Injector Selection for use with HP Tuners

[slayercft]

Hello, My name is carl, I'm looking for injectors for my ls build. I've recently purchased Bosch 0280158051 / GM 12576341 42LB injectors because I was aware of the availability of data for use with hptuners (which I have just purchased) These would not fit properly/seamed to be finicky and using adapters didn't suite my needs. Will post the information about my truck off the top of my head.

2005 Silverado 1500 2wd crew cab
stock 5.3 was bored to 5.7
flat top pistons
224 lift comp cams
obx long tube headers
tb spacer
msd plugs/wires
k&n intake
243 no heads
Machine shop (very reputable in Houston) that did the rotating assembly gave me a 410hp crank build. Its probably close to 450.

So far from stickys and google research ^^ It seems that 8x injectors at 410hp at the crank is only about 29lb/hr...the stock injectors are 27 lb/hr if I remember correctly. I need something that would work with hptuners and have information (flow tables?)readily available. It looks like the 8.1l marine injectors at 42lb hr would be a good fit, however I'm leery from others mentioning that they are harder to tune for a newbie like me. Does anyone have any good advice or quality brands that I should be able to use for this? Thank you to all in advance! Carl.

[Eaglegoat]

Using an adapter kit like from FIC (connection) and the injectors you already have is going to, IMO, be your best bet. The data is readily available and easily converted, it's an oem next-door and very reliable, and as you already know they will more than support your needs. I've never had a problem with that injector, or the FIC kit if it was needed.

[slayercft]

I've actually returned those injectors (I bought them with adapters and they were pretty bad quality, I had to compress them with a vice to fit) I'm wonding if there is much information on the 8.1l marine injectors from GM, they are about 1/2 the price and would just fit in with none of these cheapy adapters and requining me to refit all the electrical connections (I can do It, its just between the injector adapters and the painless kit for the electrical connections it seems like a lot of work and modifications and money for the same thing : /) I've A couple of sellers have emailed me with injector information on the 8.1L but nothing of much use. Do you think my best bet would be to order those same injectors again from a different seller, order the FIC adapters and change my mini Delphi electrical connections to the ev14? To me it seems like this is a lot of work and money and I'm not exactly sure why I'm doing it!

[Eaglegoat]

I haven't used the marine injectors personally. I'm not sure where you could get the proper information on them. If you can find it it should be plug and play with your PCM. If not I can help convert it.

The FIC kit has the proper plug adapters with it no need to do anything except plug them in. They have a good quality top spacer in the kit and maybe me orings (I can't remember). Their website can be a little confusing sometime. If you call them just stick to a GM oem injector, don't let them talk you into anything resized.

There are a limited number of options for direct replacement on the older trucks. Once GM went to ls3/7/9 style on everything it got easy easier.

[mowton]

I actually had a client that us^​ed the Marine 8.1 injectors, was a 2002 auto Thoe 5.3l. I was a bit concerned at first but developed data from a card he received and they seemed to work ok. Idled good and had good driveability. Obviously not my first choice........

Ed M

[2xLS1]

Your stock injectors are 24#. Find a set of 02-07 classic flex fuel injectors. They are 33# and will be adequate enough for what you are building and have readily available data. And our HP #s are very optimistic. I doubt you will be anywhere close to 450 at the crank especially since I don't see any mention of heads.

[slayercft]

I want to thank you all for the information and options/opnions! I decided to go with the stock bosch/GM injectors that will fit right in with my fuel rail (a rep from FIC had some) with the information on them for use with hptuners. I will definatly take a look at the marine 8.1, as I have access to a set for $100 and figured its worth giving it a shot. Actually I have a 05 suburban with 5.3 flex fuel, I should have just swapped those injectors, if those are the ones you were talkinga bout @2xLS1 ^^.

[2xLS1]

Yes you could swap them and disable the flex fuel option on the 05 Suburban. They are only needed if you are going to run E85. You would have to change the tune for the Suburban which would mean you would have to license the PCM at a cost of 2 credits or $100.