I am building a N/A bridgeport hybrid engine for my 85 gen1.
How should I do with the waterseal jacket?
Fill the rotorhousings jacket with Dewcon??
Would that work if I get the surface flat?

 

bumb

 

I wonder if JB Weld would work..???

I never heard of Dewcon..??

 

I would say give it a shot. After all the BP housings are what you want to protect. Just us a light dab of silicone along with the rings just to protect against surface imperfections of the epoxy. It should hold up for a couple thousand miles...(read 15-20)

Good luck.

 

He means devcon.

If you are porting past the water seal, run your coolant line normally but cut it before/after the seal and steak it down, so it will not pull into the chamber and flood it with coolant. You can fill in the water jacket and remaining coolant groove with the devcon. When the devcon has dried, and you are puting the engine together, run a bead of silicone sealant around the port, attching the 2 ends of the coolant seals together.

Picture is for devcon reference

 

I thought he meant using 12A rotor housings with say.... newer S4 irons. Both have the provision for the waterseal so one of em would have to be filled.

But he did mention bridgeport also...

 

Im reading the same thing your are...the 12a housings and 6port irons have the water seal grooves...maybe he miss wrote the title or something...

But the pic and description up there is correct...great post Mr.J

 

He is planning to use 12A housings with S4 or S5 6-port irons. The hybrid engine is going to be bridge ported.

 

or he could be talking bout using irons from a gsl-se.

 

Sorry! I have to make it clearer...
I will build the engine with 12A rotorhousings and use 13B 6-port irons from a N/A -88.
The water seal grooves on one of the parts need to be filled with Devcon, or something else that will stay in shape when the parts will get warm.
I will not port passed the groove, but it will be a BP. I think the 6-port irons will give me the flow I need without monsterport. I want the car to be possible to use on the street...

 

Don't bridge the aux ports. Rotarygod will send you flies and boils if you do.

I believe Devcon will hold up well in the irons so you can purchase the cheaper '85 and older coolant seals that fit in the rotor housings.

There is an aux port casting "lump" in the way on the 6 port front plates right where the front counterweight spins. You will need a late 12A rotating assembly whose front counterweight already has a nice 45° bevel like the FC front counterweights. Yes Mazda was thinking ahead and did actually make a 6 port compatible 12A rotating assembly. I'm building a 6 port 12A myself soon and researched this. Plus I know they were sold in Europe.

 

Do you think you will get a little more power out of the 6 port? Or will it be just more usable power?

 

Better low RPM torque, like a 13B, and better high end power like a streetported 12A.

 

That sounds nice! Making a thread when you get it going?

Ok, I am going to stop threadjacking now

 

Why not? I have done it on a Lotus Super Seven engine (13B 6-port) and it runs perfect.
280.5 hp on the flywheel...
The front one on the pic is the one I made, the rear where the customers broken...

It's a 1984 12A,

 

I would love to know if this has been done before??
Building a hybrid of 12A and 13B...

 

you could just run both water seals too, not the cheapest way, but its simple

 

I will use Devcon on the rotorhousings...

 

Personally, I'd run 13B housings with 12A end irons, both from 1st gens. Another option is building an NA TII. If you do run 6 port end irons, bp the aux ports only and have working 6th port actuators if you want to keep any semblance of low end torque for street driving.

Devcon may work, for a while, if you must mix and match 1st/2nd gen housings and irons. Another option is Lab Metal, pricier but should hold up better. There's a guy on nopistons.com that explains how to deal with the coolant seals if you go with a monster bp that cuts into the seal groove. That site seems to be offline atm or I would give you his name. However, I have yet to see anyone even remotely recommend building an engine with 2 coolant seal grooves.