2012 GT500 safe max power with stock exhaust manifolds

[5.0rick]

Hey everyone,

I am debating on whether to leave the stock manifolds alone or go through the trouble of doing headers. Current setup consists of VMP Gen2R w/2.6 pulley (15psi), PMAS 120, 65mm TB, stock injectors (47lbs), 3.73 gears, stock mufflers. I would like a little more sound out of the exhaust but nothing obnoxiously loud. Thinking about installing a Lethal Performance O/R X pipe. Also would like a bit more power but don't plan or expect anything over 630 ish RWHP. Anyone running a similar setup?

Thanks in advance!

 

[HKusp]

Bigger injectors and a BAP, with the tune to take advantage and you'll hit your power numbers without the headers. As for exhaust sound, it's really a matter of personal taste.

 

[MG0h3]

Headers vs manifolds isn’t a safety issue.

Maybe if you’re making big big power and they are causing back pressure but you have nothing to worry about

19-20 psi here on stock manifolds for the last five years.

Absolutely ditch your cats if you have them. They’ll be a problem we’ll before stock manifolds


Sent from my iPhone using svtperformance.com

 

[5.0rick]

Thanks guys! I have some 56 lb injectors I have not installed yet. Need to get a BAP as well. Duty cycle on the pump looks good, injector duty cycle is pretty high so I guess these are a must.

 

[Islandcat]

I have a similar setup to you. I originally left my manifolds and just did off-road hpipe. I did it due to cost. A couple years later I bit the bullet and added headers. I think it gained 20-25 hp but more importantly the torque below 3,000 rpm felt so much stronger. Yea it’s pricey and not the best gains for the buck, but if you can swing headers and off-road pipe then I say do that.

As far as sound, I had Corsa at first but it was too loud for my taste. Put the stock mufflers on and while it is a bit quiet it does sound real good. Just probably could use a little more volume.

Edit: my car is an 09 with the 2.5 inch exhaust. I believe the 12 is 2.75. Leaving stock mufflers on that setup will probably be different than my experience with stock mufflers.

 

[IronTerp]

In most cases, Headers will not increase your peak RWHP much at all. What they will do is to maintain your peak power levels in the higher RPM ranges. If you’re a track junkie and are looking to hit a number, they would be a good addition.

Definitely not a great bang for your buck mod though. After purchase price, ceramic coating, and install costs if you don’t install yourself, you’re looking at easily 2k+ cost.