Just a thought and this is something I would like the boards cosiderable knowledge on. Why not add two injectors behind the throttle body and cause a little fuel flow to be introduced into the plenum area? This would for one thing help dilute the oiling in this and the runners and could also keep from adding larger injectors, (increase fuel for increase cubic inches) and add to the puddling which has to occur on top of the intake valve area.
Since I am newer to this area it may have been tried and if so with what results?? Les

 

Why ?

 

you must increase the fuel flow into a engine when the cubic inches are increased(a Given, larger inches more fuel) and by simply adding larger injectors in the stock location are you doing what the engine desires or would a mixture of fuel and air going thru the runners deliver a larger power increase?? It would seem that a mixture going down the runners might provide a increase in horse power and or torque thru better atomization of the fuel. Les

 

Great thinking. Your idea has already been thought of. Do a web search on EIC (extra injector controller). These are popular with turbo and s/c add ons.

 

Band-Aid

 

I don't see how it would provide better atomization of the fuel.
By the time it got to the intake ports it would be running/dripping, not spraying directly out of an injector like it is now. Or am I missing something?

 

No your not, Cause the whole point of Port Injection is that the Fuel shooting against the back of the intake valve (or close to it) Provides the best Atomization you can get.

There is really no reason to add auxilarry injectors...

 

Sounds like throwing TBI parts onto a TPI engine...heh...Wouldn't that cause the car to run rich as all get out? Or, i suppose, even if you got it stoich...Are you using stock heads ect ect? I dont know if you'd need more injectors unless you have a blower on it or something....As far as fuel atomization i gotta agree with bort

 

TPI intake is not design to be a wet intake . I could just imagine fuel puddling and then you have a time bomb waiting to go off. Plus the added fustration of tuning the cyl correctly , the wireing , how you are going to control those extra injectors , when you could just by a bigger injector . Sounds like a lot of work , and headaches , for no real gain .

 

Well, the cold-start injector sprays into the base, where it goes through the small cold-start runner into the plenum, then back down the intake runners, etc. So fuel does flow through the older TPI intakes at least. So that doesn't make it a bona fide "dry" intake, although it's still considered as such. I don't think there will be a great deal of fuel puddling, but you're right in that it's not designed to run in that fashion.

Don't let that stop you from constantly trying to come up with those ideas, though, Les.

 

Yes there is a cold start injector how many inches above the main injectors , notice i said injector . Im just trying to save someone from a real nightmare , and some money loss.
Lets look at like this , if the added injectors theory was a good idea . Than why did supercharger kits go away from that design . Im not a engineer , so the only reason i could think would be a less practical , less efficant way to add fuel . I really think you would be better of with a bigger injectors , in the oem spot .

 

True that. I don't see any legitimate reason to have a port injection setup backed by throttle body injection. The computer is made to use injectors that are placed at the port, and I'm sure there are some finite variables involved that just wouldn't work with "back-up" injectors placed behind the throttle body. A neat concept, but just unecessary. Good imagination though, Les.