[Need4Camaro]

2017 2SS

It appears there are several different part numbers for our fuel injectors even for similar models and years (Even the SS from a 2017 has multiple different PN's vs a SS and ZL1)

It seems like the only reliable way to get the correct injector is removing the old one and examining the PN from it.

Questions:
1. Why did GM do this?

2. Are the PN's interchangable between similar years and models or is it absolutely necessary to get the correct PN?

3. How much power do stock injectors support?

4. Can they support F.I.?

5. Are aftermarket injectors available for our cars and when do you start looking into them?

6. Do after market injectors support our cold start duty cycle? (dumps a ton a fuel and very loud cold start)

[bishopts]

1: GM will build a car using the cheapest parts that will do what needs to be done. That's where engineers and bean counters have conflicts.

2: part numbers change for lots of reasons, some being they found cheaper ones that do the same thing. Some being changes were needed.

3:enough

4:yes

5:yes, when your stock ones cant keep up

6:injectors don't have an affect on cold start cycles.

A fuel injector is a solenoid that acts as a controllable gate. When it is commaned open it lets fuel pass, when the command stops fuel flow stops. It has a specified flow rate that changes depending on how far it opens, the holes that fuel comes out of, the path the fuel flows in. Your injection cycle is a duty cycle control setup. Each time its needed the computer will send a series of on commands within a specific time frame. Its a pulse width modulated signal.
So for example you have 500psi in the rail and you commanded an injector on for one second at a 50 percent duty cycle. Then it will be on and off 50 percent of that second. And flow fuel related to that time/duty cycle. If you needed more fuel that what the rate allows, you increase the on time(which is how long the gate is open). Change it to 60 percent duty cycle and it is open longer letting more fuel to pass. Eventually you will come to a road where no matter how much you leave it open you can't get enough fuel to feed the need for the engine. Thats when you need a bigger gate that flows more fuel per second. (Bigger injectors)
So now you have bigger injectors, the duty cycle that you had before doesn't match anymore. 50 percent duty cycle will dump much more fuel than it did before. So now you have to go retune just to get the car to run normal.

[Need4Camaro]

Reason Im asking is because my stock injectors keep failing and leaving me with random misfires. I replace and it works for awhile then another one fails. I was wondering if going aftermarket would be a better idea than going back with stock injectors.

Currently Im at about 500 RWHP and running E85.

So far Ive replaced:

Injector #4 (about a year and a half ago)

Injector #5 & 6 together and it worked for awhile

Now both 5 & 6 need to be replaced again so Im thinking of just nuking them.

[Joshinator99]

Originally Posted by Need4Camaro

Reason Im asking is because my stock injectors keep failing and leaving me with random misfires. I replace and it works for awhile then another one fails. I was wondering if going aftermarket would be a better idea than going back with stock injectors.

Currently Im at about 500 RWHP and running E85.

If you’re going forced induction I’d go LT4 injectors and HPFP *AT A MINIMUM* since LT1 injectors are virtually useless with a blower. Sounds like a good time to upgrade.

[bishopts]

Try running 93 more often. It lubricates better.

[Need4Camaro]

Originally Posted by Joshinator99

If you’re going forced induction I’d go LT4 injectors and HPFP *AT A MINIMUM* since LT1 injectors are virtually useless with a blower. Sounds like a good time to upgrade.

Is it a bad idea to upgrade before the blower install?

[Joshinator99]

Originally Posted by Need4Camaro

Is it a bad idea to upgrade before the blower install?

It’s easy to do when you put the blower on, since you have to take the intake manifold off to do the Whipple or Maggie anyway. If you’re going to do a centrifugal blower then I suppose you could do the injectors anytime. But yeah, do them now if you want. You’ll just need your tune adjusted when you do since the LT4 stuff runs at higher pressure and has different flow rates vs LT1.

[Joshinator99]

Originally Posted by bishopts

Try running 93 more often. It lubricates better.

93 is trash on a high compression boosted motor FYI

[Need4Camaro]

Originally Posted by Joshinator99

It’s easy to do when you put the blower on, since you have to take the intake manifold off to do the Whipple or Maggie anyway. If you’re going to do a centrifugal blower then I suppose you could do the injectors anytime. But yeah, do them now if you want. You’ll just need your tune adjusted when you do since the LT4 stuff runs at higher pressure and has different flow rates vs LT1.

We're ganna veer off topic for a moment but would you supercharge a LT1 SS or would you keep it heads / cam NA and buy a ZL1 for your supercharge needs?

I have a magnacharged 99 Z28 but I wonder if I should do the same to my SS or if Im ganna keep my SS NA.

[bishopts]

Originally Posted by Joshinator99

93 is trash on a high compression boosted motor FYI

Crapped out injectors from lack of lubrication is pretty trash too. But i guess i don't really care if I'm ready for the next light to light street race. I go more for the make it back home with no problems.

[Joshinator99]

Originally Posted by Need4Camaro

We're ganna veer off topic for a moment but would you supercharge a LT1 SS or would you keep it heads / cam NA and buy a ZL1 for your supercharge needs?

I have a magnacharged 99 Z28 but I wonder if I should do the same to my SS or if Im ganna keep my SS NA.

So it depends. If you want quick/easy/warranty boosted car then buy a ZL1. If you’re ok doing it in stages then an SS is the way to go. I had no idea I was going go this crazy lmao! I started with an SS and every year I just play around with it a little more. But either option is great. Buying a ZL1 is a nice shortcut that jumps you up the ladder very quickly. There is no wrong answer though. You asked my personal opinion: I’m not a fan of big cam NA setups since I don’t like the drivability. Given that I never drive on the street anymore you’d think I would not care lol. So, give me boost everyday of the week.

Originally Posted by bishopts

Crapped out injectors from lack of lubrication is pretty trash too. But i guess i don't really care if I'm ready for the next light to light street race. I go more for the make it back home with no problems.

I’ve been E85 since 2019 with no injector issues FWIW. But nothing wrong with reliability so I understand where you’re coming from. But if you want to play in the boosted world, E is where it’s at.

[OB0001]

A few oz of Marvels mystery oil will keep the injectors and fuel pump lubed 4oz per tank of E85 dose the trick.

[Need4Camaro]

I don't think its the E85. I've been running it for about 3 years now but these misfires just started and gradually progressed a few months ago. Originally it only happened during that loud cold start period but ran normally after warming up so I ignored it, but it's gotten worse. I replaced the injectors with some used injectors lying around at the shop I use to test it, and it got worse instead of better.

I'm going to grab new injectors and see what happens.