So I've got my CAI done for good now after I heat treated it, new downpipe, reso and u-bend delete, coolant bypass line from milzy (once I get it), 180* T stat (soon), and soon a ZZP alternator pulley. My question to you guys is, what type of bigger injectors can I put in her to gain some extra horses?

I don't know what type and size the stock LA1 jectors are. I can get a set of used #24.7 @ 43.5psi ones, or #28.5 @ 55psi jectors. (those are said to be drop in replacements for the 2000 and newer 31 & 3400 motors)

I want something that puts out more fuel, but not alot. Like putting the 3.8L ones in?

Or should I just play around with my fuel pressure reg?

 

Fuel injectors don't give you more hp, they only allow you to make more hp when you need it. Plus without a PCM tune for it, you'll run rich and foul out your spark plugs constantly.

Back when my 3800 was NA I had some mods: a fwi, no cat or res, TOG headers, GT1 cam, w/p udp, 180* drilled tstat, p&p heads, thinner head gaskets (raised compression = more hp), p&p lim, HV3, a custom dyno tune at ZZP, and there may have been a few other things that I'm forgetting right now. Anyways, with all of that, I still didn't need to upgrade my injectors just to put things into perspective.

If you're worried that you're running out of injector though, have someone hook up an Powertuner to your Monte and see how they're doing. If they're running at less then 90%, you don't need to worry about new injectors.