[BryanT2016]

Probably asked before but i cant find anything. Is it feasable or actually capable to run lt4 injectors on a lt1 pump with the aftermarket cams with 30% + fuel lobes? I do plan on doing the low side lt4 pump.

[KingLT1]

Need both the pump and injectors so you can run the correct rail pressure to fully utilize the injectors.

[BryanT2016]

Originally Posted by KingLT1

Need both the pump and injectors so you can run the correct rail pressure to fully utilize the injectors.

Ty sir, i guess ill do the low side only for now, if my build runs out of injectors ill have to upgrade then. Dont have the extra 1800$ right this second.

[GreyGhost702]

Originally Posted by BryanT2016

Ty sir, i guess ill do the low side only for now, if my build runs out of injectors ill have to upgrade then. Dont have the extra 1800$ right this second.

It's like $760 for a LT4 HPFP, $200 for LT4 High-side Fuel Lines, and I think it's like $15 for the .060" lash cap. What's the extra $800 for?

[truth411]

Originally Posted by GreyGhost702

It's like $760 for a LT4 HPFP, $200 for LT4 High-side Fuel Lines, and I think it's like $15 for the .060" lash cap. What's the extra $800 for?

Where are you getting your prices from?

It's like $1100 for the LT4 HPFP and $560 for the LT4 Injectors.

[Sillysspeed]

Rock auto had them cheeeeeaaaaap a while back. Dont know about now

[GreyGhost702]

Originally Posted by truth411

Where are you getting your prices from?

It's like $1100 for the LT4 HPFP and $560 for the LT4 Injectors.

760 for LT4 pump on rock auto, +tax/shipping. $480 I think for injectors.

OP price statement must be the full boat including injectors. Though everything from rock auto and Michigan Motorsports would be $~1560 or so.

[tortilla-flats]

I noticed on ebay, there are now part numbered kits for upgrading an LT1 with the LT4 high side stuff. Pump, injectors and fuel lines. $2k

[ThePeoplesCamaro]

Question. I’m high jacking I apologize. I know the 2018 SS pump is the LT4 pump. Is it also the injectors? Or would injectors and rails need to be upgraded still for a 2018 to add boost

[KingLT1]

Originally Posted by ThePeoplesCamaro

Question. I’m high jacking I apologize. I know the 2018 SS pump is the LT4 pump. Is it also the injectors? Or would injectors and rails need to be upgraded still for a 2018 to add boost

No it's not. 2018 SS has all LT1 fueling.

[ThePeoplesCamaro]

1 from. 2018 Ss. 1 from a 2019 SS.

[arpad_m]

King is correct, the 2018 SS came from the factory with LT1 fueling (injectors, HPFP, LPFP). Some later model years of the SS received the LT4 low side fuel pump, but the high side remained LT1 all the way to the end. I would upgrade all three if I wanted to add boost (in fact I did, thanks to Jannetty Racing).

That said, part numbers evolve over time even when the content remains the same (say, when GM changes suppliers), and the above info only applies to stock, someone may have upgraded the high side on the powertrain you purchased.

[ThePeoplesCamaro]

Awesome sooo regardless of how it got there that does appear to be the LT4 pump (the one that’s bigger and has bolts through it). Is there an easy place to get part numbers for the injectors and rails. I know at least the rails from the donor are also different than my 2019

[GreyGhost702]

Originally Posted by ThePeoplesCamaro

Awesome sooo regardless of how it got there that does appear to be the LT4 pump (the one that’s bigger and has bolts through it). Is there an easy place to get part numbers for the injectors and rails. I know at least the rails from the donor are also different than my 2019

To my understanding the LT1 fuel rails and LT4 are identical. If you were to order rails for a ZL1 the part number would be the same as what you would get if you ordered for a SS or LT1. What you need is the piping between the HPFP and Rails, as well as the feed line from the low side connection to HPFP (the LT4 version removes the flex connection, that flex downgrades flow capacity due to the restriction of the flex.) It's also said, once those pipes see air it's required to replace them. I take it with a grain of salt. If they're allowed to sit exposed to atmosphere for an extended period, then potentially moisture/rust could occur. There are plenty of acceptable ways to protect the pipes while removed from the vehicle for a build/service rather than burning $200 every time you take them apart. As long as you followed proper torque every time they're put together, you won't damage the connections or maul the threads, so there's really no excuse for leaks either. I would say if they've been pulled apart and put back together 4 or 5 times, maybe it'd be worth throwing a new set in at that point. Then again if you're pulling HP Fuel lines apart 4 or 5 times, perhaps $200 is dust in the wind

As for the last part of your question, just get on RockAuto and lookup virtually any year 6gen ZL1 and order HPFP/Line/Injectors and when you order injectors, just make sure they are a matching set (Don't mix nominal flow with high flow/low flow) I don't exactly remember the difference between those 3 injector types, but there isn't a difference in performance, it'll just be impossible to tune a mixed set. Again I don't remember the whole story behind the LT4 injectors but there are a mess of part numbers for them and that particular injector is used on multiple platforms other than the LT4 which is why the "low flow/nominal/high flow" exists. As for the HPFP, as long as you aren't running an upgraded fuel lobe it's a direct swap, though depending on what intake manifold you run there are clearance issues to consider. I don't think the LT1 manifold has issues but the LT2 certainly does. If you run an upgraded fuel lobe (such as a +32% lobe) you'll need a lash cap to shim it. Last, the fuel lines are 3 parts so you'll need 1 of each and it's important to upgrade to the matching LT4 set because the diameter and flow capacity is smaller on the LT1 hardware, the LT1 stuff will work but you'll end up coming up short on capacity if you're really pushing the high end.