hi
i have a all stock 85 gs 12a the only thing i have done is
replaced the cat with a striaght pipe. and added a K&N filter,
and placed the air filter cover with one from rx7.com to allow more air flow. but thats about it.
i'm wondering what i could do to add some more needed HP.
please pass on your ideas
thanks

 

Do a search and see...The Forum has very recently gone over which is the best bang for the buck..

12A-N/A
12A-Turbo
13B-N/A
13B-Turbo
20B
V8's (Just Kidding)

And countless others variations. The tried and true is expanding the breathing capacity of a Rotary. Whether it be porting, headers or forced induction, they all do the same thing, getting air and fuel more efficiently in and out of the engine.

Good Luck.

 

http://mrmazda.members.atlantic.net/...t.html#NOSTART

 

You've already modified it. So its already not a stock 12a. A header is better then a just a straight pipe. But if you go with a header, you really should go with a aftermarket intake such as holley, weber, or what not to get more out of the header.

 

I've got the RB street port exhaust system--very nice, but wacky is right, I need to do some mods to my intake because i'm not using the full potential of my exhaust system...

 

I would suggest;

1. modified Nikki if you are hap
py to be aiming at 150bhp. a Holley may give you marginally more but much more costly;

2. good header to match your exhaust sysem, necessary as the stock runs out of puff at about 135bhp, remember to look at your fuel filter;

3. possibly improve the ignition with a MSD system

4. upgrade the fuel pump and add a regulator.

5. make a cold air ducting ststem from besides thwe radiator to the air
box.

Visit Paul Yaws website, its on the Forum list above, for an overview.

Search this forum, box down below, for any specific point you are considering. Its a bit of a task going through the numerous threads but there are some very good ideas.