Injectors
 

I will upgrade my injector size but, what would give me more top end instead of out of the hole digs? Primary need to be bigger or Sencondary need to be bigger? I'm looking for top-end performance over low-end. Please tell me.

sencondary for top end.

depending on what ecu you are using i would go with 1000cc +

First, the lecture...
To make POWER, you need: air, fuel, spark / ignition.
Spark / ignition is a given, so we ignore that.
Now, we're left with air and fuel.
Best power is produced at around 12.5 : 1 ratio, air to fuel.
If you're already hitting this ratio, increasing fuel DOES NOT PRODUCE MORE POWER.
You just enriched you're air-fuel ratio.
Running rich kills power and fouls spark plugs.
You just made LESS power cause you're dumping too much fuel into it.

Second, you need to give us a little more information than that...
What kinda turbo? Stock?
What kinda engine?
Any mods?
Fuel computer?
Fuel upgrades?
Fuel pump?
Stock fuel injectors?
How much boost? Are you even turbo'd?
How old are you?


-Ted

im supercharged on 7 pounds running 550 primary 720 secndaries

Ok, I have a 1990 GXL/ with a J-Spec S5 Turbo II swap, it came with NGK plugs and wires, KnightSports altenator pully kit, some kinda riged up idle timing control and the remainings of a greddy boost controller...BUT ANYWAY, Its not running ATM I have to cut and resader the wires because the harness is too short for the US spec body. I was just wondering which would give me more top end instead of low end power, primary or secondary?

secondary's would. but there is no point in upgrading them really on the stock turbo.. if anything i would get some 720cc secondaries and up the boost. but your gonna need a fuel pump with a fuel upgrade

Do you have an FCD?
If you don't, bigger fuel injectors are not going to do anything for you unless you do something about the overboost fuel-cut.

Unless you're running higher than 10 - 12psi on the stock turbo, bigger fuel injectors are not going to do anything for you.



-Ted