You want more power.
You know that for sure.
What you don’t know is why your new headers—the headers you bought to help you get that extra power—just won’t fit your vehicle. You gave your sales rep your vehicle application, the intended purpose of your vehicle, and where you’d like to see your power gains on the power curve. They just won’t fit. And no combination of sheer will and assorted curse words is going to change that.
So what went wrong?
Working with the Summit Racing technical department, we’ve identified seven of the most-common reasons why a new set of headers won’t fit the intended vehicle (outside of being the wrong application altogether). If your newly purchased headers won’t fit, the culprit can likely be found below. If you haven’t bought your headers yet, read up on the seven pitfalls below and avoid them at all cost.
#1: You’re Out of Order
In some cases, you’ll find that there is a sequence that must be followed to complete your header installation. This may include the removal of certain items to make the headers fit.
During the buying process, it is important to take note of any footnotes that come with the product description. Take time to go over any footnotes or installation notes with your sales rep if ordering by phone. Once you have your headers in hand, pay close attention to the instructions, being careful to not skip steps.
#2: Improper Swap Mounts
Engine swaps have become increasingly common.
In some swaps, the engine location may change. This is especially commonplace in vehicles going from a small block engine to a big block and vice versa. If the correct mounts were not used during the swap, engine height and location within the engine compartment will be altered, causing fitment issues.
Since all headers are designed around factory engine mounts, you’ll need to make sure you use the proper engine mounts for the swap. This will locate the engine in its proper spot and help alleviate header fitment issues.
#3: Wrong Installation Direction
If you’re standing over your engine bay during the attempted installation, you’re doing it wrong. At least in most cases.
Most headers are designed to be installed from the bottom of the vehicle. Furthermore, your car or truck will likely need to be lifted at least 18 inches off the ground to get the proper installation angle. If you’re not fortunate enough to have access to a lift, it’s time to drag out the trusty old jack.
#4: Options in the Way
What options does your vehicle come with?
Again, this goes back to reading any footnotes with the product description. If you don’t have a manufacturer’s catalog handy, it’s probably best to pick up the phone and speak with a sales rep who does. Air conditioning, power brakes, power steering, and other options may present some extra installation challenges. In some instances, an extra bracket or option may need to be deleted.
#5: 4WD Fitment Issues
Not all truck headers are created equal.
If you’re installing your new headers on a truck, four-wheel drive versions will be bent differently to accommodate the transfer case up front.
Make sure you didn’t accidentally order or receive a set of two-wheel drive-friendly headers for your 4 x 4.
#6: Unique Head Cases
Have you installed aftermarket heads on your engine?
Some heads require a special set of headers because the cylinder head manufacturer has changed the port design, port location, and spark plug location. These changes may mean the headers simply won’t bolt up to the cylinder heads properly.
Remember what we said about reading all the footnotes? It applies here, too, as most manufacturers will make note of special cylinder head requirements.
#7: Worn Engine Mounts
Worn engine mounts and even chassis flex can cause the engine location to change slightly. Unfortunately, even a 1/8-inch difference in location can cause interference for your new headers. And that means your header flanges won’t sit flat against your cylinder heads.
To get your headers to bolt on properly, it may be time to replace your engine mounts or any other worn components causing the misalignment.
One final note: It is not uncommon for headers to have dents in the primary tubes right from the box. This is not a defect; the manufacturer often creates the dents in the tubes to solve some of the very fitment issues we’ve been talking about. If the paint or coating on the headers is not broken or cracked by the dent, the manufacturer intentionally put the dent there.
yes most headers are a pain I have seen very very few just drop right on place with out much effort or removing stuff and jacking motor up but hey it takes work to get extra power got to be willing to do it and do it right the first time and yes headsets do require. reading and following the directions step by step very few if any shirt cuts unless you have the motor pulled and are replacing the headers at the same time your putting a motor in and sometimes that don’t work out the easiest either
header on a 1951 dodge pickup with a 5.9 in it
I have a 69 Camaro with a 350 engine newly built for me by the Engine Factory in Lebanon NJ . I can’t find a header that clears the steering box on the driver side . Is this a common problem for the 69 Camaro ? Can you please recommend any solution and maybe a source for me to buy headers that will clear the steering box
We have a few different designs for this Application..
You can call Hedman Hedders at 562-921-0404 for more information.
Hello.. I have been searching for headers for my 1993 Chevy Chevy Silverado 1500 that I have swapped engines from 350 to 454.. either they would hit the frame on the passenger side or they were no longer available .. so after 4 sets of headers that have purchased I am hoping that this last an final set lucky number 4 that I got from headman headers will fit.. an suggestions I would greatly appreciate
Hey Wyatt, cool truck build! Have you looked into any of the 454 SS applications? You probably already know this, but the 454 SS was basically a 1500 truck that left the factory with a 454, so there may be a solid owners group or forum thread that could help. I checked Summit Racing and they had a few applications for a 1993 Chevy 1500/454, but you should probably contact their tech support folks for some more direct guidance.
And you can always call Hedman Hedders at 562-921-0404 for more information.
After months of frustration, all I want is a set of headers that fit. I’m tired of being lied to. I have a 69 Firebird with an Art Morrison front subframe and LS7 engine. Ultimate Headers with their vaunted short-radius block hugger turns, don’t fit, either long tube or shorty. American Racing Headers won’t even fit the engine out of the car on a stand. I’ve decided to take the ARH headers, cut away the offending tubes, and make “detour” tubes around the obstructions. I didn’t want to tackle TIG welding thin-wall stainless but it’s the last resort. Am I the only one with a liquid-liquid oil cooler?