I AM NEW TO ROTARYS, VERY NEW, AND I HAVE JUST PURCHASED A 86 RX7 WITH A 13B AND AUTOMATIC TRANSMISSION.
IM GOING TO BUILD ANOTHER COMPETITION ROCK BUGGY AND THOUGHT I WOULD GO ROTARY THIS TIME AND WOULD USE THE AUTO FOR SMOOTHER CONTROL.

MY QUESTIONS ARE, I NEED TO WIRE THIS AUTOMATIC AND HAVE NOTICED 3 SOLENOIDS ON THE SIDE. FROM WHAT I AM TOLD, I ONLY NEED TO HOOK UP THE OVERDRIVE SOLENOID. I HAVE READ THE MAZDA SERVICE MANEUL BUT IT DIDNT HELP.
WHAT/WHICH DO I NEED TO WIRE AND HOW?

ARE THERE ANY MAZDA AUTOMATIC EXPERTS OR SHOPS I COULD SPEAK TO?

WHAT FUEL PRESSURE IS THE STOCK FUEL PUMP? I WAS GOING TO RUN A 90 PSI INLINE, IS THIS TO MUCH?

LAST BUMB QUESTION, I WENT TO BUY A AFTERMARKET TACHOMETER TODAY AND WASNT SHURE WHAT I SHOULD ASK FOR. 4/6/8 CYL TACH WHAT WORKS?

 

I'm sorry, in the real world our CAPS LOCKS WORK!!!!

TURN OFF THE CAPS, RETYPE THE MESSAGE, THEN I'LL RESPOND K?

Edit: just read your post, after taking 2 advil for the migraine.. don't have a single answer for you. As far as I know it doesn't matter how many cylinders for a tach. I'm MORE THAN LIKELY wrong, but who knows.

Oh, and good luck crawling up rocks with a N/A auto. You have absolutely NO torque, and the auto trannies in our cars SUCK.

 

I AM NEW TO KEYBOARDS, VERY NEW. AND HAVE NOT FOUND OUT HOW TO MAKE MY LETTERS LOWER CASE. I BOUGHT THIS NEW KEYBOARD, A LABTEC 2001 MODEL, DOES IT HAVE A CAPS LOCK BUTTON ON IT? I'VE NOTICED ONE THAT SAYS CAPS LOCK, WOULD THIS CHANGE MY LETTERING TO A LOWER CASE?


However, on a _slightly_ more serious note, I can't help you with your trasmission questions. I can however tell you fuel pumps have very little to do with how much pressure is at the fuel rail of the engine. You can't buy a 90PSI pump... Basically what flow rate the pump can support at a certain PSI (that your injectors can hold reliably) is what your really looking for.

A 4cyl tach should work fine.

 

Listen to poor red neck. Abandon all hope ye who drive automatic. The N4A-EL in the S5's is a complete shitbox.

And it's the upgrade from the S4.

AUTOMATIC

 

I am going with the automatic for the control. We are penalized points for stopping or clutch rocking the vehicle.
I have heard the 89-91 electronic controled transmissions were crap, but the earlier 86-88 transmissions were very strong but killed alot of power.

We will mostly be rock crawling with it so i dont need the torqe converter lockout, ect. I do need to power the OD solenoid with a switch if i reach higher speeds, but i want to make shure there is nothing else to hook up so i dont burn it up prematurely.

 

So any 4 cyl tach will read correctly?

 

Yes, a 4cylinder tach will read correctly. On antother note about the tranny, they are absolute ****. Im not sure how much power you plan on making, but the US spec N/A auto is pretty weak. There was a Auto tranny available on the J-spec turbo cars. You may want to look into that and see if you could pick one up, as they are supposedly alot stronger, and I believe are geared a bit deeper as well.

 

I dont know what kind of gearing you'll be running with this setup, but I can tell you that you will NOT be climbing any rocks unless it is MUCH taller than the stock rearend. To tell you how bad the stock automatic is, it won't spin a tire from a powerbrake...in the WET. I'm sure it technically isn't correct, but it FEELS like it saps about 60% of your low end power right out. If I am not mistaken you are looking for low end for rock crawling, and you may have come to the wrong place. Rotaries have little torque, compared to even most 4 cyl. motors.

 

Yea, I was going to say something about that, but maybe its a different class than most crawlers Ive seen? Maybe Most people that build crawlers get an engine with the most bottom end torque they can get (big V8...) and put a set of insanely low gears in it. The vehicles usually do not exceed 5-10 MPH, if that. A rotary engine , with an auto, going to a big set of rock crawling tires, would literally go nowhere..

 

I have 8:34 gears in the axles pushing 37" tires. The transfercase also is a 4.16 reduction unit, so the low gearing is there.

 

Well, perhaps the gearing will put you into the high rev;s with the rotary, which is where it lives. Below 3500rpm they are weak...real weak.

 

But the tourqe isn't bro.

 

https://www.rx7club.com/showthread.p...hreadid=230149

third post down i believe. you'll see it, trust me.

 

Thank you for the imput. here is the math to the torque aplied to the rear wheels

stock 86 13b produces 138 ftp torque at 3500 rpm
86 automatic first gear is 2.841
138ft x first gear is (138. x 2.841)= 392.058 ftp
my transfercase low ratio is 4.16
392.058 ftp x 4.16 =1630.9612 ftp

my axles are custom portals with a ratio of 8.34
1630.9612 ftp x 8.34 = 13602.216 ftp of torque at the wheels.

This is more than enough torque for anything and it will keep the motor purring around 3500 rpm at crawl speeds.

This will work!

 

I would love to see a dynosheet of that.

 

off subject but what kind of immautre asses worry about caps lock on or off. and taking to advils for a fake-*** headache is a stale this to say. dam man i mean fukin grow up brow. im sorry to disturb this thread with this but i had to say sumtin to those idiots. LOLLOLOLOLOLOLOLOL!!!!!!!!!!!!!!!!

 

CAPS LOCKS ON THIS FORUM ARE TREATED AS SHOUTING

It is annoying too.

 

caps lock is annoying as hell to the other 95% of people. if you can stand it, congrats, you're in the lucky 5%.
then again, misspelling, bad grammar and punctuation are also noticed. there's a fine line you can easily cross..
"LOLLOLOLOLOLOLOLOL!!!!!!!!!!!!!!!!" << you must not see the line.

 

So does anyone know what wires i should hook up to the transmission and what fuel pressure the stock fuel pump puts out?

 

The stock fuel pump could probably hold 100psi against a closed rail at least...

Not that it means much compared to the price of eggs in china because its a meaningless piece of information without wanting to know the flow rate at that PSI, why do you need to know all this stuff about fuel pressue? we might be able to help you a little easier if we knew that.

The stock fuel pressure regulator only holds the stock pump at around 35-45psi.. not sure on the exact number.. If thats what your talking about.
I've said it before, the pump does not control what pressue is seem at the injectors.

 

If you watched the Monster Garage episode where they had the rock crawler out of a Ford Bronco... whatever V8 they had had something like 60,000ftlbs on the ground.... food for thought against that 16000 figure.

 

I HAVE FOUND THAT THE STOCK FUEL PUMP PUTS OUT 64-85 PSI AND 1.3 GPM. IS THIS CORRECT? DOES THE 13B REALLY TAKE 1.3 GPM? I KNOW MY OLD 90 FORD 5.0 L ONLY TOOK .6 GPM.