13b series 4 engine non turbo questions?
 

Hi there guys/gals,
im glen from Australia and new member here.
I recently just brought a complete running 13b series 4 non turbo 6 port engine for $800 aus!
came with 3 month warranty.

now im finding out that this series 4 13b 1988 non turbo engine is not very good to build with !?

some rotary shops here in oz are saying im waisting my time with this engine ?

why is is this ?
im hoping this statement could be wrong!

my plan was to add a 48 mm ida weber,a good flow exhaust,bridgeport it and lighten,balance and blue print it!

is there anything that can be done to modify and make this engine into some thing good?

do any of you guys have on here good experience and results with this engine please ?
what sort of power can be made out of this engine please ?

I want to keep this engine non turbo!

also I have heard guys saying before you can add two stroke pre mix oil in with your fuel to help lubricate and protect the engine better ?

would luv to here your thoughts on this pls!
kind regards
glen

well,can any one pls help advise me ?! :O

Dude, it was midnight here when you posted. Have patience. Someone will probably come
along today and answer you.

Here are the Manuals good luck..

My understanding is the issue stems from the extra secondary intake ports. In stock form they are actuated; closed at low engine speeds and open at higher speeds. The S4 engines use exhaust pressure whereas the S5 engines use the air pump to actuate rotating valves to open the ports. My understanding is potential is limited because the ports are too big to be left open all the time and too small to be left closed. There are isn't much metal remaining between the ports and coolant passages so you can do only so much with standard porting. If you leave the auxiliary ports open at all times and combine that with a bridge port I imagine you'll end up with an engine with a very "peaky" power band.

Most people going for the most power in a naturally aspirated configuration, myself included, start with turbo motors.

Incorrect.

HERE are the manuals.
http://foxed.ca/index.php?page=rx7manual

lol

thanks guys for your reply and imput!
I heard that peripheral port could be the go to build my series 4 6 port ?
regards
glen

P-Ports will give you the most hp without a doubt, but that opens up a different can of worms regarding apex seals, and clearances. P-ports love to rev so now you're looking at machining the rotors and building the rotating assemble to the highest of standards.

regarding the pre-mix, yes. Always a good idea with these engines