CAUTION! LONG READ! BUT ALL HELP IS APPRECIATED!

I'm almost done with modding my '06 Cobalt SS/SC, and all I need to do to finish it up is bigger injectors, spark plugs, and a custom tune, all of which I'd like done by Valentine's Day. My current engine mods are a 2.80" pulley (on stock injectors), Stage 2 belt, ZZP tensioner, and an Injen CAI. All I'm looking for in modding my car is something that's faster than stock, but nothing that NHRA says I need a rollcage to drive. Thus the bolt-on route.

The reason I've been holding off on the injectors and tune is that I just haven't driven my car a lot lately. But with wintertime upon us, I figured it'd be a good time to prepare for the summer. But on to my three-part question (excuse any n00b-ness):

1.) I know my stock injectors are pretty much maxed, and the CAI isn't helping them too much either. What's got me a little confused is that I've seen a lot of Cobalts running the same pulley saying they got by with 42.5 lb/hr injectors, while some say that those struggle with that size pulley and ended up swapping for 60 lb-ers. This is the question I'm most concerned with answering.

2.) I'd like to swap out the spark plugs as well, but I'm not sure which direction to go. On the one hand, platinum or iridium plugs last longer, but I hear that copper plugs are better for F/I applications. If you ask me, performance > durability in this case, but I don't know if there's any truth behind what I was told. And whatever plugs I get, how many steps colder should I get? I hear a lot of people wanting to go two steps, but wouldn't that be excessive? Isn't one sufficient in this case?

3.) I of course know that swapping out the injectors will require a tune, and the reason I didn't just go with a Stage 2 kit is because the pulley is a little bigger than I wanted, plus I hear that the reflash does the car more harm than good. Now, I know NOTHING about tuning a car. I've never done it, nor have I seen it done. So, of course, I wouldn't tune the car myself; I'd entrust the job to someone with the experience. I would also, obviously, like to be around when it's being worked on. I'd just like to know what kind of things I should be looking at or asking. You know, A/F ratio, knock retard, etc.

Thanks for reading, and like mentioned before, ALL HELP is appreciated! The sooner I get this done, the sooner I can start on appearance mods!

 

#1- Go with the 60's just for the peace of mind.

#2- ZEX plugs. No gapping, just pop them in. They work fantastic. Part #82003-4

#3- Find a shop with a dyno and that has used HPTuners before.

 

I had hooked ya up with a half-way decent answer on the Forum homie

 

As far as maxing out your injectors...Yes, the 42's are being pushed a bit too hard with that pulley. The people that are doing ok with theirs either, don't know how hard their injectors are actually working or are in higher elevations with warmer climates. I am running the 2.79" and have been doing so on the 42's for a couple months now. I am in the process of getting the money together for the 60's though, especially knowing how good the chances are that I may run her lean.

As far as plugs go, you could go with the NGK's which is what I'm running and one-step colder should do you fine with your setup.

Now, for the tune...This is all new to me as well, and I don't see why you couldn't ask as many questions as need be while they are doing the tune. I know I will be. Just make sure that you tell them that you want a mild tune that will give some leaway for the chance of colder weather because of your concern about her running lean. Better safe then sorry. Also, see if you can get a print-out or have them email you all the data that they recorded, i.e. A/F ratios, knock, ect...This way you have the info at your fingertips for viewing and future comparison reasons. That should also keep your butt covered if something were to happen.

Here ya go..lol

 

i would go with 60s, there are many guys with no probs with 42s and 2.8 but i think there has been a few with probs, plus if you ever wanted a smaller pulley, you wont have to buy injectors again..

NGK BKR7e

either find a local shop for tuning or jim at tag can set you up with a tune and injectors

 

1.) Get the 60lb-ers, dont make the mistake i did.
2.) Get copper plugs, NGK preferably, i have Zex plugs but dont like the. I plan on getting NGK's. Who cares about longevity of plugs, there what at most $30 to replace. You bought a performance car so buy performance plugs.
3.) Cant help with the tuning because i dont know how to do it myself.

 

when you say stock injectors......
are you referring to the 42lb stage 2 injectors?
or the STOCK injectors that came with the car.....because i can see you didnt get GM stage 2.......

 

The stock, out-of-the-factory injectors.

Thank you all for your responses. And sorry for the double-thread; the site was acting up last night. I'll be looking around for a tune thru next week.

 

I know... I posted this shortly before you responded on the Forum.

 

bro the 42lb stage 2 injectors cant keep up with a 2.8 pully, and your running one on the stock injectors????

your lucky your engine hasnt exploded yet.

 

Link? Very interested, and I couldn't find a thread.

 

https://www.cobaltss.net/forums/2-0l-lsj-performance-tech-47/2-79-60lb-tune-group-buy-42011/