just got a 09 rx8

[Nutsid]

Originally Posted by reddozen

Nutsid,
I have no interest in arguing the accomplishments of over 20 years of research and trial an error on the 13b, and over 30 years on the 12a. A few people have experimented with the Renesis stuff, but it's been nowhere near on the scale of the 13b or 12a. In fact, in basic design, they're both damn near identical in functionality, so a lot of the same porting concepts carry well between them.

So you can say what you want, but until the Renesis gets the same attention as the other two, your point is rather unproven. The design is sounds, and if you're that hung up on 4 port design, then there's a Renesis for that too.

What I think needs to happen is more investigation into the irons, and their overall use / effectiveness, and a possible standard modification / redesign. The engine is far from ineffective, and to say that you're better off swapping a 13b-anything simply because "this one guy, that time, got like... 800 HP from this motor" is a waste of money and resources. If your goal is 600+ then you need a 20b and be done. Otherwise, you cant justify the expense and time on an engine swap when you yourself said that people have gotten the Renesis engine up to 500+ HP. It's cheaper to boost and tune an already owned / installed engine that it is to start from scratch, and that's not debatable due to the fact that, not only would you still have to buy all the FI accessories for the new motor, but you'd have to buy and rebuild the new motor, fab mounting brackets, most likely a new transmission, stand alone management, etc. You could never justify the added cost to me.

rebuild kit: $1000
Bridge Port: $500
Tuning: $500

custom super charger setup: $1500

For $3500 I can make over 400 WHP in my car by doing most of the work myself, and for most people that's more than sufficient. Like I said, if you start getting into the 600 HP range in terms of goals, you're better off going 20b, so a 13b swap makes no since.

You really don't have to argue the point. The porting rules remain the same throughout the rotary world. The more open area to allow air and fuel into the combustion chambers, the more power. The way the intake ports are setup on a Renesis don't allow for a whole lot more port work to be done. You'd be able to do a bridgeport, but unless you go with an aftermarket ECU, that will just cause all sorts of problems. And for a good one of those you're looking at a grand or better.

Another thing to consider, a good rebuild kit using OEM parts for the rebuild is going to cost more than $1,000. I should know. A 12A's rebuild kit is over $1,100. I've also done port work myself before and I can tell you with absolute certainty that a good reputable company will charge more than $500.

Regardless, let's say your numbers are correct. For 3,500 dollars you could easily do a 13B-REW swap into an Rx8 if you do the work yourself, up the boost, and have full exhaust. That will be more horsepower than the Renesis guaranteed. You'd still have enough money left over to buy a rebuild kit, crack the engine open, and bridgeport it if you really wanted to show a Renesis powered anything what was up.

I have absolutely zero complaints about the Renesis. I love the engine. But to say it is even comparable to the capabilities of the 13B-RE and 13B-REW is laughable at best. There is a great reason why it isn't popular whatsoever to "build" a Renesis. A lot of work for minimal gains.

I'm not in the mood to research cost of superchargers and turbocharger setups for a Renesis. I know when I previously looked into it was outrageous. For 350 horsepower it was something like 4,500 dollars for a turbo kit or something stupid. And then I'd have to get the engine management system and all the other stuff as well. Completely not worth it when I could get a 13B-REW with good compression and good turbos for 1,300 dollars and all it would require to have that kind of power is a good tune for 14 psi, or upgrade to a semi-decent single turbo and not have to deal with the complicated twin turbo setup. Or go one better and do a 20B swap, keeping the turbo on it... since, you know, they came from the factory with over 300 horsepower.

But to each his own. I know the Renesis can make the power (to an extent). Its just not as reasonable of a means to make the power as can be had through the 13B-RE and 13B-REW.