Do the maths yourself if you don't believe me. Using a 1.366:1 3rd gear ratio, 4.1:1 diff ratio and stock 300mm tire rolling radius gives a speed of 12.6mph per 1000rpm in 3rd, so 7000rpm is 88mph. 120mph would require 9500rpm.

If you really are seeing 120mph at the top of 3rd then your speedo and/or tach are seriously out. Have you changed the diff ratio or tire diameter?

 

in my car I hit about 2nd gear at 34-36mph
shift into third at around 64ish 3rd is around 87-92mph and forth tops around 7000rpms for me at around 120-125

 

yup 3rd tops out at around 90 in my car i ride it all the way out at the track never even hit 4th, i'm only runnin 15.2 tho, but regardless unless you revving to damn near 10k you'll never see 120 in 3rd

 

I've got a video of a FC (not sure if its S5 or S4) going to 110.... I remember the thread debating what the top of 3rd is.... and he made that video for that purpose.

I've heard of FB's with miata trannies in them...

MOVIE god dammit... **** a pic. could just have a shifter on it with 6 speeds. I want a VIDEO going from 1-6th... but I believe you anyway.

 

So let me get this straight - an non-turbo FC RX7 has so much power that it can top out its existing transmission and could actually increase its top speed by adding on another gear? Give me a break, NA FCs will top out at 135 on a good day with favorable conditions, whereas the top speed of the NA FC is around 180mph IF it had the ability to go all the way to redline in 5th gear, which it does not. So no, adding another gear would not increase your top speed because you wouldn't have any more power. In fact the only benifit is better gas mileage. And on top of that, a lot of modern Japanese 6-speed transmissions are actually geared pretty short and just have closer ratios with their 6th gears being about the same as many 5th gears in other 5-spd. cars. You're wrong.

 

A little after? Like 8250? S5 NAs had tachs that went to 9000. And believe me, I've redlined third gear many times and the most I've seen is about 95 at about 7500rpm (S4).

 

A guy named Randy Stocker has a website, I believe it's solomiata.com, which has alot of interchange info for Miata's, like putting the six-speed in older Miata's, so maybe there's some info on putting the Miata six-speed in 7's...

 

Uh what about the RX-8 trans? Will bolt right up using modded TII drivetrain parts. A friend of mine has one in his '88 vert. I barely reach 90mph in my 3rd gear. Should a TII trans with a 3.90 rear go higher?

 

Ahh just buy the damn car 400 is less than what I got my engine for!

 

lol wut happened to sam?

 

seeing as how he was debating buying the car 5 months ago, by now he's probably bought the car and gone broke trying to fix it.

 

I think sam went looking for frodo...:-(

 

Erm...I can't believe noone has noticed. Care to explain how an N/A is going to make boost?

-Joe

 

We're done here.