Good morning RX-8 Club!

I have been publishing a series of videos on youtube detailing what i've learned from you all and from my experience in owning two RX-8s over the past 12 years, focused on first making your RX-8 reliable, and then on reliability upgrades and the basics of performance modifications. I am starting this post to do something dangerous: invite public feedback! I've already noticed an error or two that require corrections, but rather than delete a useful video i plan to link all of the videos here in a running "Corrections, Comments, and Clarifications" discussion board. I will embed each video below as I publish them so you all have them handy, and then I encourage this smart community to contribute their perspectives as posts in this forum. I will compile feedback into this post under each video title below.

Thanks for helping in my goal to give back to the community, to instill enthusiasm in the RX-8 platform for the next generation, to save RX-8s from the scrap yard, and to educate folks on this under-respected and under-appreciated platform!

BASIC MAINTENANCE AND RELIABILITY UPGRADES

• Addition: The OE starter on the early (04 and 05) RX8s was a bit weak. The 06-08 starter was an up-rated 2.0kW unit, and the S2 09-11 starter was an even bigger 2.6kW unit. Each provides better starting power but adds a little bit of weight.
• Addition: The OE oil cooler lines can rust and fail. Individual sections are still available from Mazda, although numerous aftermarket vendors offer stainless steel braided hose kits with -AN fittings.
• Addition: The vacuum solenoids behind the intake manifold can crap out. You'll get a CEL and may loose SSV or VDI functionality.
• Clarification: At least one racer has recommended AVOIDING differential oils with limited slip (LS) additive; "the OEM tochigi fuji diff needs all the friction it can get".

RX8 POWER MODIFICATIONS

• Addition: Not sure how i missed 20B (3-rotor) and 26B (4-rotor) engine swaps. They are definite possibilities (see Revolution RX-8 JDM time attack car), but the costs seem to be in the five figures range.

RX8 SUSPENSIONS AND ALIGNMENT

• Correction: Mazda appears to offer all of the bushings for the front lower control arms, but does NOT appear to offer bushings for any of the other arms.

RX8 WHEELS AND TIRES, CHASSIS, BRAKES, AND DRIVELINE

• Addition: The shifter boots and seals between the shift lever and transmission can wear and result in noise and heat.
• Addition: The rubber seal between the shift retention plate and the transmission is not available separately from Mazda, but i cut my own from high temperature rubber seal stock and it is working great. Save $60!
• Addition: 245/35/19 = stock STI tire size. 235/35/19 = slightly better acceleration but slightly worse availability.

RX8 AERO, WEIGHT REDUCTION, AND MISC

• Addition: Lightweight batteries - beware. The RX-8 alternator control seems to have issues if too small a battery is utilized, potentially even impacting ignition strength and horsepower. Plus, the RX-8 is generally a little tougher to start than equivalent piston engines, so they generally start more reliably with a larger battery. Lastly, the ~70-80mA current drain will drain down smaller batteries quickly if not kept on a tender.
• Clarification: The weight of the Series 2 R3 seats is under some dispute. Gears and gasoline stripped out an R3 in a youtube video, weighing each compotent, and they got 48 pounds. But ShiryuStrider made the same measurement and got 37 pounds.

OTHER NOTES

• Recalls (http://www.rx8help.com/recalls.html)

 

 

Hey man.. I watch your videos on YouTube. Good going. Thanks a lot. There isnt much new Rx8 content on line

 

Thanks, BluRR. That's the thought - try to give new RX-8 folks a good starting point.

 

Latest video added.

 

Pretty insightful stuff. I'm gonna refer to your video when I get around to doing suspension mods.

 

Thanks man. regarding springs rates and stiffness, i've always felt like i regretted going too stiff more that i regretted going too soft. you can adapt to and compensate to some degree for soft springs (see Street class autocrossers!), but an uncomfortably hard suspension will never stop punishing you (unless you only trailer your car to smooth tracks!)

 

Thanks for making these! Last year, I was deciding what platform I wanted for autocrossing and was torn between an RX8 or FRS, and finding your videos and watching your runs was a big factor that pushed me to the 8! I’ve had it for a few months now and couldn’t be happier.

 

welcome to the club! the FRSBRZ are nice cars and have some advantages, but their suspension and mass distribution just aren't at the level of the rx8. Plus our engine character is so much more enticing. I think you made the right call. 😉 what sort of prep are you targeting?

 

The initial plan was starting CS then working up from there as I got a better feel for the car and what it needs, but I’m finding the car may already be in a higher category despite “stock” claim it was sold as. It’s a 2010 Sport, but prior to my purchase they swapped in the R3 interior and wheels, and I’ve found that it has the aluminum undertray and some no name lowering springs. So far, every time I’ve worked on it I’ve found new mods, so I’m trying to decide where to go from here. Either way, I’m not competitive yet, so no real concerns one way or another.

