So I've had my rx7 for 2weeks now. I need both help and ideas are welcome. My 12A is in need of a tune up. I need to know what exactly on the internals should I be looking for for wear and such. Also my gas gauge doesn't work at all =/. I put gas in whenever I take it out just to be safe. The previous owner kept it in fair condition considering it was old age and in the middle of restoration when I bought it. I'm not so much worried on exterior or interior at the moment but I want performance. I'm looking for a safe way to get my carb'd 12a anywhere from 150-220hp but due to the mileage (164K) I was thinking about swapping it out for a 13B but i hear when you add performance they pretty much suck on gas. But as far as the 12a goes the gas gauge, I cant really floor it, it'll do this thing where it'll stop giving power then jerk back and forth for a little bit so I've been cruising around. Any wise words would be appreciated. =)

 

220 hp on a 12a is gonna be tricky without mega-money.

 

Start at the gas tank and work forward. If the car was sitting for any length of time then the fuel pick up screen (in the tank) is most likely clogged. Then check to see if it's getting the proper fuel pressure from the pump (3.5 to 4.7 psi I believe) make sure all the soft fuel lines under the car are good and the hard lines are clear (I'm a big fan of compressed air for this) I had had the same issue your having, I started at the carb and made more problems in the long run.

Leks

 

check for vacuum leaks, and check the fuel tank for rust and the inline pickup filter inside the tank as well as the external fuel filter underneath the driver side.

your fuel bowls should be about a half way full at all times,(the glass windows on the front and back of the carburetor) check them while holing the throttle open to about 3K for 20 seconds, they shouldn't drain, they should stay half full. if they arent you have a fuel problem,

if it just shutters or hesitates when you get on the gas its more likely vacuum or something else leaking. or maybe good luck and post your findings

 

Sounds like a fuel pump issue to me. Or a clog somewhere in the fuel system.

 

So its the fuel?? I want to say thank you guys for the feedback. I changed out my spark plugs today this morning. It actually lets me go through the rpm but the car still did the jerking thing as i went into 4th and then the car shut off on me in i controlled it into a lot. I have two fuel filters from walmart but it doesn't look like it'l fit, the one in the engine i have changed out. I havent gotten to the fuel system yet due to the fact of my lack of tools. My car people have the tools and such but i'd have to go there which isnt an issue. I never messed with a fuel system. but i really want to get the car acting right w/o me worrying.

 

I would check out the gas tank as stated earlier. Could be crud in there.

 

this! (although i don't know about the 4.7 PSI thing. i've never had a Nikki tolerate more than 4.0 PSI)

just go through the whole system starting with the tank. check the wiring for the gauge, but if the car was sitting outside (or in the wrong indoor environment) for any length of time, then the float may be the source of your gauge issue.

 

well it was out for a while i just got to get a jack but i'll keep you guys updated =). any suggestions on mods for the classic 12A? no bridgeporting though. And about how much would it cost on street porting and can some one explain the whole "porting" iv'e heard the terms before just never really understood it you know.

 

FIRST check if you have fuel or not, trust me these cars wont run very nicley on a gallon of gas or so alone. if you do check the fuel tank for rust.
easy way to check without needing any tools, look into the neck of the fuel tank with a light and see if it looks okay inside. wont show much but it will be a good indicator if you should drop the tank of not,
secondly check the fuel bowls. sounds like there not staying full but theres an easy way to confirm this.

start the car, open the hood, use your right hand (or a friend) to open the throttle to about 3k and hold it there for 30 seconds or so, and watch the front bowl, see if its staying half full.

:note its probably a fuel problem because ive experienced the same thing except i was on the inspection rack and the car nearly fell off, and died. due to the jerking and it was the fuel filter, clogged thus i realized the the tank was full of ****.

 

I never leave w/o puting at least 10$ worth f gas if i suspect its low i wont drive it at all lol and the front bowl did stay half but i have yet to change the bottom fuel filter due to i have two different sizes i brought the walmart brand but they have this weird screw in style rather than the hose tubed kind

 

I pulled that range out of the FSM, however if you have some personal experience with a nikki not handling anything over 4 psi, you may have solved another one of MY problems! What range have you had the best results with?

Leks

 

mines is at 2.5.... and ive been told that is normal. bowls stay full, great pickup no problems

 

So to keep you guys updated. I switched out the bottom fuel filter in my gfs garage the filter was really bad it was like a liquid rust i did a test run and the car moves very decently now. i still have to check the fuel system for the gauge. Other questions ive had what is the stock suspension set up on the 1st gen just curious and can the gauge cluster be switched out? Also (srry for so many questions) i have a stock carb right now I know i need a new intake filter. is there anything i can do to the stock carb to get a lil more power, I might say for only 100hp that the 12a gives out or advertises it really does move. What do you guys think of the 12A

 

i would say most cars due to age would be very lucky to have 100hp lol my car is at 140k on the clock right now and i haven't had the heart to dyno or compression test it. but it runs great.

 

LOL mine is at 164K. and it doesnt feel like 100hp to me

 

Glad I read this thread. I got mine a few weeks ago and drove it for the 1st time this week and it does the exact same thing. I've got it and jack stands now so it will be easy to check on these potential issues. Thanks!

 

Let me know how that goes

 

`im having the exact opposite problems u guys are im geting to mmuch gas at idle my floats are bead i think or bad jets idk yet just super hi hydrocarbons at idle and im fine at cruzing speed

 

look down the carb see if the secondaries are dripping. they might be and causing excessive fuel at idle.