The Upgrade Instructions for the 5.7 HEMI Intake Manifold. The 5.7 HEMI is a terrific engine, but it is notorious for being underpowered out of the box. It’s understandable given that the massive 5.7L V8 produces only 400 horsepower. However, with a few bolt-on improvements, the 345 HEMI has a lot of potential. A 5.7 HEMI intake manifold improvement is one of the best upgrades. This page goes over 5.7L HEMI V8 intake manifold upgrades, power improvements, benefits, and expenses, among other things.
Advantages of 5.7 HEMI Intake Manifold
The advantages of upgrading a 5.7 HEMI intake manifold depend on your aims and the exact manifold in issue. Nonetheless, some of the potential advantages of 5.7L HEMi intake upgrades include:
- Peak power improvements of 5-10whp
- Midrange gains of 10-20whp and 15-30wtq
- increased fortification
- improved audio
- improved engine bay appearance
Power improvements might vary greatly between intake manifolds. As a result, we’ll talk about power improvements in the section below and then return to horsepower when we talk about individual manifolds.
In any case, the factory manifold on the 5.7 HEMI V8 is made of plastic. A 6.1L HEMI manifold, like many aftermarket choices, is made of aluminum. The plastic manifold on a NA engine is sufficient. If you’re considering boost, you’ll probably want something that’s a little stronger and flows better.
Furthermore, 5.7 HEMI intake manifold upgrades can increase engine acoustics and make the engine room look cleaner. That is all subjective, therefore it may not be much of a benefit for some.
HP Increases for the Dodge 5.7L V8 Manifold
Peak power improvements from a 5.7 HEMI intake manifold change aren’t always spectacular. Depending on engine modifications, tune, and other circumstances, you may notice tiny 5-10whp improvements on top. Even if the peak gains aren’t spectacular, an intake manifold isn’t a waste of money. The true value of manifold enhancements is shown in the mid-range.
Some have seen improvements of 10-20whp and 15-30wtq in the mid-range using a 6.4L HEMI manifold. That’s where most of the real driving takes place, and those are good power gains. You’ll definitely notice the extra power, which makes an intake manifold well worth the investment.
However, we believe that other power mods, such as a tune, headers, cams, and so on, are a better place to start. All of these mods can provide tremendous mid-range power and torque boosts while also helping to boost top-end output. As a result, an intake manifold didn’t make our list of the top 5 5.7 HEMI upgrades.
Don’t let it deter you from upgrading the 345 HEMI intake manifold. It’s still an amazing mod, and if you want to optimize NA power, a manifold is a must-have. We would simply advise starting with other performance upgrades before upgrading to an intake manifold.
*The power improvements listed above are preliminary estimations for the 6.4L HEMI manifold modification. Some manifolds may actually shed some lower-end power in exchange for higher top-end gains. When we discuss specific 5.7 HEMI intake manifolds, we shall clarify.
Upgrades for the 5.7 HEMI Intake Manifold
With some background information and benefits out of the way, it’s time to get into the greatest 5.7 HEMI intake manifold improvements. Please keep in mind that this is not an exhaustive list. There just isn’t enough time or space to cover every available upgrade.
Instead, we’ll concentrate on some of the most popular and greatest 5.7 HEMI upgrades. It is critical to understand your goals before selecting an intake manifold. Anyway, let’s get right into it and talk about some of the best HEMI manifold tweaks.
1) Upgraded 392 HEMI Manifold
Price: $769 – $1,616
Power Gains: 0-10whp maximum (10-20whp middle)
In the intake manifold of the 6.4L HEMI, active runners are used. The 392 manifold functions in long-runner mode up to 4,800rpm to help with power and torque. To help with top-end power, it then shifts to short-runner (the design of most 5.7 HEMI manifolds*).
This is a major reason why the 6.4L manifold rarely provides top-end benefits. At higher RPM, where peak power occurs, it basically acts like a standard 5.7 manifold. Active runners, on the other hand, significantly improve low-end and mid-range power.
