I am a complete noob when it comes to Mazda rotary engines. Having just purchased a 13b conversion car, I am lucky enough to have found this one which runs excellent.

I am 95% sure that this car is running a Holley, but there are no distinguishing markings anywhere on the carburetor.

Here are a few pictures:

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Is this enough for someone out there to say, "yep that's a Holley"?

The only strange characteristic of this carburetor is when I aggressively accelerate up to the 9k RPM range, it will sometimes sputter as I let off the gas like it runs out of fuel. I am assuming that this is a problem with the fuel pump being able to provide enough fuel pressure to flow at that RPM.

Reading online I see that most of the racing/high performance rotary guys run a fuel surge tank. Could this help cure this issue, or would a slightly higher performance pump with a good fuel pressure regulator cure the fuel starvation problem?

I currently run a Carter fuel pump that is probably old.

I'm thinking that is part of a fuel injection system....

Not sure how that would be possible?

It's definitely special for the rotary. I would run a high flow pump with a return regulator to keep the pressure low enough for the carb.

Wait, I would replace that with a 48 IDA single down draft carb and manifold.

I don't think you can go out and buy a new double pumper and get it to work correctly. I will say there is quite a bit of polishing in that top hat.

Parts are impossible to come by at your FLAPS. You will need to mail order most of your parts. I used to get a lot from Atkins Rotary. http://atkinsrotary.com/store/

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Thanks..lol

I think Mike is the winner winner here. Looks like a heavily modified/ported Nikki carb.

I think I am going to run a fuel injection system using somthing like these:



http://www.borlainduction.com/throttle-bod...components.html


I will run Megasquirt or there is a simple cheap solution through a company called Ecotrons.

http://www.ecotrons.com/products/wankel_en..._injection_kit/

i am running a Holley Blue fuel pump knockoff on my Bugeye Sprite with a 13B in it. I am switching to fuel injection in the next few weeks, you are welcome to the pump and regulator if you want it. Send me a pm and I will drop it in the mail. 13B's use a lot of gas, they need enough volume to make it run correctly. Ed

^ sweet ^ Pictures please!

What are you doing for fuel injection?

I am running a Jenvey Throttle body, racing beat intake, MegaSquirt MS3 Pro, and a Walbro fuel pump. It is sitting in a box waiting for installation. The engine is a large street port. I wired the actuators open and am still using the oil metering pump. I will start on it in a couple of weeks.

very cool. I would be interested to see your set-up completed.

I have little to no documentation on this engine, but based off its idle I think that it is bridge ported. I like the idea of getting more fuel efficient with FI, and I read you can get a more usable torque curve over carburetor.

I will send you some photos when I get it going. There is a very good write up from a guy named Aaron Cake at the rx7 forum about doing a MegaSquirt conversion. It is worth the read.

If you keep the distributor and coils, you can use megasquirt. If you want ignition control you will need to go with a Haltech rotary ECU or similar.

Wow, looked on their website. $1,700 with the wiring kit. Pricey.

I am doing both ignition and fuel with the MegaSquirt 3 pro. I am using a Full Function Engineering crank drive with the RX 7 coil pack.there is a bunch of data on DIY fuel injection

Mat, I have a crank angle sensor (looks kind of like a distributor) to replace the distributor if you go with ignition timing. I don't think I have any other rotary EFI stuff anymore. I sold it all off. But my blown motor has the crank sensor intact. You can have the blown motor too. Just needs an apex seal.

Free blown motor! Sweet!

Thanks Mike, at least I can pull it apart and learn about these motors.