Rotary Car Club

Rotary Car Club (https://rotarycarclub.com/index.php)
-   20B/3 Rotor Conversion.. (https://rotarycarclub.com/forumdisplay.php?f=132)
-   -   How this idea? 20B + RX8 Transmission (https://rotarycarclub.com/showthread.php?t=11354)

TitaniumTT 06-01-2010 12:07 PM

Any competent shop (cough ahem KDR cough) knows about the problems and knows how to deal with them internally and properly. Mazda even had a TSB on it apparently and sells a different linkage that prevents the over extension.

project86 06-01-2010 12:26 PM

Well as of now it sounds like there is a firm grasp on the problem and plenty of competent people (cough ahem TTT/KDR cough) and a way to make it work.... dooo itk!

Renesisking 06-01-2010 02:06 PM

wow, i didn't think it was that much of an issue. How hard is it to not push it further or to fully keep the clutch in until it goes into gear? What is the final drive ratio in the FC/FD? I know the RX-8 has a 4.44 and the second gen has a 4.77. Suppose I did do this swap and kept the stock 8 tranny, would it be fine with the stock 4.44? I think Motortrend had an article where they tested the R3 RX-8 which had the 4.77 gear ratios and they said that other than straight line performance it wasn't any benefit, and that around a track or autoX the older tranny/diff setup was more beneficial and had the right ratios to get the job done.

TitaniumTT 06-01-2010 06:16 PM

Quote:

Originally Posted by Renesisking (Post 119147)
wow, i didn't think it was that much of an issue. How hard is it to not push it further or to fully keep the clutch in until it goes into gear?

Pushing it too far is only one issue. It over extends the hub and bing.... The other issue is idiots grabbing hard and the sync not being fast enough, or the force being too hard and the hub tweaks and bing...

Quote:

Originally Posted by Renesisking (Post 119147)
What is the final drive ratio in the FC/FD? I know the RX-8 has a 4.44 and the second gen has a 4.77.

Gear ratio's in non auto FC/FD are 4.11:1 with a few exceptions.

Quote:

Originally Posted by Renesisking (Post 119147)
Suppose I did do this swap and kept the stock 8 tranny, would it be fine with the stock 4.44? I think Motortrend had an article where they tested the R3 RX-8 which had the 4.77 gear ratios and they said that other than straight line performance it wasn't any benefit, and that around a track or autoX the older tranny/diff setup was more beneficial and had the right ratios to get the job done.

What swap? The 20b swap? Yeah, it'll be fine. IIRC the 8's tires are taller as well which nessitated the higher ratio. A Renni tranny in a turbo or ported FC would be about damn perfect according to my math. We shall see though. But for an auto-x, it would be a JOY compared to the TII box. That thing is miserable for auto-x.... I fucking hate it.

Renesisking 06-01-2010 06:53 PM

Thanks! Last time I saw you at AutoX you were pretty fast. I take it that your ratios are not best suited for that. In most courses I'm in 2nd but I'm just at the lower end of my power. I'm probably around 6000rpms and would much rather be around 7 when all my power kicks in.

TitaniumTT 06-01-2010 07:14 PM

Thanks man.

Ratio's definately suck. I'm high in the rev's in 1st.... 1st! And will occasioanly hit 2nd. With the 8 box in my car I can tool around in 2nd with a TON of torque at my disposal. My torque comes on hard ~3500-4k and holds till 7. Anywhere in that range I'm good. With the TII box I'm either high in the rev's in 1st or bogging slightly in 2nd. I hate that box.

Have you ever raced with FCSCC? Their courses are usually a little looser. I gotta get on the dyno and make it back to CART. Are you going to thier Limerock day? As of right now I'm attending, but waiting to see what happens Friday before I pay.

Renesisking 06-01-2010 07:20 PM

My first autoX was with FCSCC, I really liked them over CART. The courses are a bit faster and not as tight and they're pretty cool about stuff. I'm going to the next FCSCC meet. I'd like to do CART but unless I quiet my exhaust down, it wouldn't be wise for me to show up. BTW, I see whole car part outs on rx8club.com if you want a RX-8 transmission. I'd really like to get a flywheel so that my RPMs cam climb quicker so I'm in my sweet spot more often than not, the only thing is I'm not sure how quickly the revs drop (it may or may not be beneficial as I may lose some mid range torque).

TitaniumTT 06-01-2010 11:18 PM

You will only gain torque by freeing up rotating mass. It may feel like you loose torque off the line but the dyno says otherwise. What you feel is the drop in inertia. Less energy stored in a lighter flywheel...

Totally botched the physics but you get it


All times are GMT -5. The time now is 02:56 AM.

Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2025, Jelsoft Enterprises Ltd.
Hosted by www.GotPlacement.com