Your ECU is throwing as much fuel as it can on the airflow (I think it can increase by up to 20%), and it's still not enough. It's compensating on the other end by pulling timing, but there are probably limits on what it can do there (I'm not an expert on the ECU, others here can comment better). The smallest problem you could have is glowing hot headers frying wiring; the worst you could do is internal engine damage.

As to why others don't care, well F-body guys aren't the most patient, level-headed people God created... I tend to be more cautious.

 

I hear you about the boosted 4 bangers... I had a 2010 Cobalt SS. You could pick up like 80hp with just an aggressive tune. Everything where you modify airflow will change how much fuel you throw at it. I still haven't tuned for my long tubes but I doubt its really going to do much to blow the motor with just my headers. But I'm going to tune it soon anyways. Its the safer thing to do. You can tune it before the cam and then get it revised later. Many tuners won't charge the full rate for some adjustments like that.

 

Already asked about tuning now and then cam later. The shop I want to go to (one of the best in the area), doesn't give a discount based on prior tunes.

 

My before and after cam. before was intake, Kooks with HFC and full catback.

After was with a tune and a baby cam.

 

whats the timing looking like from 5800 up? im not liking how your losing power past 6k

 

363 untuned? That's what I was hoping for.

 

you have to consider that you also ported a poor flowing manifold(stock). thats gonna bump air flow considerably more. brotha,you cant look at dyno numbers mod for mod because they will always be different. way too many variables. if you tune the car you will pick up alot..in terms of power and drivability. id get it tuned now and let that power sink in..then add the cam and maybe a few other mods at the same time later.

 

Cam will be my last power mod for a long time. Heads are too expensive and not interested in spray, or the added fueling needs that go along with it. After cam, it's just going to be reinforcing everything, i.e., LS7 clutch, suspension, etc.

 

Yes untuned. And what Punishment said. Dyno numbers are mostly meaningless. Especially on different cars/days/weather/dynos/altitudes etc.

 

I do not know. Had RPM install teh cam and tuned(Roshan). And it drives great. I assumed it was because of the relatively small cam I went with. Which I am ok with given the way the car didnt lose anything down low to mid range.

 

deff a healthy power band.. looks like your either running out of air (restriction) or he backed timing off. afr's look good.

 

KN to a stock LS2 intake. Considered having it ported. Was told not worth it. To either pony up for a fast or leave it be.

 

the fast is a waste with out heads.. you can deff straiten that line out with a ported tb. i just ported my stock ls2 tb and went off a ported one i had prior(motor **** the bed) there is a ton of restriction in there. i did mine mostly by hand with one section i used a file to knock it down. if youd like i can send you pics of how to do it if your good with sand paper and patience

 

Yeah, cost me $320 to have my intake ported. It's as hogged out as can be. Has all posts removed, plastic welded, smoothed over, etc. I figure it cost a lot less than a FAST and should give me some gains, albeit not as much. Hoping I can get my hands on a ported TB as well. We'll see after the cam goes in.

 

this mod here is why you are seeing lower numbers than most.. you are super lean bro. did they have a wide band in the pipe during the dyno run?

 

nah. If I mod further itll be a substantial gain. And I wouldnt do the TB or manifold without retuning it. And if I keep the car(keep changing my mind on selling it) I would save up and go heads and maybe just stroke it. Something like a 408 with a fast 92 and then I would do the TB. Or skip it and do a 102 on both.

 

Naw, I was surprised they didn't do AFR seeing that they charged $100 (I'm used to $70-80 for a couple pulls).

Funny you say it's why I'm seeing lower numbers...the guy who did the porting claimed 15whp on GTOs untuned. *shrugs*

 

I talked to multiple people including COMPANIES that offered it. And they said like 2 HP at most. Now I wish I did it as it would have broken that 400hp mark.

 

You will gain 20 HP with a FAST102, and you stand a good chance of gaining some driveability problems. Also, in my experience, the cam didn't add a huge amount of power to the LS2. I gained 20 HP peak, though I did gain a bunch under the curve. I gained another 20 with the FAST. I was sitting at 421 peak with cam and FAST. Money would have been MUCH better spent if I'd done it all at once and just done heads and cam.

My advice for you is to tune the car now, then save your pennies for heads/cam. Take your time and spec out a good value combo. Martin Smallwood is excellent for advice like that.

 

its a different car with a different stock tune and set up. motor is the same but the t56 is different as is the drive shaft and rear end. see where im going with this? all your missing power is in the tune. the computer can only correct so much on the stock tables..then it goes into survival mode and pulls timing to keep it together...hence the lower power