In the midrange, power improvements of 10-20whp and 15-30+wtq have been observed. You could even port the 6.4 manifold for even more power and torque. The 6.4L V8 HEMI manifold bolts right on to the 5.7L engine. However, getting the active runners to function on the 5.7 HEMI involves additional wiring and tuning.
If naturally aspirated performance is your aim, this 392 HEMI manifold is an excellent choice. It’s plastic, exactly like the 5.7 HEMI intake manifold, so it might not be the ideal choice if you’re seeking for aesthetics. If you intend to add boost, you should also consider a stronger aluminum manifold.
*The revised 5.7 Eagle in the Ram 1500, like the 6.4 HEMI intake, has a manifold with active runners.
2) Porting of the 5.7L V8 Intake Manifold
Price: $400 without the core charge
Gains in power: 5-10whp
Another popular and common solution is to just port the OEM 5.7 HEMI intake manifold. The objective is to simply remove material in order to increase the size of the runner ports. They are then smoothed to provide optimum airflow while minimizing turbulence.
It’s a straightforward solution that’s less expensive than upgrading to 6.4 HEMI or aftermarket manifolds. However, the power gains will be less dramatic. Top-end improvements of 5-10whp are likely, but you’ll sacrifice some midrange torque.
In the end, this isn’t the best solution or improvement available, but it’s a less expensive option. However, if you’re seeking for a quick boost without breaking the bank, it’s a viable choice.
Some 5.7 HEMI owners upgrade to the aluminum 6.1L HEMI intake manifold. However, we do not consider that to be one of the best manifolds. In general, porting the factory 345 HEMI manifold, upgrading to the 392 HEMI intake, or going with an aftermarket design are preferable options.
3) Edelbrock Intake Manifold 5.7 HEMI
Gains in horsepower: 5-15whp
Finally, we’ve arrived at a genuine aftermarket intake for the 5.7 HEMI. For good reason, Edelbrock is a popular choice. It’s built of aluminum and has a similar design to the factory 6.1L HEMI manifold. It does, however, have a larger plenum and 14′′ tapered runners. To alleviate port obstruction, the Edelbrock manifold relocates the injector bosses.
To summarize, the Edelbrock 5.7 HEMI intake manifold is preferable to the 6.1L manifold. At around $1,080, it’s also comparable to upgrading to the 6.1 HEMI manifold. On the upper end, expect improvements of 5-15whp. However, you will sacrifice some mid-range torque in exchange for more top-end horsepower.
4) Holley Sniper Intake Manifold for Gen 3 HEMI
Gains in horsepower: 5-15whp
Last but not least is the Holley Performance Sniper Intake Manifold. It’s designed to fit the Gen III 5.7L HEMI from 2009 and up, as are the majority of the things on the list. It comes with the high flow fuel raid kit, mounting hardware, and o-rings.
It’s one of the more affordable intake manifolds on our list, and we believe it looks great. This manifold should produce similar improvements of 5-15whp while sacrificing some low-end performance.
However, the Holley Sniper 5.7 HEMI intake manifold looks fantastic. If you’re looking for a long-lasting, attractive manifold, this is an excellent value. Still, if maximal performance is the aim, the 392 HEMI manifold with active runners is likely the best option.
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Is it worthwhile to upgrade the 5.7 HEMI manifold?
Both yes and no. Again, this is a matter of opinion. What are your intentions with the car/truck? Are you willing to invest in an intake manifold? Do you think other changes would be better for your build? There is no one-size-fits-all solution.
Finally, an intake manifold might be a terrific alteration for the 345 HEMI. We believe the 5.7 V8 would be better spent elsewhere. But that’s just our opinion. If you detest the design of the plastic manifold and want a stronger, more attractive aluminum intake, this could be a great alteration.
If you want to get the most out of your NA 5.7 HEMI, you should consider upgrading the intake. We’d just move this modification down the list after stuff like tune, headers, and cams. Regardless, the appropriate intake manifold for the Dodge 5.7 HEMI can provide some respectable power boosts.