What are the rules that apply to when and where you should upgrade your injectors?

If you are running NA with stock 1991 Acura / HOnda injectors, what are the maximum HP limits that can be achieved?

If I upgrade to a higher flow injector what are the overall effects of doing so???

 

From Hondata:

Approximate injector sizing for a boosted B16A

Target Flywheel HP --- Injectors needed at 40psi fuel pressure

170 --- 240 (stock)
280 --- 440
350 --- 550
460 --- 720

first column is HP, second is injector size.


edit: made it look nicer. wtf, is up with one post trial teken?


[Modified by 2K_TEG, 1:08 AM 8/9/2002]

 

The engine is a B18A1, what is maximum HP achievable for this stock injector? Also, if I upgrade to a larger flowing injector is there anything I need to know about them?

ie. If the factory ones flow 190 cc's and the new ones I purchase are 260 cc just as an example. Will there be any down side to this? Any extra saturation or overally rich A/F I need to be concerned about?

 

i think that user name belongs to someone else...?

but anyways, here are some answers.

you should upgrade your injectors when they are not able to flow enough fuel at before maximum duty cycle. this will lead to leaner mixtures at the top end. and possibly detonation.

also if you are getting a Code 1 it would be a sign.

max HP on stock 240cc depends on fuel pressure at stock FP(40psi) 240cc would flow enough for 160HP using calculations. (assuming 55% BSFC)

the answer to what are the HP maximums - it is not 160hp, it is more.

upgrading injectors to a larger size will create a richer mixture as the ECU changes the PW of the injector to increase the fueling.

but if it is a bigger injector - the ECU opens it the same as it would for a smaller one, making it richer across the board.

which would be good if you had a bigger capacity engine.

but i cant really answer this as well as some here would,

but most would consider a internet search would be good to find this sort of info...

t..

 

 

I emailed you two adobe acrobat files I scanned out of my AEM manual. I hope it will help you. If you can host them for everyone that is great...I can't. I do not know how much power your stock 190 cc injectors are capable of.

Increasing injector size without changing engine management will result in a richer condition until the car simply does not start anymore. You should be able to increase power by 15-20% before you have to upgrade injectors. Hope that helps, the pdf files should be of more use though.

 

Just so I am completely clear on this matter. If the factory injectors are 240 cc and I move up to say 300 ish or what ever. This would be like a small straw 240 mm wide, now I get say a bigger 300 ish straw, the flow will be larger at all times meaning at idel?

 

no, the size of hte hole depends on ECU signals that tell hte straw what size to be...

t..

 

wrong.

the size of the hole remains the same, it is how long the ECU tells the hole to be open for.

so yes, the flow would be larger at all times.

unless the ECU reads O2 signals and shortens the pulse width...

t..

 

it really depends on your engine management. Will you have any, or are you just talking about taking out the old injectors and putting in new larger ones with everything else constant.

If the latter is true, then yes...the larger injectors will put more fuel in each cylinder across the RPM range. If you go with an injector too big, the car simply won't run. Think of drinking thru a cocktail straw (stock). Now use a drinking straw...doable. Now try to drink thru a short garden hose...tough but doable. Now try a fire hose...no way.

 

That was a great reply guys.

Thank You