That'd mess up your weight balance and polar moment of intertia...

Sorry, had to... since everyone feeds me that B.S. about my car...

 

actually the renesis sits a few inches further back and is more compact than the 13B . Think about the weight that is lost in the rear of the car when you upgrade the exhaust....with the renesis it should even that out to keep the weight 50/50. I REALLY have a great way of skewing the data to match my point. Go me!!!

 

[QUOTE]Originally posted by t-von
[QUOTE]Originally posted by XLR8
IMOP the renesis does not impress me. What kind of power do you consider insane

Quote:

A vehicle doesn't have to be "insanely" powerfull to be fast. 220rwhp in a 2300lb car could easily pull hi 12's in the 1/4 and be street legal w/ emissions.
...

Nope, not easily. A 150-lb driver is part of the math. 2450 pounds, and you're at 13.

Insanely powerful is needed to be 2.9 times as fast as "really fast", but is a different class of speed than "monster horsepower."

Polar moment? Ditch the intercooler, and "Everything goes South in a heartbeat."

 

Yes driver is part of the math however; I still believe the car would be in the 12sec range. Look at this example:

Stock Fd averages 2750-2850 lbs with 255hp. Thats 2800lbs/255=11.2 lbs per hp . Fd's average 13.7-14.00 in the 1/4 mile.

First gen w/Renesis and stage 2 mod would weigh 2300-2400 lbs and have maybe 278 hp. Thats 2350lbs/278=8.4 lbs per hp.

2005 Lotus Elise weighs 2000lbs and has 190hp. Thats 10.5 lbs per hp. The Lotus has run in the12's.

Also even if the Renesis only has stock hp, thats 2350lbs/238=9.8 lbs per hp. Thats still better than the Lotus.

 

Apparently, someone grew a pair and shoved a 20B engine into an SE3P. Nice, but I think it's a step backwards.

http://acostamotorsports.com/

What is everyone's deal with bashing the RX-8? I wish people would realize this is not an RX-7 replacement. The RENESIS makes almost as much power as the original 13B-REW. That's pretty good to me, not to mention the 13B-MSP (high-power) is N/A. Unfortunately, there aren't a lot of tuning options as of yet. I blame the complicated PCM, the difficulty of getting around the S-DAIS, and the extra power ports.

IMO, forced induction as of right now is difficult for the RX-8; it's not like pressurizing previous 6-port engines. The tertiary ports close much later ABDC. Since turbo rotaries prefer to have the intake ports close as soon as possible, high-rpm boost is out of the question, for now. Perhaps the use of an electric-assisted turbocharger such as the one used in the hydrogen RENESIS will help extract more power from the bottom end, not to mention fatten the power band overall.

 

I personally would forget about the RX8 renesis engine and go for a 20B.

Renesis=Slow
20B=Fast


Ohhhhhh.............

 

Hey zerobanger, you do know that the renesis isn't more compact than a 13B right, the engines are the exact same size.

 

The 13B-MSP is more compact than the 13B-REW. The displacements are the same.

 

I was actually thinking about whether this was possible or not either. I don't think there should be THAT many problems.... and why would it not be worth swapping? The engine and tranny are lighter, not to mention lesser miles... just because these older engines are 'better' doesn't mean you can neglect reliability I don't think

 

The renesis isnt reliable , it does NOT take well to boost . so you are stuck with an unreliable engine that isnt designed for a turbo , that does NOT work well with a turbo . and is far from impressive on power .

You can add bolt ons to an FD engine and break 300 whp ,

Bolt ons and ECU and all sorts of crap to the renesis and you are lucky to see 190 whp ,

the lack of torque is frustrating , the transmission is a miata transmission again does not hold power .

the swapping of the electronics is suicidal .



people swap FD / FC TII engines into the rx8 as an upgrade. Sometimes the old engines are just better .

 

i'm not posting to change your mind, but rather to give a little perspective. i think Mazda did both a supremely awesome, and simultaneously ****-poor job with the Renesis (and Rx-8 as a whole). that the engine performs as it does is pretty phenomenal. however, they "cheaped out" with too many things for any rotary die-hard to turn a blind eye. i love driving my Rx-8. it's a blast! however, simple problems have a habit of turning unbelievably ugly with this car and while it may not be fair, i can't think of any Rx-7 I've owned (out of 5) in the last 22 years that have had any of these things happen. anyway, I've digressed a bit.

the lack of torque is no secret and a turbo engine will ALWAYS win that fight. the MSP is not a torque monster? big deal ... Mazda did the right thing. they got torque through gearing. if one goes through the trouble of an MSP swap into anything, then they should do the same.

the argument that the Renesis can't be/shouldn't be turbocharged is akin to arguing that the FD can't seat a family of 4 in comfort ... and can't tow a horse trailer.

i think 190 is a bit misrepresented. the Rx-8 is a car that has 3rd Reich-styled management system. it didn't seem to allow accurate dyno testing early on. i think people have found ways to get around that now and have them somewhere in the 220 range. i may be mistaken though (i don't spend as much time on Rx8Club as i do here).

the engine itself (i'm speaking of the Series 1 engines) has a few physical shortcomings, but it's environment (the Rx-8) also contributed to some of the failures. i think the owners did A LOT of the rest. most, if not all, the physical issues can be overcome. my point is i think the engine itself could be reliable. would it be MORE reliable than the REW? i don't know because one thing to consider is that a stock REW is a stock ported engine with the potential to extract more from it. an MSP, while it is "stock ported", you need to realize that it's basically a big streetport ... AND it has been to tuned to run pretty close to it's limits. a more appropriate comparison would be maybe an REW with the twins making maybe something close to 380 (???).

a lot of what you said is subjective and i definitely respect (and even partially agree with) it. it's a no-brainer that i would put a Renesis in SA/FB, but would i swap a Renesis into an FD - meh ... probably not, but considering i would put one in an FC, i guess ... why not?

 

none of what I said I formulated from driving the renesis , hah 2 of my cousins drive rx8's one has a series 2 , the other a series 1

my cousin with the series one is on engine # 2 .

My cousin with the series 2 the car has been very reliable to him . but I get better mpg's in my FD then he does in his 100% stock car .

I have a friend with a series 1 who auto-x's with me and his car has had all sorts of issues from the secondary ports being stuck closed to the car only putting out 160 whp , after full bolt ons and honestly the whole lack of torque thing I dont even mind . but apparently drag racers do mind .

after being around 3 renesis. I dont find myself wanting for one .. at all ... the RX8 as a chasis on the other hand is SUCH AN EASY CAR TO DRIVE .

i just dont see the renesis as an upgrade to a turbo'd REW . or even an RE .

 

oh, I agree wholeheartedly. it's just that I also don't think they are directly comparable either. they are 13Bs and .... the similarities pretty much stop there.