Jenn_5.0

Ok, so I have a 2011 Mustang GT 5.0....I already have a Boss 302 Intake Manifold, should I just keep it, or go for the Cobra Jet. I was told to keep it because it's essentially the same thing. But a couple of my buddies insist on the Cobra Jet. I will be honest will you, I am way new to Mustangs, and I just don't wanna blow money on car parts that are virtually the same thing. lol. Forgive my ignorance. :P I have a lot to learn. )

Menace

The Cobra Jet is a better intake, but you will need a different throttle body and a different CAI to use the Cobra Jet. So that increases its costs even more so (not even sure if they are available)

Depends on what you want to do with your car really, and if that extra (maybe 10-20rwhp since you gotta upgrade the throttle body as well) is worth the price.

Also, the Cobra Jet's runners are longer so if you have a strut tower you will have to remove that (currently, to my knowledge no towers will fit over the Cobra Jet) and basically when you change up the runner length you are affecting many different things in the car. Power curves, max RPM, air flow, etc...

Jenn_5.0

Thanks for the input. I don't know what to do! Seems like a lot of work. But I will do things only if its worth the money...lol.

SpartaPerformance

It's not, the Cobra Jet is a better manifold however the power gains vs the cost being you already have a BOSS.....save your money

JIM5.0

You should stick to your Boss intake because it is a good compromise between DD and high RPM power.

Here is why: the stock Coyote intake has longer runners than the Boss or CJ intakes for decent torque at low RPM bandwidths.
The Boss intake has shorter intakes than the stock Coyote intake to shift the torque curve towards the upper RPM bandwidths to yield more power in higher RPMs. The compromise being you lose some torque in the lower RPM bandwidths.
The CJ intake takes it a step further and has even shorter runners than the Boss intake, thus shifting your torque curve even higher in the RPM bandwidth. And just like the Boss, you sacrifice low end torque. The CJ unfortunately scarifies more torque than the Boss does.

The only way to help eliminate this phenomenon is to not even use a stock Coyote, Boss, or CJ intake. You would have to use an intake that does not even exist for Mustangs. You would have to design a variable length intake from the ground up.
If anyone were up for the task to actually fabricate such a beast, he/she would have to build such an intake using 2 methods:

1) Multiple variable length runners: This is where you have a long runner and a short runner. You switch from one to the other depending on RPM. At low RPMs, you use the long runners. At high RPMs, you use the short runners.
Switching runners is done with something as simple as butterfly valves.

2) Telescoping runner: Only uses one runner, but it changes its length by telescoping in and out like those ancient radio pull-out antennae. For low RPMs, the runners are extended out. For high RPMS, the runners are pushed in to a shorter length.
The benefit telescoping runners is you can set them for multiple lengths, not just two set lengths. You would need a stepper-motor to actuate the runners to lengthen and shorten the runners.

Mr2013GT

Keep the Boss manifold.

Your powercurve drops off quickly after 6,500 rpm with the stock manifold. With the Boss 302 manifold, your power just hangs there, even after 7,500 rpm. I'd imagine the Cobra Jet manifold would gain you a little bit of peak hp over the Boss manifold and power would still hang there up high too, but last time I checked, the Cobra Jet manifold is around $900, not including a throttle body + strut tower brace, if they even make them for the CJ manifold.

If you were considering shelling out almost a grand for a new intake manifold that probably wouldn't change much over the Boss manifold, and would require additional parts that aren't exactly cheap, I would think you'd be better off just buying a set of Comp Cams Coyote NSR camshafts, stage 2's gain about 30-35 rwhp and move your peak hp up to around 7,000 rpm, stage 3's move you peak hp up to 7,200-7,300 rpm and gain you 49 hp and climbing at 7,500 rpm. All 3 stages are $1,500.

JIM5.0

+1 on what Mr2013GT said especially about the cams.

Adding on a high RPM intake is one thing, but unless you have the cams to support that additional air flow, it's like pissing in the wind and you would be out the money when the Boss intake is more than up for the task on stock Coyote cams.

Menace

Ford claims no loss of torque with the Cobra Jet compared to the Boss intake.

If I had a 11+ Mustang I would go with the Cobra Jet, cams in the future, etc. Though if I had a Boss Intake I wouldn't upgrade really. There are other areas you could upgrade first.