serf2

I have a 13B that I bought about a year ago. Back in 86 it was rebuilt by Tri-Point crated up and shipped to the fellow I bought it from. It has a Holley 600 series carb and a custom header that was shipped with the engine. When it was rebuilt it was dynoed at 220 horses. The fellow I bought it from never uncrated it. He would pour a little oil in the sparkplug holes once a month and turn it over by hand but that was it for the next 15 years. I installed it and have sence started it and it runs and sounds great.
What I would like to know is what year it is and did it org come out of a RX7 or what. Do they have a numbering system or some way of telling?
Any and all info will be much appreceiated. Thanks Mark

moremazda

iTrader: (4)

If has only four intake ports, it is a 74-78. But its completly possible to be a bastard engine also, 12a side plate early 13b rotor housings 89-91 N/A rotating assembly.

Any way check the number of intake ports 6 is 86-91 non-turbo, 4 is 74-78 13b, or could be 87-91 turbo, but not a very likely build, essspecialy with 220 horse. Now that's a Noble Prize winning sentece.

Ryan

peejay

if it was built in '86 then pretty much guaranteed it's a '74-78 4-port. I doubt that they'd use the then-brand-new '86 rotors, and Turbos didn't come to the US till mid '87 so it can't be a turbo engine.

Actually that's not entirely accurate... when 4-port 13B's and 12A's were made at the same time they shared the end plates, the only differences were rotor housings, manifolds, and rotating assembly. You could easily make a 4-port using 12A end plates in a GSL-SE engine. You wouldn't even need all of 'em, only the two end ones, that way you could also rig up a fuel injection system easier because of the injector bosses in the -SE center plate.

serf2

Well it only has 4 ports. If in the futore if I want to or need to order any parts like say a water pump or intake gaskets is there any differants between the 74 78 13B and the later SE 13B's? Also sence it is only a 4 port does that mean that it must of had a pretty radical port job to be able to dyno at 220 HP? Thanks again for the info. Mark

peejay

You might be able to get away with ordering stuff for a '74-85 12A for anything except stuff related to engine length (manifold gaskets, oil cooler lines, oil pan gasket).

Yes that would be a pretty nice port job to do 220hp! Fairly decent street port, free flowing exhaust, and good carburetion - and any deficiency in one place will have to be made up in another (so if that's 220hp with open headers expect 180 or so with a streetable exhaust)

Rotor13B

What about the 84-85 13b's? were they four port or six? And if they were six, did they have the port actuators ?

Siraniko

iTrader: (13)

the 84-85 13-bs came out from the gsl-se. they are 6ports as well but the rotor housings have same configuration as the 4port's. just get the 12-a cast irons to convert the block to a 13-b 4port.

and yes, they have actuators too.