So I've been told that I can take my gslse engine and use 12a endplates and then I can have my cheap 13b 4port bridge. Question is what intake manifold will fit? I'm using a side draft weber. so could I use a t2 s4 or s5 lower intake manifold, or the 74-78 RB lower intake manifold. with my rb upper to weber.

Nope; 1st gen 4ports and 2nd gen 4ports have different flanges. All I know of is this...



http://www.mazdatrix.com/pictures/racing/w-ida13b.jpg



2nd from the bottom; http://www.mazdatrix.com/r-idamanifolds.htm

http://www.mazdatrix.com/r-weber.htm

Since I'm using a side draft weber and I allready have part #18100, I think I could just get 18112 and it should work. hmm

actually; I don't think so. Look at the flange differences between the previous manifold I posted, and the TII 4port flange below; I don't believe it will bolt up without modification... and modifying a cast manifold flange doesn't seem like it would be too fun... pictures.



flange you have http://www.mazdatrix.com/pictures/racing/w-ida13b.jpg

later TII flange http://www.mazdatrix.com/pictures/racing/w-idatb.jpg



See how the bolt holes for the front and rear irons are nowhere even close?

You will use a manifold designed for the '74-78 13B. Rotor housings between 4 port 12A and 4 port 13B are directly interchangeable. What you're doing is no more Shelleyan than what Mazda itself did in the 70's when they made the 13B in the first place.



Another way to look at it is that the GSL-SE engine is just a standard 13B with 6 port 12A end housings on it.

yeah gsl-se motor is a parts bin special. the gsl-se engine (and if i remember right the 12a 6 port) had the 86-91 intake gasket bolt pattern. but that stuff is all on the end housings anyways. ramble ramble ramble

http://www.mazdatrix.com/pictures/racing/r9-6.jpg

http://www.mazdatrix.com/pictures/racing/r9-4.jpg

So I'llbe using this then. the top one I allready have and the bottom is for the 74-78 13b. cool. Now does anyone know if a s5 t2 exhaust mani and turbo will fit w/o having to build a spacer?

Looks ad if I'll still need a 2"spacer... how annoying. I night as well build a custom xhaust mani. Has anyone used a tubular exhaust manifold on a stock s5 turbo?

4 ports ar cool but your se motor will give you more power than you think.A huge street port may get you

180-200 hp range(with allot of tuning).A full bridge you can shoot for 250ish.bridge is harder to tune but it feels good to say you just beat them with your original motor,anyway,the se 6 port will accept a newer 6port intake but the center iron ports are smaller and need to be port matched.you will end up with a ramp at the bottom of the center iron's ports where they meet up with the intake.i have done this and it works well but is time consuming.kids crying gotta go



nick

Well it's allready not the origional engine so I'm going all out. I want about 300 fwhp. Thats why i'm going to make it a 4 port half bridge.