what is the revlimit for a 20b?

 

9k


-Ted

 

9k is right, but I've heard horror stories of taking them over 8500. No first hand experience in that arena though.... I hear with a custom made Eccentric Shaft, you can go over 9k, but of course, that's just net hearsay.....

I won't be taking mine over 8000, 8250 at the MOST.

 

Skunks,
A standard 20B from factory should not have a problem with the right bolt ons to see 8K as a turbo. I have a road race car that is running 9.4K and has no problems with std rotating assembly. This runs dry sump and external oiling system. Some of the drag guys I work with see 10K but not for any prolonged time. The best crank to date has been a factory balanced standard unit. The RPM they will take is almost directly relevant to how straight the factory crank is. We are currently building a crank from same material as the Kryptonite V8 cranks to eliminate flex in the std unit
Regards-Anthony

 

Well, with a custom made e-shaft, 13B's go to ten.

 

Not with a 20B...
That's the standard rule of thumb for the 13B, but the 20B has different natural frequencies that are much higher than a 13B due to the front/middle bearing.&nbsp The stat bearings are also three-window type, so this gives you increased protection for higher revs.&nbsp The 20B rotors bearings are also slightly deeper than FC rotor bearings (dunno how it comparies to FD ones), so this adds even more lubrication for higher revs.&nbsp Like Anthony Rodrigues said, the 20B's will rev up no problem depending on how well balanced the stock e-shaft is.&nbsp I've heard of stock 20B's being able to rev up to 10.5K!&nbsp That front/middle extra stat gear/bearing does a LOT to stabilize the e-shaft on the 20B...

For me, 9K is a good conservative spot.


-Ted

 

the Renisys is gonna rev 10k stock wonder how high ull be able to get it tuned to

 

are those numbers >10g is done with a modified e shaft? or are the rotors lightened as well?

 

Is there something I missed?&nbsp You RX-8 freaks are all getting on my nerves.&nbsp The car hasn't been released yet - why are you all making assumptions on it being able to rev to 10k?&nbsp The RUMORS I've heard puts the redline at 9,000-something.&nbsp This was a 20B thread last time I looked - stop hijacking the thread.


-Ted

 

it wont rev much higher unless they put a center bearing in, or lighten the rotors significantly

mike

 

Not to add to the hijacking of the thread, but this is from Mazda,
"Other refinements, including thinner, lightweight rotors, thicker eccentric shaft, and a three-port, three-stage variable intake system, contribute to the engine's maximum power output of 184kW at 8,500 rpm, maximum torque of 216Nm at 7,500 rpm and a 10,000 rpm redline."

Still not production numbers.

The thicker e-shaft and lighter rotors would also help other rotary engines spin higher. Get a better e-shaft, lighter rotors and balance the package if 9K isn't high enough.

 

Damn, and I freak out at hitting 7000RPM. Mainly due to the auto not reacting to a manual change quick enough.
I keep thinking its going to ovber rev because its hasn't changed gear soon enough, I hate autos.

 

What about yer race car - what do you rev that to?

 

I felt the same thing with my damn auto as well, I was doin' something like 180 and the damn thing wouldn't shift, i could swear it wanted to nail redline.
Is it because i have Overdrive on?

Do you have a 20b, Bitchin7?

 

Bitchn7 has a JC Cosmo, that lucky lucky man

 

Yeah, We have a JC Cosmo,and the missus has decided we are keeping it, sweeeet. So its upgrade time.
Going to put 5 speed in it, large front mount I/C, remove all the emmision **** in the enginebay (so the nice polished engine underneith can be seen), vent the bonnet and next week we are going to try and find some 19" wheels (or 18" if not available or too expsesive in 19") we like and get some and lower it, and about time too.

 

 

How do you get the stock ECU to work without the automatic transmission?

 

evel> I have already tried running the stock computer
with the auto trani computer disconnected, and the
motor runs fine, the trani just doesn't shift, so if now when
I change to a manual I know it will be easy and
possible unlike what some people keep telling you

matt

 

just measure the resistances of the stuff you disconnect, and plug some resistors in there

mike