jaidedeye

without opening the motor how much HP it attainable in naturally aspirated form?

here are my engine mods:
85 12a with 40k miles on rebuild (stock port )
RB race header
RB streetport exhaust (header back) with magnaflow muffler
RB intake manifold (upper/lower)
mikuni 44 side draft carb's
carter fuel pump
holley regulator set @ 4.5 psi
all emissions stuff removed
air conditioning removed
E-fan

now i know that i could def improve my ignition system but other than that it looks like thats it ...or am i missing something?

peejay

150.

You can do this with the stock exhaust manifold. The restriction is not the exhaust system, it's the exhaust port. Good tuning is what you need.

Whizbang

that is basically what i am trying achieve now.

short answer: fuel injection.

jaidedeye

thanks guys.

im just very intimidated by opening up a rotary to port the housings. ive built push rod motors in the past with great success but a rotary kinda scares me. my 12a has low miles on it and was built by a shop in ohio. if i was to tear it apart and port the housings, would i have to replace all the seals/bearings etc as if it was a fresh rebuild?

Tom93R1

iTrader: (2)

Soft seals should be replaced yes, that whole kit is only a hundred something dollars. Hard seals it depends on how worn they are but probably not. Bearings would most likely not need replacing

Whizbang

Pete has shown me exactly how much CAN be reused when rebuilding. Although the apex seals themselves is a worthwhile component to replace unless your flat *** broke or you happen to have very nice unworn set when you crack the engine open.

Also helps to try to keep parts where they came from...but that is not the top at hand.

j9fd3s

iTrader: (3)

most of the engines ive been taking apart recently, need side seals and bearings.

the rotor housings are usually worn to the point where putting new apex seals in would be a waste of new apex seals....

at 20k though, anything replaced last time should be nice still, you just get to change the stuff they didnt

j9fd3s

iTrader: (3)

oh and if you really want max hp, yawpower's got a good write up on how to do it

http://www.yawpower.com/goodmotorarticle.html

peejay

Probably best to leave the engine block alone, then. You've got all the good stuff except for the carb... a 44mm carb is way too small. A 45mm DCOE feels like a stock carb setup. Get a nice 48mm carb on it and a better intake manifold, or a Racing Beat Holley setup. (Not a RB manifold with a generic Holley, get the whole setup, it's worth it!)

jaidedeye

i already have a racing beat manifold on the car

peejay

You have the sidedraft manifold. It's not as good for power as the Holley manifold. Much longer, mugh tighter, and there's that big cork bolted to the end of it (44mm carb).

jaidedeye

gotcha....


well after alot of consideration ive decided to boost the stock 12a.