Not to turbo
 

I have been reading forums for some months now and I was very excited to turbo my 8, however, I have done a 180 turnaround. I will not be doing a turbo on this car. I love the idea, but I am uninterested in trying to spend all of my bank on something that will severely diminish the dependability and for the numbers I am shooting for would only put me on par with a 4.6L mustang, without the torque. This car is not a straight line car, it's beauty is in the turns. I am going ahead with suspension, clutch, flywheel, and some other little things, but I have bowed out of the big hp race. I think I would be doing it for the wrong reasons and I would enjoy the car about the same. I am an enthusiast and love the idea, but seriously I bought this car without the need to do anything to it, I loved it off the lot, sometimes one needs to step back and appreciate what they have I suppose. I am instead going to aim for keeping my 8 as pristine as I can, and perhaps do the unthinkable and get something with pistons if I have the urge to go fast, it is simply more dependable. Of course I will never give up my 8.

ok .

^+1

# 4.6L V-8: 315 hp and 325 lbs.-ft of torque

Mild turbo power will put your hp at 300 and torque at 250. You can easily get your torque up higher.

Keep in mind where the powerband is, just because your toque is lower doesn't mean you're slower. My TDI makes 260 torque at ~1600 rpm but the powerband is really only like 2000 rpm wide. The turbo RX8's band will be at least 5000 wide.

^ what he said.

Keep in mind that a 4.6 SOHC Mustang makes 325 ft-lbs at best...at the crank. That equals roughly 275 ft-lbs at the wheels. And yeah a decent turbo on a fairly conservative tune will be down about 30 ft-lbs from that...but weighing about 500 lbs less too. I know I've seen other turbo 8's with more than 250 ft-lbs. But its your car. I was very interested in a turbo for my car too, did my research, and decided it was simply out of my budget and not practical to do on my only vehicle. So now I'm looking into getting a Supermoto next year from KTM. 70 bhp in a 300 lb chassis with Brembo's, WP suspension, and a slipper clutch? Excuse me while I change my underwear please.

It is not out of my budget, I just figure my money would be better spent on something else for now. This is my DD right now and I dont need to jeoperdize that. If I had another vehicle (besides my wife's miata) I be more inclined to turbo. I am actually a bit interested in the 3speed...I have much research to do before I undertake another project, I have too many irons in the fire right now and nothing happens until I am done with the 8. Which it shouldnt be long, as soon as I get home from this sandy vacation..

I was thinking the same thing. Turbo it up! But i think i am just going to get a bunch of extras ignition, wheels, exterior, exhaust like you are with the money i have saved. But it keeps pushing me in the back of my head to get the turbo.

About turbo or not
 

Well i am really new to this form i am going to get an RX-8 once i get home from my contract. I will share my experience. I have a friend that has rx-8 with a greaddy turbo kit the car was a blast with the turbo extremely fast. Now the bad thing fuel consumption was really bad almost 50 % more fuel. Second problem the waste gate on the turbo malfunction the engine was knocking the seals on the rotors got destroyed. All this happen in no time. The RX-8 motor is superior over the RX-7 it is more efficient it runs better it raves harder. But due to the lack of over lap of between intake and exhaust ports exhaust ports cooling with intake air cannot be achieved and if the engine is heavily turbocharged they will overheat due to the back pressure created from the turbocharger. So only mild turbo charging is possible how much is mild i don't know but i am sure you cannot run more then 10 psi without heaving problems with the exhaust ports unless you have some special turbo and special exhaust manifold. ( maybe this can be fixed with a divided turbine housing and equal length exhaust manifolds this is only my assumption i have to study the position of the port opening on the engine in order to be sure if someone has engine timing diagram intake compression power and exhaust in crack revolution please post ). On this engine in my opinion the only way is supercharger because it will not create back pressure on the exhaust ports and they will not overheat. Plus the supercharger output is steady fixed with the engine rpm so there is no chance for over-boosting and it should come with good bypass valve when engine is under low load and good blow of valve for safety when shifting. But again all this cannot be managed by the stock ecu because it is not designed to do it so now you need stand alone engine management and some how you have to connect all the engine sensors to it. On the end you will end up spending over 6000$ on engine alone plus maybe 1000 for installation you will get maybe around 50 % more power but you will compromise on engine live because is high compression 10 to 1 and then you have to upgrade clutch and transmission so it can handle the extra torque. In conclusion you spend over 10 000 to make something that you are hopping to work .

Nevermind, I am an idiot. OF COURSE I AM GOING TO TURBO IT! I just didnt want to spend the money, but seriously guys, I cannot get it out of my head. The turbo just keeps spooling in my head! soon....it will be spooling in my 8!

Ok.

Talk is cheap. Do it! You should get the sequential setup from an FD, it would save you some money.

/\ here we go again LOL

I was wondering about the old sequentials myself. Has anyone done that on an 8?

