ok...i know what i want to do with my car, but i don't know the route i should take to get there.

my car is an '85 GSL..252,000 miles, it's on its 2nd motor, a mazda factory replacement with around 110,000 miles on it.

i want the car to be streetable, emissions aren't a problem in my area.

currently done to the car...

FC direct fire
interior stripped except dash and original seats. all sound deadening material is removed.
engine is stripped from cruise and a/c and heater
only accessory is the alternator.
shotgun belt
diamond 15x7 wheels
electric fan
ALL emissions removed/blocked off
stainless muffler

what i want to do...
more power, i was going to do a T2 swap, i already have a T2 tranny and stock DP/MP/main cat(to help with boost creep) but i'm still not sure about it.
i only want around 180-200hp(flywheel)
i'm also going to redo the suspension and attempt to correct the rear-end geometry.

is there a cheap/fairly easy way to boost my 12A? or should i rebuild/port it? or should i upgrade to a 13B with a port job and stay N/A, or the used T2 motor or...what? can i use the T2 tranny on a 12A motor without much fabrication?

the car is light, and i don't need THAT much power. but i need a lot more than i have now(probably around 105 considering the miles) i autocross the car every month. 3rd gear grinds. it needs wider/stickier tires for autocross, but my current tires are overkill for the street(215 width) having 2 sets of wheels gives me the option of mounting slicks on the 15x7s, and i'll put some decent 195 width tires on the stocks.

so..what's my easiest/cheapest route to the power i want. which engine/induction combination. and yes..i have considers the V8 or another boinger engine. honestly i don't need the power of a V8, and i want to keep the balance of the car.

 

200 hp, id say streetport and throw on a racing beat exhaust and a better carb

 

You probably won't get to 200 hp with just a street port on a 12a. You can get there, however, with a street port on a 13b. You could also get there with a street port/turbo 12a.

From my own experience, 200 hp isn't cheap with a NA 13b. It'll be over $5000 when all is said and done for me with a rebuilt engine and a Haltech.

The least expensive route is probably a stock 13bT with the stock wiring harness.