Injector upgrade

**dethinboots** · 06-13-2016, 08:51 AM

This honestly just popped in my head, so I started to do a little reading. Apparently the stock Ls2 33lb injectors are only rated for below 500hp to the flywheel. How true is this? Also. if this is the case what is the next step? I have the trickflow 550hp top end kit going on in a little so this would put me in the replacement range. ive seen that there are multiple brands and lengths to choose from. I need to know what would be an optimal replacement for less than an arm and a leg. will using underpowered injectors be harmful? Oh! And how do you depressurize the fuel rail?

***SMWS6TA*** · 06-13-2016, 09:13 AM

Depressurize the rail but wrapping a rag around the schrader valve and press on it.

When I was shopping for my injectors for the 2nd time I went with LS3 injectors. With our pumps pushing 56-60 psi at the rail it makes those injectors 44lbs.

When I asked the guy blue printing my build he assured me that size would be plenty enough for my 403 and N20 if I wanted to later on install it.

I picked my used injectors off ebay for $150 from a G8 GT owner. I spent another $160 getting them flow tested and if needed rebuilt (didn't need to). Still came out ahead of new injectors.

Yes using under powered injectors can lead to engine damage.

A good tuner can regulate a slightly higher injector but not if it's too high, you'll flood the cylinder.

**dethinboots** · 06-13-2016, 09:31 AM

so what I'm doing in the near future will most certainly need to be paired with new injectors? will ls3 injectors fit in the ls2? I really hope I can go with the options you listed because a set of new ones is way more than I want to pay if it can be avoided. How risky is it to just plug and play used injectors? I don't have any idea where I could get them flow tested and repaired.

***SMWS6TA*** · 06-13-2016, 09:55 AM

I did a little digging, You'll need a spacer too to work on a LS2 intake. You'll also need an adapter to go from EV6 (LS3) to EV1 (LS1) for the wire harness. They are cheap I believe I paid less than $25 for all 8 needed.

I had mine tested at a boat repair facility. There are some places online you can ship too but they ran around $30-$40 per injector.

One other option is to find Ford "Green Top" injectors. They are EV1 style and same height as the LS1/2 injectors so no adapters needed. Be careful there are a lot of fake brands clamming to be green tops. I'll have to dig in my files to look for the correct part number.

***SMWS6TA*** · 06-13-2016, 10:49 AM

Look this up EBAY 281261347779

These are 47lb injectors for LS2, supposedly a direct fit.

***SMWS6TA*** · 06-13-2016, 10:55 AM

Here is a useful tool

Flow Calculator

**98TransAmWs-6** · 06-13-2016, 03:18 PM

ls3 injectors won't fit without spacers I'd just go with higher flow ls2 injectors if it were me or get a rail spacer and go with ls1 injectors but a higher flow. Unless you really want ls3 injectors then go with deatschwerks they are hands down the best I have seen for the price definitely worth it. They come with a 3 year warranty too lol. The only reason I went ls3 injectors is because I have a ls3 fast so they fit the best without modification for a cleaner look.

**dethinboots** · 06-13-2016, 06:29 PM

So are higher flow injectors a must for my future upgrades?

**98TransAmWs-6** · 06-13-2016, 07:50 PM

According the flow calculator you'd be fine. If it were me I'd go up to 42# for some breathing room since 33# at that HP level is what it calls for at a 90% duty cycle. But you could always just wait and see at your dyno session to see if they are needed.

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***SMWS6TA*** · 06-14-2016, 08:19 AM

Originally Posted by 98TransAmWs-6

According the flow calculator you'd be fine. If it were me I'd go up to 42# for some breathing room since 33# at that HP level is what it calls for at a 90% duty cycle. But you could always just wait and see at your dyno session to see if they are needed.

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^this...