If you're pushing even more boost than stock, upgrading your six. 7 cummins valve springs and pushrods is one of those "boring" mods that actually retains your engine from exploding when items get rowdy. We all love the sound of a big turbo spooling up and the feeling of this extra torque pinning us to the seat, but individuals performance gains arrive with a hidden cost. The internal components that were perfectly fine for any 350-horsepower daily driver start to battle when you double that will output.
Most guys begin with a tuner, maybe an consumption, and a larger exhaust. Then comes the particular bigger turbo and higher-flow injectors. Before long, you're pushing 50 or 60 pounds of boost, and that's exactly exactly where the factory valvetrain begins to complain. It's not that Cummins built a weak engine—far from it—but they built this to fulfill a particular set of parameters from the factory. High-performance diesel creates usually blow correct past those parameters.
Why Share Parts Fail Under Pressure
Let's talk about why you even need to wreak havoc on your valvetrain to begin with. The six. 7 Cummins is a workhorse, yet the factory valve springs are remarkably soft. They're created for efficiency and long life at stock REVOLTION PER MINUTE ranges and stock boost levels. When you begin throwing 40+ PSI of boost on the engine, that atmosphere pressure is actually looking to hold the intake valves open up.
When your valve springs don't have enough "seat pressure" (the force holding the particular valve closed), the boost pressure may overcome the spring. This may lead to something known as valve float. When the valve doesn't close completely or even bounces from the chair, you lose compression, you lose strength, and in the worst-case scenario, your piston decides in order to have an extremely violent meeting along with your valve. That's a bad day time for everyone included.
Then generally there are the pushrods. If you've actually held a stock 6. 7 Cummins pushrod in your hand, a person know they aren't exactly massive. They will look more like heavy-duty drinking straws than high-performance motor components. When a person install stiffer valve springs to combat off valve drift, you're putting way more stress on those pushrods. Under high RPM or high load, those thin factory rods can in fact flex or bend. When they contract, your valve time is out the windows, and your engine starts running such as a bag associated with hammers.
The particular Magic of Heavier Valve Springs
Upgrading your springs is mostly regarding control. You need to make sure that no matter how much boost you're producing or how higher you're revving, that valve follows the camshaft profile exactly. Most aftermarket six. 7 cummins valve springs and pushrods kits offer a substantial jump in seat pressure.
Stock springs generally sit around 70-80 lbs of chair pressure. Upgrading to a "103-lb" or "110-lb" spring is an extremely common move with regard to street-strip trucks. It provides enough force to keep the valves seated even when the particular manifold pressure will be through the roof.
The elegance of these upgraded springs is that they don't simply protect the engine; they make it more efficient. Once the valves close cleanly and stay shut, you get much better combustion and more consistent power delivery. You might notice typically the engine feels the bit "crisper" at high RPMs because the valvetrain isn't battling to keep up with the demands of the camshaft.
Why Beefier Pushrods Are a No-Brainer
In the event that you're doing the springs, you absolutely possess to do the pushrods. It's almost a rule associated with thumb in the Cummins world. Mainly because the new springs are much more difficult to compress, the particular force required in order to open the valve increases. Your stock pushrods were never made to push towards that kind associated with resistance.
Top of the line pushrods are often produced from seamless crmo tubing and have much thicker wall space than the stock units. They don't flex. When the lifter moves up, every bit of that motion is transferred directly to the rocker arm and the valve. This "rigidity" is key to maintaining your own engine's timing and ensuring you're getting the full raise out of your camshaft. Plus, they're just way more difficult to break. Should you ever over-rev the engine or have a minor timing accident, a beefy pushrod might be the between a basic fix and a total rebuild.
Choosing the Right Setup for Your Build
Not really everyone needs the craziest triple-spring setup and 7/16-inch heavy pushrods. If you're just running a "hot" street tune and maybe a somewhat larger drop-in turbo, a set of 103-lb springs and heavy-duty 3/8-inch pushrods is usually a lot. It's an excellent "insurance policy" that gives you tranquility of mind with no being overkill.
However, if you're building a devoted drag truck or a sled puller, you're going to would like to go larger. Once you get into the realm of 800+ horsepower and 4, 000+ RPM, the demands within the valvetrain are crazy. At that stage, you're looking at significantly higher seat stresses and pushrods that will look like they belong in the piece of large construction equipment.
The key is to match the particular parts to your goals. There's simply no point in placing in springs that are so stiff they cause unnecessary use on your flat-tappet cam if you're only making 400 horsepower. But intended for most of us who can't depart well enough alone, a moderate upgrade is usually the sweet place.
Methods for a Smooth Installation
Swapping out six. 7 cummins valve springs and pushrods isn't necessarily "hard, " but it is tedious. You're working in a restricted space, especially close to the back from the head by the firewall (cylinders five and 6 are usually always a great time, best? ).
One of the biggest tips is usually to make certain you have the right tool for compressing the springs whilst the head continues to be on the motor. There are specific bridges made for the Cummins head which make this job ten occasions easier. Also, a person have to make sure you don't drop a valve into the canister. Most guys use the "top deceased center" method—rotating the particular engine therefore the piston for the canister you're working upon are at the pretty top. That way, when the valve slides, it only falls a fraction of the inch and strikes the piston instead of disappearing into the particular abyss.
Whilst you possess the rocker box off, it's also the perfect time to check your valve eyelash. Since you're currently in there messing using the pushrods, a person might as well get everything dialed in to factory specs (or whatever your aftermarket cam manufacturer recommends). A little extra time spent here will make the particular truck run very much smoother and quieter once you fire it back up.
Is This Worth the time and effort?
At the finish of the time, spending money on 6. seven cummins valve springs and pushrods isn't as "sexy" as buying a shiny brand-new turbo or a fancy manifold. You can't see them once they're installed, and they don't really change the exhaust system note. However they are foundational.
Think that of it such as building a house. You can put the nicest house and windows on it, but when the foundation is usually weak, everything is eventually likely to have difficulties. Upgrading your valvetrain is building that foundation. It enables you to use the power you've already built more properly and opens the door for even more upgrades down the road.
In the event that you're planning on keeping your vehicle for a long time and you like to use the right foot, it is really an upgrade you won't regret. It's about reliability, performance, and that wonderful sensation of knowing your own engine isn't going to turn itself in to a pile of costly scrap metal the next time you decide in order to pass someone on a steep quality. It's one associated with those modifications that will just makes feeling when you stop searching at the dynamometer numbers and begin looking at just how these engines in fact work under pressure.