RX-8 rear suspension geometry: What changed for 2009+?

Mazda RX7 and RX8 Suspension, Intakes, Headers, Exhaust, Shocks, Springs, Sway Bars, Brake Kits, Autocross and track mods.

RX-8 rear suspension geometry: What changed for 2009+?

Postby JustinM509 » Sun Jan 01, 2017 2:17 pm

When the RX-8 was refreshed in 2009, one of the many changes was revised rear suspension geometry. Does anyone know what exactly Mazda changed and what the effect was?

I understand that several components changed, and that the intent was "better stability" or "better handling." What exactly does that mean? Different camber/toe curves? Higher/lower roll center? Less excess movement? I'd have thought someone would have figured this out and posted about it, but I can't find it anywhere.

The only hint I've found so far is this, from the PDF attached in this post:
Overall driving stability is also increased with a reconfiguration of the rear suspension geometry and by increasing the size of the upper lateral link’s joint section by 7.5 mm for better control of toe-out change at rebound.
Kind of suggests toe control was the point. But the wording makes it unclear whether that extra toe control comes just from the beefed-up upper lateral link or from the geometry revision as well.

Anyone have any input on this? Is there an authoritative source somewhere that I'm missing?
JustinM509
 
Posts: 6
Joined: Thu May 05, 2016 1:22 pm

Re: RX-8 rear suspension geometry: What changed for 2009+?

Postby Brian » Sun Jan 01, 2017 3:01 pm

I likely knew at the time, but 8 years later the details escape me. Likely that answer can be found in searching the bigger RX8 forums with the right terms for threads of that time.
Brian Goodwin
Good-Win Racing
www.good-win-racing.com
Brian
Site Admin
 
Posts: 7677
Joined: Tue Feb 15, 2005 11:44 am
Location: San Diego CA

Re: RX-8 rear suspension geometry: What changed for 2009+?

Postby JustinM509 » Sun Jan 01, 2017 3:37 pm

Thanks, Brian. Happy New Year, by the way! :]

RX8Club has turned up zilch so far. Also searched Nopistons. Found a few comments here and there on other forums (e.g. here) but no authoritative sources. Guess I'll keep looking...

Any pointers on where to look?
JustinM509
 
Posts: 6
Joined: Thu May 05, 2016 1:22 pm

Re: RX-8 rear suspension geometry: What changed for 2009+?

Postby Reitrof » Sun Jan 01, 2017 8:00 pm

Just throwing something in here but wasn't the suspension tweaked in the NC in 09? They share the same frame.
2008 PRHT Touring True Red, MazdaSpeed body kit
RSII, RX8 Sways, KW V3 Coilovers
Kenwood DNX7100, Nautilis Horn
Reitrof
 
Posts: 83
Joined: Sun Aug 20, 2006 1:36 pm
Location: Carleton Place Ontario

Re: RX-8 rear suspension geometry: What changed for 2009+?

Postby JustinM509 » Sun Jan 01, 2017 8:35 pm

According to this, the geometry change on the 2009 NC was in the front suspension, not the rear.
JustinM509
 
Posts: 6
Joined: Thu May 05, 2016 1:22 pm

Re: RX-8 rear suspension geometry: What changed for 2009+?

Postby Brian » Tue Jan 03, 2017 2:40 pm

That sounds right, because it would match what happened on NC2 Miata. Bottom line on those changes is that most did NOT find it worth the trouble to swap their NC1 Miata to the later NC2 bits up front, but if going to compete at Nationals then it might be worth it. It required we redo our front springs for NC Miata to get the heights right at the front.
Brian Goodwin
Good-Win Racing
www.good-win-racing.com
Brian
Site Admin
 
Posts: 7677
Joined: Tue Feb 15, 2005 11:44 am
Location: San Diego CA

Re: RX-8 rear suspension geometry: What changed for 2009+?

Postby DustinS441 » Wed Jan 04, 2017 6:40 pm

I discovered this on rx8club.
"New Rear Suspension Control Links (Rods) Upper/Lower and Trailing Ball Joint wrist area increased in Diameter/Size.
New Rear Stabilizer Bar. (R3)
New Rear Shocks And Springs.
New Rear Axles (Manual Trans) 3mm thicker diameter..
New Rear Suspension Knuckles."

From thread: http://www.rx8club.com/series-ii-techni ... ii-161665/

This lists a lot of changes (perhaps all mechanical changes) between the first and second series Rx8.
DustinS441
 
Posts: 3
Joined: Wed Jan 04, 2017 6:18 pm

Re: RX-8 rear suspension geometry: What changed for 2009+?

Postby JustinM509 » Fri Jan 06, 2017 9:30 am

Yep, saw that post. It's basically the same list as the one I linked, BTW. Same thread author.

I already know the parts changed. What I want to know is how the changes in the knuckle and upper lateral link change the rear suspension geometry.
JustinM509
 
Posts: 6
Joined: Thu May 05, 2016 1:22 pm


Return to Rotary Performance

Who is online

Users browsing this forum: No registered users and 1 guest