensive though.

Chibana
07-19-2011, 12:45 PM
I would soooo love to have a 20b in my RX-8, but there are two things stopping me: (1) money; and (2) I'm not the least bit mechanically inclined. I know I could get someone to do the 20b swap for me, but I have to think it's probably not a good thing to do if I have to haul the car 80 miles away to have it fixed if something breaks. A 20b swap really seems like the kind of thing to do only if you can at least maintain it yourself. Money might not be such a big issue after my 09 RX-8 is paid off.

Max777
07-19-2011, 07:15 PM
I would soooo love to have a 20b in my RX-8, but there are two things stopping me: (1) money; and (2) I'm not the least bit mechanically inclined.


See, this is your problem right here. You WANT to have something fast, yet you dont have the skill to make it happen.

My advice is: learn how to work on your car first, change the oil, fix the brakes, do a 60K serivce. Get comfortable holding a wrench. THEN come back and start building your car for power.

also, dont just go for a number, like 400hp right off the bat. Learn to drive the car at the stock power, take it to autocross, and maybe some track days, try to get the most out of the entire car stock before you go and make changes to it.

reddozen
07-19-2011, 08:05 PM
See, this is your problem right here. You WANT to have something fast, yet you dont have the skill to make it happen.

My advice is: learn how to work on your car first, change the oil, fix the brakes, do a 60K serivce. Get comfortable holding a wrench. THEN come back and start building your car for power.

also, dont just go for a number, like 400hp right off the bat. Learn to drive the car at the stock power, take it to autocross, and maybe some track days, try to get the most out of the entire car stock before you go and make changes to it.

you realize that The person you quoted is not the same person that started the thread right...

LiveWire
07-20-2011, 10:14 AM
Yeah Im the guy who started the thread. Also reddozen, you are correct in your assumption, I do not own any car of my own yet. Right now, I drive my father's 2009 sonata, though I do help my brothers when they work with their cars. My older brother has an Evo X and my oldest has an 06 STI, so I am no stranger to the wrench haha. I dont really ever plan to get up to 400hp without a swapped engine to clarify, Im basically feeling out how far I could go safely and reliably. Also im in year 4 of 6 with my research on the rx8, I heard no research is enough with this car, so nothing is happening really soon, this is more/less all preparation and planning and info searching. I think I have another thread up explaining this but what the hell. Just finished freshman year at Miami in Oxford, major in electrical engineering. Planning on getting the car summer of Junior year. I have basically wanted an rx8 since I could first drive, and after A LOT of thought I still know that a rotory engine is the one for me. For better or for worse, I will get a rotory car, be it rx7, rx8, or rx9 (if it even comes out).

Chibana
07-20-2011, 04:01 PM
you realize that The person you quoted is not the same person that started the thread right...

Thanks, reddozen.

I *recognize* that I shouldn't go that route. That was the point of my post. As much as I would love a 20b, it's probably a really bad idea for me.

j9fd3s
07-22-2011, 08:42 PM
Also im in year 4 of 6 with my research on the rx8, I heard no research is enough with this car

i drove one in very late 2003, and it took like 3 blocks to realize it was a really awesome car.

the DD at the time was either a 3 rotor FC, or a modded GSL-SE. the rx8 IS fun in the same way that the 1st gen is, and its faster, handles better, rides better, its quieter, has a better radio.

no research needed!

my second drive was on a roadrace track, the Rx8 is AWESOME there, you can do STUPID things behind the wheel, and the car won't bite you. the trans gearing is just about perfect. it doesn't FEEL very fast, but it'll run right with an IT (improved touring) FC.

again no research needed!

you want something faster than an STI in a straight line?

research needed!

LiveWire
07-24-2011, 06:40 PM
Oh don't worry, I have given up on beating my brothers' cars in 0-60 times a long time ago. With the awd, 2 liters, and turbos they beat vettes off the line to 60, let alone a car with an engine almost half the size. Nevertheless, I heard good things about cornering with this car.

j9fd3s
07-25-2011, 11:14 AM
Oh don't worry, I have given up on beating my brothers' cars in 0-60 times a long time ago. With the awd, 2 liters, and turbos they beat vettes off the line to 60, let alone a car with an engine almost half the size. Nevertheless, I heard good things about cornering with this car.

yes the chassis is just amazing. somehow they ended up with something that rides nice, its easy to drive fast, and won't bite you. lap times, if you're into that, are surprisingly good.

Sephitrask
07-26-2011, 07:56 AM
yes the chassis is just amazing. somehow they ended up with something that rides nice, its easy to drive fast, and won't bite you. lap times, if you're into that, are surprisingly good.

Yeah, the car is great at being easy to drive fast. it is just so forgiving! I actually dropped two wheels off the side of the dragon due to ALOT of gravel on the road, and was able to recover as if nothing happened. Would not have been able to do that in the other cars I used to drive. My friend Adam, who is a seriously badass autox driver, played a game at a track day a couple months ago were he switched back and forth from an 86 to the 8, and said the cars felt surprisingly similar, the 8 having more power obviously, but the general feel was the same. Now THAT is a huger compliment to give a chassis!!