Me too, but I prefer mine Renesisless

RX-8's are great cars for what they are... fun to drive, decently comfortable and can carry four.




.

 

From what Ive read over the years through a few different rotary specific based tuning literatures, the biggest gain is with the RENESIS internals. Same as some FC 13B parts were reverse compatible and better designed for SA/FB engines, and even more so, REW parts, again being somewhat backwards compatible and better designed/manufactured than SA/FB/FC parts. The RENESIS engines have better balanced, lighter rotating assembly and to an extent better designed gear/bearing/lubrication setup inside.




.If I were to swap a RENESIS into my car (which I am/have heavily considered) it wouldnt be for the power output, but more for the survivability of extended high RPM use with minimal modifications necessary . Iwould run a RENESIS stock short block w/ short runner ITB EFI set up, direct fire coils, header, and a good premix in the tank ad **** pound it all day long

 

the Rx8 engine works are a package, so the intake and block work together. you are correct, the ports are bigger. it does have 10:1 compression but this doesn't gain anything.

the exhaust ports are bigger but don't flow as well, so it makes the engine insensitive to exhausts, ie header does almost nothing.

so changing the intake, i'd have to think you'd loose power, the JDM tuners have actually been putting the Rx8 intake on the REW's, an older 6 port probably wouldn't work, as the Rx8 end irons are a different thickness

 

^^ So ideally, you'd want (for the ultimate motor):
REW housings and exhaust
Renesis irons and intake
Renesis e-shaft
And depending on boost or N/A you'd want either REW rotors (boost) or Renesis rotors (n/a).

 

well for boost you're just better off with an REW engine.

the JDM tuners like to run GSL-SE rotor housings, and block off the side ports.

but really even the stock engine is fine, 230hp is a lot in a 2300lb car

 

yup. honestly if geared right, the stock Rx8 engine is more than enough for most racing, unless you just want to drive around on the freeway and push the skinny pedal mindlessly.

 

i thought about going Rx8 engine when i did the P port, and the P port was cheaper in 2006, but here's how they stack up.

12A P port.
260hp@9000rpm
160lbs ft@8000rpm

13B-MSP
232hp@8500rpm
159lbs-ft@5000rpm?.

so power is close.

but with the MSP, i can put a cat and muffler on it and smog it, with the P port its track only.

 

What are you going to do about the extra exhaust ports on those Renny irons?

 

You use 'em!
Rotary Radness, Mazdatrix's 13B REW/MSP Hybrid!
I'd imagine header piping gets pretty crowded, but I guess it can be done.

 

oh BTW, i was looking for a rattle the other day, and ended up driving the Rx8 around without the radio/nav/climate controls, which are on the CAN network to the ECU, and i'm sure there are some body codes, but no check engine light or anything, so far so good!

btw the Rx8 has a LOT of warning lights, and it can be a challenge to get them all off

 

something has just always seemed so right about a Renesis-powered Gen I. funnily, the earlier comment about the Rx-8 being the next FC is exactly how i'm beginning to feel with S4 rotors and housings creeping upward in price these days. the thought of actually putting a Renesis in a Gen I for myself seems much less scary than it once did.

i'm pretty much a dinosaur, so that CAN-Bus stuff kind of scares me. something like not having a working speedo would probably bother me to no end, but I think I would be mighty satisfied with just using the old Type M and putting the needed Rx-8 gauges somewhere else OR wiring up an aftermarket EMS and calling it a day.

Gravity Fed ~
I really, really dig your friend's car. I also dig his skills.

 

I'll second that, he's got some ***** driving like that so close to a drop off. Very fun videos

 

Given that DA pulled 230+ hp out of a street ported N/A 13b, why would you want a renesis?
Seems like a lot of trouble for mediocre power and a glass ceiling.

 

cost comparison and driveability. I can use the near stock renesis and make between 180 to 200 whp, and it will drive a like showroom stock car. All for maybe 2000 dollars if you look around.

Building a compared 13b Street port would cost far more, and drive much differently.

 

you have a point, but we're looking at it the other way.

for the same $ as a 12A (list price on an Rx8 engine is $2k from the dealership), you can get a 60% increase in torque, 130% increase in power, probably better economy, and lower emissions too.

in CA, if our rules weren't so dumb, the Rx8 engine would be a really easy choice for a have everything car, IE street legal, passes smog and sound, but you can track it too

 

this is sort of one of those things where both sides of the coin are equally important. while more power was made with the older peripheral exhaust engine, you also have to consider and appreciate what DA/Logan is, too. Logan is basically a freak of nature - at least compared to your average Rx-7 guy. while the engine itself was a basic medium streetport, the "package" included a lot of custom work and tireless hours of tuning.

i will speak solely for myself in this regard now. i could probably build an equally good engine, but as for the other things that went into it, i simply am NOT good enough to replicate that. couple that reality with the fact that i love putting in my own work and the closeness between a 230 (at the wheels as i recall) RE or even REW and the MSP turns into a cavern. my guess is i could maybe muster 200-ish from one of my engines (stock manifolds, exhaust, tuning, etc.), my guess is that number would be more inline with the average home or small-time builder that can't weld and has limited resources (not just limited funds), but as we can all see, that is a STOCK number for an MSP. the added attraction is we probably still have a good, long time to look forward to having parts.

at least, that's how i see it.

2 grand??? wow! is that all? what's the catch? also, does that go for Series 2 engines as well?

knowing this now, it simply makes no sense for me to buy a used engine if people are asking $1200-1500 for them.

 

J9 correct me if I'm wrong, but isn't the $2k for the shortblock only? Still not a bad price though, I'm sure the manifolds etc can't be that hard to find.

 

the early 6 port engine is $2000msrp+ $1000 core from any dealership. i think most people just assume the dealer engine is going to be $$$, and to be a little fair the list price is hard to find!

its a mazda reman, so its new seals/gaskets, oil pan, waterpump and flywheel. most come with new rotor housings, but not all. build quality is on the sloppy side, but its cheaper than just buying the parts...

you have to come up with the intake/exhaust/wiring, but that stuff doesn't seem to be expensive

 

as a reman-shortblock your report on the build quality somehow doesn't surprise me one bit. however, i agree 200% that it's better than buying parts to build one. and while i wouldn't have to open the case to do the oiling upgrades, i certainly don't mind going over things (for my own peace of mind) before installing it for use.

every so often i look for intake parts (i think i have a problem ) because being 9 years old and counting, i want to start stockpiling some parts for my 8. anyway, i won't say it's common to come across intake parts, but when you do, you can usually get everything in one shot and the prices usually seem fair. at least, that's been my experience thus far. I've never looked for an exhaust manifold though.

 

yea i plan to be an 8 horder.

 

yeah it seems if your patient the whole mess can be had cheap, or maybe you buy a dead core or something.

its funny i've done 3 Rx8's, and the parts you should stock pile, are the major service parts, coils, and those stupid plastic clips that are everywhere, they get brittle. the fan **** and floor mats are good too. in other words the Rx8 box, is pretty small!

everything else on the car seems to just need a good cleaning, so far Rx8 owners are slobs (no offense), and are cheap! they balk at spending $100 on the coolant bottle, or buying spark plugs...

pic is the ebrake handle, you're looking at the old owner...

 

I wonder if the dealership guys would (unknowingly) take an old 12A, that I could slap together out of junk parts, as a core

 

i dunno about the Rx8 engine, but the REW comes with a tag, with pictures, that has you ID every housing...

 

bastard *** bastards!!!!!!1!!!!1

 

too many people did it for too long