A pair of small turbos has good potential, but packaging it will be a major PITA and it won't be cheap either

/\ and with recent developments in turbo design (IE the GTX) the benefits over that would be minimal

The aggravation and cost pretty much nixes it for almost everyone any way, which is why you rarely see them rather than a single

Why not to turbo
 

As far as this tread goes it was created for reasons why not to turbo the RX8 engine.
I have to say if somebody likes to put a turbo charger regardless of all the disadvantages associated with this setup on a engine made to be naturally aspirated please do so. But i just want to say if anybody wants to use force induction on RX8 my advice is to look at a super charger kit. This will cause less stress on the engine ( no more problems with back pressure on the exhaust ports created by the turbo) and better boost control because in order to raise the boost you need to change a pulley. I had a friend whit greddy turbo kit that had to rebuild the engine in 8 months after the installation because the turbo kit was not able to maintain the correct boost pressure. Engine knocking was happening and since the greddy kit comes with a pig back controller it didn't work as well as he was hopping for.
Good luck to all.
Alex

I went ahead with a kit I found (of all places) on the FS portion of the forum. Perfect it is not, cheap it was. Greddy it is. I just couldnt pass up the opportunity to have a fight with my wife (it was a bad one). I tried to tell her that we could just call it my christmas gift...wrong answer, she just got more pissed and decided that I have ruined christmas, I assured her I hadnt and that I still needed a clutch and flywheel...I should not have said that...

I hope it is worth it . The fuel consumption will go up and get ready for engine rebuild. You might as well do it when you are changing the clutch and flywheel. This way you will have a fresh engine to play with.

Fuel consumption doesn't increase considerably if you don't continuously push the car.
Why would he need an engine rebuild if the install is done right and the tuning is solid? Lol.

Who will spend money for turbo kit if is not going to push the car. Second this engine is not made for forced induction.Exhaust gases temperature goes up engine firing pressure will go up . There is a danger of scraping of the lube oil and micro seizures that will lead to premature seals failure. Overheating of the exhaust ports is a one more think to take in to account. The increased exhaust gas temperature and back pressure created by the turbo charger will reduce the speed of evacuating of the exhaust gas that can lead to engine damage ( overheating the ports).

dude you need to educate yourself a little more.
You are right that one should be cautious in putting fi on an engine. But you do have some basic misunderstandings.
None of us was born knowing----so study.
OD

Show me some data to back what you're saying up please.
The turbo backpressure\heat debate was started by a company that sells superchargers instead of turbos. It falls in the marketing category.

It is true that you can produce more gasses than the ports can exhaust, it is true that hot spots may deform the side plates and cause engine damage. What flow is needed to achieve that though? Way more than what a t618z is capable of, trust me.
Being a parrot makes anybody sound like a broken record after a while.

Haters will be haters. I realize that dependability may be something I sacrifice, and I would definitely love to build from a fresh and brand new platform, but welcome to reality, I am in the military, I dont make enough to do that. So I found a kit that I could afford. If I blow this wankel, I will rebuild, thats just how it goes. Cross that bridge when I come to it.

I hope it works out well for you.
Good luck with the turbo.

Thanks:balls:

no man--no hating here.
you can build an fi rx8 and have reliability and good gas mileage.
Just get the way to do this down before you start.
od

Absolutely, this is a fun project and I intend to keep it that way. I have gotten some great information from you guys off of here and your suggestions have massive impact on what I do, as long as they are tested and sound. I appreciate criticizm whether it is good or bad. How else would I learn anything? However, with that said, I choose simply to ignore the nay-sayers that from time to time I run into, I dont think they have poor intentions (some do) but simply looking at something negatively is not constructive, it doesnt help me get to where I want to be.

I tend to be inclined take Brettus' advice frequently, at least when he posts I get to see those amazing ta ta's. MM is kinda like the rotary god, most people never get to see him, but he is the all knowing... I assign roles for everyone. Bottom line, I respect everyones opinion. Some more than others, but everything is a learning experience. I am addicted to my little wankel, but that does not make me knowledgeable. I am not afraid to say that most on this forum have leaps and bounds more knowledge on the 8, I seek that wisdom. :angel:

Good luck with your build!
Stoked to hear about it when you're done!

I dont have a turbo but I have ran the SC for a few years.
If I can be of help--i will be glad to share what I have experienced. Just shout out?
OD

I appreciate it! Even though it wont really be anything special. Nothing like a zoom zoom with a turbo!

VERY appreciated...I suppose this stuff seems like childs play to many of you, I feel like a toddler trying to do algebra...slightly better attention span but you get my point. I still have a month and a half before I get back to the states to but I assure you, there will be frequent ridonculous questions.

The rx8 club is like AA for rotary junkies, I love it! The best part is that nobody is trying to get you to quit!

Understandable, but even if youre not doing a crazy 3 rotor giant turbo engine, im more interested in your build because it falls under the category of something I may do in the future. (hopefully next summer) since my car is paid off and tax return is justtttt around the corner.

Again,
Good luck!

Cal