6/4 port
 

i'm planning to bulid a n/a street-strip motor....13b should i go with 6/ or 4 port...whats the difference???

For max hp and porting and assuming you are using pre-86 engine parts, go with the 4-port. You can use 12A end irons since the old school 13B 4-port end irons are getting extremely hard to find.

yep...scott's right....all the puerto rican's around here call them "cracker jack" motors (13b with 12a irons)...don't know why...but still...

4port all the way

13B displacement question.
 

what makes a 13b compared to a 12a 1100cc.?what becomes bigger?

the rotors and rotor housings are thicker, along with a longer eshaft. essentially making the whole engine longer than a 12a.

so it's possible to use the end and center plates for the 13b.?what else can you use from a 12a for the 13b?

Not sure exactly what you're trying to accomplish? The only the 13B housings and irons from the SE will work with the 12A parts. Most people use the SE housings and the 12A irons to make a 4 port 13B. 12A=1146cc 13B=1308cc

Not just the -SE. Any pre-'86 13B has irons, front cover, etc. interchangeable with 12As.

I ain't trying to acomplish nothin..I was jus ready to thrash a 12a and thought I could salvage some parts for my 13b

yes u can use 12a intermediate plates with pre '86 13b rotor housings to create a 4 port 13b.

Searching using 13b 4 port as the key words may shed more light on this.

Holy thread merger. Yeah I should have stated pre 86. Sorry.