Ok. I did a quick search and couldn't narrow it down enough to answer my question:

Why do people substitute in a 454 90lb injector into their throttle body as opposed to just upping the PSI of the stock injector?

(presuming that you have an upgraded fuel pump and fpr)

Sorry in advance if this is a rookie question...

 

The stock injectors go static "max out" when used on heads and cammed motors. They cannot supply the fuel flow needed.

 

So they can say they're using big block parts on their small blocks

Seriously, increasing fuel pressure on a lower flow rated injector will only take you so far.

FP increases on a higher rated injector increase fuel flow rate exponentially compared to a lower rated injector.

Clear as mud?

 

Sort of makes sense. Do you think I could raise the PSI on stock 55# injectors enough to make 300-320HP maximum? (Assuming I burnt a chip to match).

I can honestly say, at this point 300HP, 350lbft tq is a good goal; I don't want to go much higher than that since this is my daily driver, and I'd like to stay in the double digits MPG on the highway AND and don't want to be breaking trannies, axles, etc.

 

no, you will need more.

I'm static with probably 230-250 HP.

 

I checked the wreckers... the guy I talked to said that he could count the number of times he's seen a 454 in the junk yard on one hand over the past 10 years - let alone a TBI 454.

Where can I find 454 injectors for CHEAP?

 

check ebay? or see if rebuilt are available on the net. i think a post was made a few weeks ago on rebuilt.

 

make sure you dont get 1995-1996 injectors. the are high pressure units with i believe a 43 lb rating at 12 lbs FP.