New Injectors

[MYYellowTY]

Ive had a problem with one of my old stock injectors stuck open and killing my engine.So I picked up a set of Lucas 42.5# injectors for $100 and put them in.Well my system holds its fuel pressure again now when I turn it off.But I pulled the ECM fuses to reset it, and Im getting the Check Engine light every once in a while.Its a DTC #45(O2 rich for more than 1 minute).I turned my FP way down but my gauge hose split so I cant get it adjusted right now, but ive unscrewed the AFPR about all the way out.I have an Ultimate V.7 with a 3bar map sensor also.Will these injectors work ok with a stock injector chip?And I read it takes a few hundred miles for the ECM to adjust to the change in inj.'s.Is this true? Will the chip work? Ill try turning down the FP more and make a DM run and post it.Thanks!!!

 

[SBNova]

Re: New Injectors

I doubt you will get a stock injector chip to run that size injector. You increased their size by rougly 25%. Turning your fuel pressure down too much is going to make your low speed operation suffer too. Injectors need pressure to have a good spray pattern.

 

[JSM]

Re: New Injectors

Yep, #42 lb injectors have not had much use in syty. No really good chips out there for them. You could get them to work, but it would require some custom tuning on your end.

I suspect the $200 you saved on cost of injectors (assuming you bought them since they were cheap), is going to cost you a lot more $$ and hassle in the long run.

 

[MYYellowTY]

Re: New Injectors

What about running 38# or 36# lucas injectors?Or would having the chip setup for 50# inj. and increase the pressure on the 42.5# inj.'s?

 

[It's just a six]

Re: New Injectors

What about running 38# or 36# lucas injectors?Or would having the chip setup for 50# inj. and increase the pressure on the 42.5# inj.'s?

I have talked with Brian Green a long time ago.
He stated that he had customers of his & Todds ultimate run the Factory Ford dark blue top 36 lb injectors & ran perfectly fine w/no tunning needed.

Also,, I asked the same question here about the 36 lb injectors & there are a few guys here that has ran them & ran perfect,w/the ultimate chip set for stock injectors.

 

[dgoodhue]

Re: New Injectors

36# injectors are ~12% larger than the stockers, the ECM probably has enough adjustability to adjust for them, if they have a similiar fueling curve.

One thing I learned in changing injectors is they are not all linear or do they follow the same fueling curves. I tried to mathematically calculate what my 50# injectors would need and adjusted my 32# 'injector constant' accordingly. I did 64% of my 32# injector table, I figure it would be close enough. I couldn't get the engine to start, I end up at 80% (ie what I would have need for 32# to 40# injectors). It then ran like crap at other RPM's. I need to complete redo everything on my engine map. It wasn't as easy as plug and play.

BTW The Ford 36# have been discontinued for a long time.

 

[turbodig]

Re: New Injectors

36# injectors are ~12% larger than the stockers, the ECM probably has enough adjustability to adjust for them, if they have a similiar fueling curve.

One thing I learned in changing injectors is they are not all linear or do they follow the same fueling curves. I tried to mathematically calculate what my 50# injectors would need and adjusted my 32# 'injector constant' accordingly. I did 64% of my 32# injector table, I figure it would be close enough. I couldn't get the engine to start, I end up at 80% (ie what I would have need for 32# to 40# injectors). It then ran like crap at other RPM's. I need to complete redo everything on my engine map. It wasn't as easy as plug and play.
.

There is much wisdom in this post. Anyone thinking they can change injectors or run injectors on a chip that was programmed for injectors of a similar size is fooling themselves. It's pure luck if it works.

50# injectors from 2 different manufacturers won't work with the same 50# chip. (Or at least, they won't work well)

 

[It's just a six]

Re: New Injectors

There is much wisdom in this post. Anyone thinking they can change injectors or run injectors on a chip that was programmed for injectors of a similar size is fooling themselves. It's pure luck if it works.

50# injectors from 2 different manufacturers won't work with the same 50# chip. (Or at least, they won't work well)

Sounds correct for the most part,,,, but ask the guys here ,if they chime in?
How well the 36 lb Ford bluetop injectors work?
Everyone I have emailed to, all said they work just like the stockers.

Also Brian Green told me they are very linear injectors. Same as stock injectors.
Yes they are discontinued but there are a lot of them out there & were a popular mod for the Buick GN's @ one time. So, Buick GN guys are always selling them after they have upgraded even bigger injectors.