I have placed a Racing beat "High Performance" exhaust system on my 1985 Mazda RX-7 GS (12A). Later, a customly made cold air intake was installed. Now I would like to add some more performance parts but don't know where to start. I am also not very likely going to change my carb or port my engine. What other things could I add to give me more power and torque I can actually feel? Someone mentioned a new K&N air filter. Is this a good option? I also heard about a better fuel pump and ignition. What do you have to say about these? I understand that these sorts of questions get asked a lot, but I would like to know for my information. Thank you for your time.

 

The stock fuel pump could barely keep up with the stock 12A when it was new...imagine its predicament now, 18 years later...get a Mallory Comp110, choice of Champions...

 

If you are going to replace your carb in the near future don't buy a K&N filter as it won't fit your new carb

I have heard good things about upgrading the ignition system eg Direct fire set up

I don't think a new fuel pump would make your car feel faster lower in the rpm ranges ... fuel pumps usually start to show weakness at sustained high RPM or high loads ... but it would prepare you for the new carb

.... its up to you ultimately

 

woops your NOT upgrading your carb or porting ...

 

Fuel pump first!

The K&N's main benefit is that it's reusable. It costs as much as 5 or 6 paper filters, so you'd better keep it a long time. The "40 HP Benefit!" claim you see in the ad was tested on a 500+hp big block that had a very restrictive air cleaner setup that was holding everything back. So in that respect it's kinda like putting a stock Nikki on a monster bridge port, dynoing 135hp, then going to a big Weber, dynoing 335hp, and then saying "A Weber carb is worth 200hp!"

The ignition thing was hotly debated... we all eventually decided that it helps a lot if your mixtures are out of whack. (we didn't decide much else ) and the HP gain was minimal if your mixtures were halfway decent.

Fuel pump... The top #1 thing you can do to any carbed RX-7 and immediately notice the benefit. You also need a Holley regulator and a good gauge. (These are not options)

 

Exactly...

 

I've a K&N on my GSL-SE. NO HP gains the butt dyno can feel, but the engine seems a bit happier nonetheless. My idle has smoothed out and there's a minute amount of extra pep in the low end, that's about it.

Got it off eBay for $35.

 

Where can i get a good pump? Easy to replace?

How bout the regulator and gauge (where to buy that is)

 

You aren't going to feel any significant power increase out of any of those choices. Not like when you did your exhaust. The fuel pump helps a bit, but it isn't a "wow, my car is so much faster" difference. It's a fairly subtle thing. The K&N combined with an opened up aircleaner (I used to have the rx7.com one; waste of money, build your own. Also Racing Beat makes one) makes a little difference. Again though, nothing too amazing. You'll notice the sound more than anything else.

If you want substantial, noticeable power gains, that make you go "holy ****, my car is way quicker", you need a new carb (and of course a better fuel pump and regulator go along with that). Then worry about porting.

If you refuse to think about carbs, you'll pick up a bit of power from advancing the ignition a few degrees, losing all the emissions junk and unnecessary equipment, re-jetting your stock carb, removing every superfluous piece of weight you can possibly leave at home, and upgrading the fuel pump. Not to mention making sure everything is in tip top tune and all maintenance stuff is done religiously.

But really, and I'll say it again, if you want significant horsepower gains you'll need to look into a better carb (along with fuel pump). Then you can decide about ignition, electric fan, pulleys, and whatever other little stuff you want to drop cash on.

See, you get what you pay for. If you want real power increases, you have to spend money. You aren't going to make shitloads of extra power with a $30 air filter lol. You'll need to drop five or so hundred bucks for a carb/fuel pump setup to get what I think you want.

 

Take it form em i have doen the rejetting the weight stripping, removing emissions, sterlings modd to the carb, and a fuel pump and regulator. All this si due to after a while i thought my car was losing power it runs quicker but in a month i will be looking for the next llittle up. Basically i am to the piont of having to finish the sc for power. i have done the performance exhaust and put a brand new street port and the fastness just wares off. my friends ride with me and are like damn it is quick and i am like really. it is wierd the fast it gets the quicker it wares off. in 3 months i have shaved times down in the thousand foot and i am running 8.3 miles per hour faster still i think it is slower than the day i bolted the motor in.


jr