12A six port troubles
 

Hi everyone,

due a engine fail of my previous engine i recently installed a 12A 6-port engine in my 1984 FB, after some trouble with main pulley and timing issues it runs nearly smoothly right now, but i've got one serious problem, the 5th and 6th port arent actuating cause i have a RB header and not the original exhaust wich powering the sleeve actuators.

Does someone has good ideas for making those actuators and sleeves mechanical actuated or electromechanical?

Anyone who has some data about original emission-control system for such a engine?

i run my 13b 6 port with the sleeves totally out of the intake, and tuned my dellarto around the fuel needs at low end. runs really good.

I have access to some 6 port 12A stuff. From what I can tell, you are correct it uses a long tube inside the stock exhaust manifold to actuate the aux sleeves through a hole in the rotor housing under the main peripheral exhaust port. I believe it shares the ACV port with emissions devices. So I'd suggest adding a tube to your RB header and connect it to the ACV block off plate, if you have one. Obviously you do because you have a header. :)

I had a pacestter header that the previous owner put a tube right where the collector joins together.
The Back pressure was great for port activation there.

exhaus pipes comes together above the rear axle, that means i need a real long tube :lol:

but i rather don't want to break down my beautiful header, so i'm gonna look how a mechanical linkage with carburator is gonna work, take a try to link it on the secondary's

@Jeff20B, in your 6-port parts, do you still have that plastic vacuum part between intake manifold and carburator, i've got one with the engine, but thats one for automatic transmission :D you can recognize it by an single counterbored main passage in on the downside.

thanks everyone for thinking with me :)

If you're talking about the phenolic spacer, I believe I still have it. It has nothing to do with aux port actuation as far as I can tell.

Thats right, it's just a question apart, because the phenolic spacer i've got is for automatic cars with one ignition advancing port, i've got a manual gearbox. can i get a picture of it? does the six port engines have a specific carburator or just the normal ones?

about 5th and 6th port operation, should it work if i make a passage in my exhaust header flange to the pressure ports? flange is about 3/8'' or 10mm thick

If you check the 2nd gen FAQ, you'll find links to activate the aux ports via an RPM switch and air from the air pump.