waNkLeR

cruzing at 130 kmh (78 mph) is a lofty 4000 rpm
any other ratios out there ?

love the car though its a total blast !
tons of brakes and sooooooooooo balanced !

REDRX3RX8

My 07 6spd auto would be running about 2700 rpm @78 mph, and I even geared it down 3% with 225/40r18 tires.

Z0oMzo0m

iTrader: (4)

my 07, at 78mph is around 4k possibly higher.. i have 225/45//18..


^^ how is yours a 6spd auto...??

REDRX3RX8

The 8 has always come with auto. The early models were 4spd, my 07 is 6spd.

I really like to shift gears, but I don't like all the associated troubles like throw out bearing noise, and 2nd gear synchro grinding.

This 6spd auto is really good on the track because I can concentrate on driving while the car does the shifting.

I don't even use the manual shift, I just leave in gear, it shifts @7krpm, and if I jump off the gas before 7k it stays in gear to be ready for the throttle in the corner.

fyrstormer

My 2nd gear synchro stopped grinding when I put better oil in the gearbox. Chances are, there's still some rubbing and grinding going on even in your automatic, you just can't tell because you don't have a metal rod connecting your hand directly to the transmission. A gearbox is a noisy place to live.

My car also runs 4000rpm @ 78mph in 6th gear. Don't bother me none -- rotaries run 50% higher rpms than piston engines anyway. So to do the math, it's the equivalent of running 2667rpm @ 78mph in a piston engine. That's quite reasonable.

FastFreddy61

[quote=fyrstormer;

My car also runs 4000rpm @ 78mph in 6th gear. Don't bother me none -- rotaries run 50% higher rpms than piston engines anyway. So to do the math, it's the equivalent of running 2667rpm @ 78mph in a piston engine. That's quite reasonable.[/quote]

I think you should reconsider this statement, and your math is wrong.

waNkLeR

it might just be me but....
perhaps the reason the gas mileage on the highway sucks is the gearing ?

waNkLeR

ever had the car "decide" to shift at 9/10ths in a corner ?
thank god for stability control...

i prefer to balance the car and keep in the same gear as god intended lol

REDRX3RX8

Ha! Well ah yes and no. I like my auto because I knew auto was ready made for a smooth and low torque engine with a wide power band like a rotary. I'm retired, weak, and can barely walk, so my driving style on the track is: stomp the gas, stomp the brakes, yank the steering wheel, repeat. It works great on a track with a rotary, and yes, I like the traction control because it doesn't come on unless I'm out of shape.

So right after I yank the wheel, (all at once is the proper way anyway, not slowly turn) I jump the gas. As I'm settling in on the drift after slowing from say 90mph to 60mph, the tranny is shifting down hunting the right gear, and I feel the (low torque remember) power smoothly come in. I did say that the tranny stays in gear when I jump off the gas on a slow speed corner (say 40mph).

The auto doesn't sound like a pure race car, but its my dream car, and the newer supercars are gonna shift similiarly.

REDRX3RX8

Yeah, like ya said sooooooooooo balanced!

Even with 6spd Automatic.

I also got the highway EPA mileage of 25mpg when I drove it to Dallas recently at 70-80mph with AC on.

TeamRX8

iTrader: (25)

It will take a lot of gas mileage improvement to justify the expense, about $1000 or so installed

olddragger

iTrader: (3)

there are 3 rear diff ratios that I know of.
the 4:44---04-08 6 speed car?
the 4:77--S2 6 speed ?
a 4:3 something--the autos?
The s2 trans also will change things for you
lower rpms will improve your mpg--but like team said--may not be worth it.
OD
OD

jasonrxeight

S2 has a taller 6th gear so top gear speed/rpm is the same as S1 only 1st-5th gear are geared down.

TeamRX8

iTrader: (25)

All the FD3 gears, all the SE3P gears, and the Motorsport 5.12 gear

https://www.rx8club.com/mazmart-88/every-diff-ratio-180758/

.

lilring

iTrader: (11)

i belive the 04-08 autos have the 4:10

REDRX3RX8

My 6spd auto has 4.3 like OD said, but with 225/40r18 tires, I now have 4.44 like the big boys.

waNkLeR

i do my own work so that isnt an issue

Rotaman

I changed my rear ratio from the standard 4.4-1 to 3.9-1 and that dropped the revs down by around 500rpm. So now at cruise speed which is around 130kph or about 80mph, my car sits at around 3500rpm. My car is a JDM 6speed.
The gear ratio set that I used was from a fd RX7.
I also hated the high revs the RX8 revved at on the open road. I was used to my RX2 which had a 5speed and 3.9 gears and sat at around 3-3500rpm at around the same speed.

Brettus

iTrader: (2)

You need a radar detector !

olddragger

iTrader: (3)

i put the 09 trans into my 04 model--so my cruising rpms are lower.
i can get 25 mpg with my s.c'ed car.
od