 

if you swap back to OEM springs, i doubt many people locally would balk about the other mods. the R3 seats and aluminum undertray add weight. if they were lighter, people might complain. and the 19" wheels (+/-1" diameter change from stock) is acceptable (but not ideal) for CS. So i'd say throw some OE springs on and you're probably good.

 

Just weighed my R3 Recaros this season they came it at 37lbs with the rails attached which is about how much you said the stock cloths weigh

wondering if the S2 leather GT seats being 50lbs is accurate
i have a set still in my car which I will weigh come spring when i swap them

 

50lbs sounds like it makes sense. Leather, heating elements, and adjustment motors would add up fast.

I’m surprised the Recaro seats are the same as the sports. I always figured they’d be lighter.

 

when "gears and gasoline" stripped out their S2 R3 on youtube, their scale said the recaros were heavier than the s1 base model cloth seats. not sure if the R3 recaros changed over time. but i will add a note to say that the weight difference is disputed.

 

The last video in the series is live! I certainly appreciate all of the information, knowledge, and most importantly wisdom that this community has shared with me over the years, and i have been happy to try to condense it and share with others. Let me know if y'all continue to identify any corrections or clarifications.

 

I have a few questions about the topic of wheels.

You stated in your series your noted advantages and disadvantages of a 17" vs 18" wheel. One of the points you highlighted was the power (or lack therof) in a "stock power" Rx8. My question is, for individuals with forced induction would you say the difference on some of the disadvantages of a 18" wheel become negligible for any Rx8s with engine swaps or forced induction that are lets say >300whp? Or would the 17" still be better to choose for the reasons you pointed out? Are there any specific use cases where a 18" wheel would be the wiser choice over a 17" wheel?

 

When you go forced induction and >200WHP, yes i think the situation starts to change. in most cases, you want more rubber and can use more rubber with more power. 17s generally top out around 255s, although there are a few 275s out there. so yes, i think at those power levels going to a 265/35/18 or 285/30/18 or even 295/30/18 would be beneficial. There are really fast NA renesis RX-8s in Japan at say Tsukuba who are lapping below 59 seconds on 265-295 width tires, so with forced induction i think that's a good starting range. in my experience the car handled nicely with 18s especially at autocross but I didn't REALLY feel like i had the horsepower to take advantage of them on high speed circuits.

 

You spoke of different wheel fitments for the Rx8, some of which used a very wide width. Would you be able to clarify if those were staggered or squared setup on some of those extremely wide fitment guides?

 

I am not aware of anyone running staggered fitment on competition vehicles. i guess if you went really big on power, you might consider it. The disappointing thing is that mazda gave the RX8 the ability to swallow up gigantic tires up front but we are a little big limited in the rear short of rolling, pulling, or flaring fenders. not sure why mazda made that choice. even the fast time attack guys in japan seemed to be running 295s up front!

 

just rewatched the video ben showed himself weighing it with a luggage scale at 48lbs, i dont see how this makes sense when the normal S2 with the motors and memory function is supposedly 50lbs

i guess i'll have to make a video of myself weighing it

 

I see, I ask because in the future I'd like to ditch the Work wheel reps I have for a nice lightweight wheel in a 17x10.5 or 18x10.5 squared setup, but I'm trying to find exactly what would be a ideal offset for that wheel width. I have rolled fenders front and rear, was thinking like a 265/35 tire setup on that 10.5 wide

 

i've never seen a 17x10.5 wheel - i think you might have to go custom. But Falken and nankang have 275 width 17" tires so those would probably work pretty well for FI.
18" wheels have MUCH more selection for both the wheels and tires when going big. A 265 would be fine for FI and street driving with a 10" or 10.5" wheel, although a 285 would also be a good choice if you don't mind rolling fenders.

 

18x10.5 squared with a 285 squared setup? Could that much tire comfortably fit up front with a proper race alignment and setup with a proper height for track use? That might be the idel setup to pair with the extra power. I havent gotten too far into my tuning yet (my fault), but my goal is to get as close to 400 as i possibly can. Grip is becoming very important to me.

 

i know it sounds crazy brother but the rx8 can swallow up huge rubber up front. Ken Houseal has seen the same thing when test fitting crazy setups on his racing rx8. i think if you're around 13.5" ride height with healthy camber that setup should work. that said, the biggest i've gone is 17x10 +38 and 255/40. those fit with no front fender mods. it's possible you'd want to roll your front fenders. The offset might determine whether you'd need a steering limited up front too. since you're getting outside of my comfort zone i recommend checking in the RX8 Racing section and/or on rx8 autocross and roadrace facebook groups to talk with others who have run similar setups. The SCCA DSP builds typically fit 285+ rubber.

https://www.mazdamotorsports.com/201...d-tips-budget/