I was talking to a friend about EFI, and we both came across somthing we never thought about befor, if you have a turbo setup, or really good airflow system on your car, would you benifit if you installed a 5th injector befor the TB and get a controler that activates it when the TB is open all the way? Or if you installed it on the Intake manifold?

 

I'm just guessing, spraying into a cylinder is beneficial because the spark burns all the fuel....if you spray fuel in the TB....wouldn't it leave some fuel behind in the piping or the TB or something like that? Plus that sounds like it would be too much fuel.

 

similar to the zex kit that opens its jet whenever the car is at WOT, but no, i dont think an injector would benefit from spraying into the TB like the nitrous kit does.

ive seen some setups where people have two sets of 4 injectors, 4 on the top (normal) and 2nd set on the bottom, but those were extremely built and very powerful motors, i highly doubt any average joe honda owner needs more than 4 injectors, and if they do, just get aftermarket ones like RC (some are exceptions)

 

the 5th injector was an idea mainly used on the escort rs turbo (hisssss) it was an injecto mounted in the side of the top boost carrier and was conected to a boost switch+ a wot switch so when there was enuf boost at wot it would come on, the 8 injector setup was used on the 1st rs500's and rs200's (hissss) and worked in the same way but was more of an ecu controlled thing, altho if your car has the propper injectors, a decent management system and is mapped propperly there should be no need for a device such as a 5th injector

 

Some turbo kits like the old max rev one use a 5th injector before the throttle body. This is ideally cheaper but doesnt insure equal fuel to each cylinder. Adding larger injectors in place of the stock ones is much more efficient.

 

That's old school fuel management. We know better now.

 

Got ya, I was just curious, thanks for all the replys. I have seen that 5th injector on a friends Escort RS Turbo. I think I will stick to larger injectors, presure regulator, and a high output pump...