born2burnurazz

What are other options other then the expensive oem type replacement that they sell at Advance auto parts. Whats the best size to use on a 88'n/a with future plans on a intake,header,and full exhaust(no catz) Anyone heard of venom injectors? Any good? Help please I've been out of the rotary seen for about 8years and I'm lost with all the new stuff out there.

Icemark

for those minimal mods the stock 460's are more than large enough. In fact they would be fine up around 225 horsepower. That would be considerably more power than your mods would even get you close too.

You may wish to read the FAQ for FC sticky thread found at the top of this, the 2nd gen RX-7 technical section as this is covered there.

In addition, to make more power on a stock port non turbo, you actually lean out or cut back on how much fuel is being injected.

born2burnurazz

Well the reason why I ask is the stock injectors are flooding the engine. Sticking open and if I'm going to replace them I figure might as well replace them with aftermarket injectors so the fuel is available for future mods. Right now the car is a real pain to get started and then after it is started will run for about 10minutes or so and then floods out and dies.

Aaron Cake

iTrader: (1)

Have them cleaned. Most communities have many injection shops that can clean the injectors with a days turnaround. Check the phone book for "injection" and "diesel injection".

If you replace them with bigger injectors, you will need some way to control the fuel (piggy back like the S-AFC or a full standalone). It's not worth the trouble unless you KNOW you are going to need larger injectors (not likely).

born2burnurazz

From what other people have told me its that basically all Rx7's in this year range had faulty injectors and that even after having them cleaned they still leak a little bit. If this is true I'd rather just replace them with different ones just to cure the problem completely.The leaking injectors is supposedly why the 2nd gens have starting issues. However, I've heard its the cold start system to blame aswell. I'm just trying to find out whats the best solution. If I can get a new set of 550cc replacement injectors at a good cost I would do it but don't want performance to be screwed because of it. This is my first 2nd gen rx7 and I know very little about the 13b,so forgive my stupidity, but wouldn't the fuel injection system compensate for the larger injectors after reading a rich condition from the o2 sensor and reduce the injection pulse timing?

Icemark

You should stop listening to people you are listening too. They are steering you up the wrong river and really have no clue about an RX-7.

Only about 25% of the time leaking or dirty injectors cause flooding issues. Vast majority of the time it is more related to poor compression or very very very rarely to a bad ECU.

Heck I would also bet that people that don't know how to start a fuel injected vehicle also weigh in pretty high. You do know that you do not ever touch the gas pedal when starting a non flooded fuel injected vehicle.

But it is not a defective injector by any means. This same type and manufactures injectors are used on 50% of the cars from Japan in the 80's and early 90's.

And even if it was the injectors, once cleaned the injectors will not leak. Any leakage is caused by dirty injectors, not by defective design.

NO NO NO NO... the stock fuel injection system (as well as the majority of aftermarket stand alone ECUs) are/ is not sophisticated enough to control the amount of fuel to richen or lean the car out. Putting 550cc injectors (or even a bigger fuel pump) in without any sort of tuning device or controller will result in two things... neither of which you want.

#1 Gas mileage will go down.
#2 Horsepower will go down.

The stock system is simply based on maps that change the fuel based on pre-set points. If you change any item it will simply not know, and continue to run like it was the stock equippment. So if you were injecting 20cc per event, and you put bigger injectors in, now you are injecting 30cc per event in, with no increased air or flow... The ECU does not say, "oh wait I have 550 injectors in, I need to only inject 20cc in... instead it simply switchs the injector on for the 15ms that a 460cc injector needs to send out 20cc of fuel.

But go ahead and waste your money and put bigger injectors in that are not defective. Because that is what your people told you. Instead of spending less than $100 and doing it right as we have suggest here.

Of course if your compression is low (as I suspect), and you are having flooding issues from that low compression... well then 550cc injectors will only make the whole situation worse... because the last thing you need is more fuel.

born2burnurazz

Yes I know they are...thats why the statement said: "The leaking injectors is supposedly why the 2nd gens have starting issues."


As for the EFI system retuning itself a simple yes or no would have sufficed. All I needed to know was if the 2nd gen rx7's used a closed or open loop fuel injection system and that would have answered the question. As for your assumption of compression I'll check into it, if this is so who out there sells reasonable overhaul kits?