Fuel injectors, worth upgrading?

[armysig]

Hey guys, I've been seeing that a lot of guys that upgrade their LS3/L99 Supercharged cars they take the supplied injectors and replace them with quality high end versions.

So I was wondering if replacing the injectors on the ZL-1 would either increase (slightly) HP or is it just a better and more efficiant way of providing fuel to the engine?

[radz28]

IIRC - LSA enjoys a similar dual-mode (so-to-speak) fuel system, similar to LS9 because the obvious fuel requirements of the SC. We know they're upgraded above LS3-specs', but something that seems new to 'V LSAs, is it seems, perhaps, the injectors may have been changed.

In a current article in GMHTP, ADM was adding their Stage I 'V-upgrade (along with the customer's air cleaner upgrades) and in the final tuning, Andy noted that he was expecting the injectors to reach their repsective limits, as I suppose they have on earlier V' mods', but this brand new 2012 V' didn't seem to approach the current car's limits.

The car ended up around 590 RWHP, and it seems like Andy, perhaps, though there may be unannouced '12 changes for LSA, and at least in the Caddy', it seems there's a chance that either they had a ringer for this article, or LSA-V's might be making a little more power (perhaps because ZL1 changes might carry over to V', somewhat).

Anyways - unless you are seriously increasing fuel requirements (i.e. adding a top-end kit or more boost), adding fuel may not necessarily be worth the expense, especially if you don't intend on any of the above. I guess we're just going to have to wait :(

[Speed74SS]

On the V's with an Upper Pulley and CAI the stock injectors were about maxed out. Most people who have modded their cars with both pulleys changed are swapping injectors. I had headers, CAI and a tune and my stock injectors were hitting close to 100% Duty Cycle. I am not sure if the stock injectors in the ZL1 are same or not.

I am going with the ID850 injectors as they should be good for almost anything I want to do and good for E85 also. I believe we are seeing the stock pumps good up to 650-700rwhp - past that you can run a Boost-a-pump.

[radz28]

Thanks, Speed'

I just wanted to be clear that I was only commenting on the '12 that ADM tested for GTHMP. From the article, Andy reflected exactly what Speed74SS said about the injectors max'ing out. The '12 didn't, which surprised Andy, so maybe ZL1 and CTS-V are sharing more components than GM's announced. The more the better

[DrkPhx]

Originally Posted by armysig

Hey guys, I've been seeing that a lot of guys that upgrade their LS3/L99 Supercharged cars they take the supplied injectors and replace them with quality high end versions.

So I was wondering if replacing the injectors on the ZL-1 would either increase (slightly) HP or is it just a better and more efficiant way of providing fuel to the engine?

Replacing injectors as a standalone mod does not increase hp. It is a supporting mod required when increasing engine airflow which increases injector duty cycle to the point of being static at WOT. As a result the ECM cannot supply enough fuel for accurate air fuel ratio. Increasing injector size simply allows for better and more precise fuel metering.

[Speed74SS]

Originally Posted by radz28

Thanks, Speed'

I just wanted to be clear that I was only commenting on the '12 that ADM tested for GTHMP. From the article, Andy reflected exactly what Speed74SS said about the injectors max'ing out. The '12 didn't, which surprised Andy, so maybe ZL1 and CTS-V are sharing more components than GM's announced. The more the better

Yes - that is very interesting. You would think GM would share the specs if they were making it better. Again, the ZL1 is making waves as an amazing car and we are all reaping the benefits