I tried to search this but getting conflicting information. I am planning on getting new injectors soon.I have been looking at fiveomotorsports.com.They offer a bosch injector that is for a ford.I know I need a 22lb injector for my L98 but when you go to the other car it is a 19lb injector.I asked fiveo and they said it is because of different fuel pressure.The other pressure is lower so that is how the 19lb injector becomes 22lbs.Is there any truth to this?It really dosent make any sense to me.But I am no expert.I just dont want to get the wrong injector.Thanks for the help Dave

 

Anybody?Looking to buy new injectors ASAP. Thanks Dave

 

If you have a 350, then the best long lasting injector is the Ford Racing injectors and you want to buy the 24#/hr injectors. All of our TPI cars run 43.5 psi from the factory. However, The Ford Racing injectors are rated 39.5 psi. You can buy these injectors at Summit Racing.

Our ECMs have the range of correction which will allow us to run these 24s w/o making an EPROM change (as long as you have a 350 EPROM).

I have been running my 24#/hr Ford Racing (formally called SVT or SVO) injectors for about 10 years now!

 

Thanks doc.That brings another question.Why does everyone say to have the prom set for 24lb injectors if you dont need it?I would go with 24lbs if I dont have to mess with tuning.I still dont understand fiveomotorsports ansewer about the 19lb injectors and how they cross referanced these.

Thanks for all the help Dave

 

Sometimes you need to set a new constant for the injectors in the PROM to make in run like it should, if you get 24lbs injectors to a 305 that have 19 stock , then you got a problem, Then you need to change that in the PROM (belive me, because I have 24lbs injectors on mine) When you changed the constant the car will run good again.. The ECM need to now wich size the injectors are if you buy LARGE ones... 350 engine using 22lbs stock and 24 is only 8% larger than stock, but 25 on a 305 is 20% larger.. for example..

on a 350 it may work good with 24lbs on stock PROM.. maybe little rish sometimes but it will work..

on a 305 you NEED to change the injector constant in the PROM..

 

TheKing hit the nail on the head. The 24s are about 8 to 9% bigger than the 22s. The reason why its not a must to change the fuel injector in the EPROM is this: our ECMs are baselined at 128, if you scan your engine doing I normal drive around and you see only 128 for your BLMs, then you are running dead nuts perfect. Our ECMs can corect down to 108 and up to 158. 108/128 is a 16% correction. A BLM below 128 means that the ECM is taking fuel away, which should happen if you are close to 128 before you change the injections. However, it is best to get a new EPROM burned in order to send you back close to 128 so that now you have the full range of correction in the ECM.

50motorsports: I dont know about these guys, they are Ford guys. (I allow myself the right to criticize them because I work at Ford in Dearborn) Their advice should have been 19s for a 305 TPI and 24s for 350 TPI. However, if you install 19s and an AFPR and run the 19s at 56psi, you will get 21.7 #/hr of fuel, which is almost exactly what the EPRM is programed with,, but you are maxed out on that injector. That is why its best to go with the 24s, and allow yourself some nice bolt-ons and get the fuel you need.

 

If you set 19lbs injectors to 56psi pressure the injectors will work but they will work at an higher % because the 350 uses 22lbs (to keep down the injector pulse width) but the 19lbs will work..
It will shorten the life of them but they will work, maybe many many many years.. In the beginning they thought of putting 19lbs in the 350 to from factory but they decided after that 22lbs is better just because the injectors will work att lower inj. BPW and last longer..

So dont use 19 if building a bigger engine or using a 350.. just to keep the injectors working at a lower % and last longer.

 

Thanks guys.Iam just trying to understand where they came up with this information.Fiveomotorsports says these injectors are a direct replacement.I thougt something was funny because the 305 has the same part number also.He also says the 99to00 ls1 injectors are an upgrade injector with no tuning.It is really begining to look like he dosent know what he is talking about.