EVIL ENERGY’s LS Swap Fuel System Kit pairs an adjustable 6AN fuel pressure regulator with a 25-foot run of braided PTFE line and the fittings to join them. It is aimed at LS swaps and EFI conversions where one order beats sourcing every piece separately. The kit sits among the brand’s fuel parts, and you can browse EVIL ENERGY’s own store to find it.
I haven’t installed this kit myself. Everything below comes from the spec sheet, the brand’s published policies and what builders have posted on car forums, and I say which is which.
The short version: the spec sheet lists E85-compatible line and a choice of three pressure ranges, and the two things worth checking are how well the fittings seat on your wrenches and how hard your build will work the line.
What’s in the Kit
The kit is built around three main pieces plus the hardware that joins them.
- Regulator: a 6AN adjustable fuel pressure regulator in an aluminum housing the brand calls aerospace-grade.
- Fuel line: 25 feet of nylon-braided PTFE line.
- Fittings: 6AN fittings and adapters sized to suit LS swap and EFI plumbing.
- Pressure range: you pick one of three adjustment windows when you order.
Those windows are 30 to 70 PSI at the low end, 20 to 120 PSI in the middle and 30 to 140 PSI at the top. Check your injector and fuel rail specs first, then choose the range that fits them.
How the PTFE Line Is Rated
Here are the figures the brand’s spec sheet gives for the line.
- Inner diameter: 5/16 inch.
- Working pressure: 1,500 PSI.
- Burst rating: 4,500 PSI.
- Temperature window: negative 76°F to 446°F.
- Listed fuels: gasoline, diesel and E85.
The material, polytetrafluoroethylene or PTFE, is the reason E85 is on that list. The brand’s spec notes say it resists ethanol permeation, and its compatibility notes call for PTFE whenever the fuel is E85, methanol or another ethanol blend.
CPE is the brand’s other main hose material, cheaper and meant for gasoline only. Because this kit ships with PTFE, that choice is already made for you.
Who the Kit Fits Best
It makes the most sense for a daily-driven LS swap or a mild EFI conversion on a real budget, where getting the regulator and the line in one order saves time.
If you plan to run big boost or race the car, builders on car forums often point toward a premium line from Earl’s Performance or Fragola for the fuel line itself, while keeping EVIL ENERGY for less demanding parts. The brand does not present this kit as race-grade, and it fits best as a street-build setup.
For context, Earl’s Performance Plumbing has decades of history with AN plumbing and is owned by Holley, while EVIL ENERGY dates from 2016 and describes itself as a direct manufacturer. In practice that shows up as standard AN sizing on the Earl’s side and a one-order bundle on the EVIL ENERGY side.
Track and drift builds that need more capacity can look at the brand’s separate fuel cell tanks instead, which range from 1 to 20 gallons.
Parts That Pair With the Kit
A few other listings from the same maker slot into a swap like this. The prices below are approximate figures from EVIL ENERGY’s store and can change, so confirm each one on the product page.
| Part | Key specs | About |
|---|---|---|
| Inline fuel filter | Aluminum alloy housing, stainless steel element, 10, 30, 40 or 100 micron | $42 |
| PTFE hose end fitting | 6061-T6 aluminum, 360-degree swivel, 3AN through 12AN | $9 each |
| Fuel cell gas tank | 1060-H24 aluminum, anti-slosh foam, level sender | From $70 |
| External inline fuel pump | Rated at 300 liters per hour | $60 |
The filter’s stainless element comes out for cleaning, so it is reusable rather than disposable. Micron rating is a trade-off: 10 micron traps the smallest particles and suits fuel injection, while 100 micron works as a coarse pre-filter better matched to carbureted engines.
At about $9 each, one hose end fitting is the lowest-priced item in this table. That makes it an easy way to judge the brand’s machining and wrench fit before you commit to a full kit.
Fuel cells are the pick for track, drift and off-road builds. If a cell will carry E85 or methanol, plumb it with PTFE, which the brand’s compatibility notes require for those fuels. The brand also offers master kits that bundle a pump, and the standalone pump can either join a cell kit or stand in for a worn factory pump.
What to Check Before You Buy
This section stands in for owner praise, because I only quote feedback I can attribute. What follows comes from car-build forum threads that discuss the brand.
Fitting tolerance
In a Yellow Bullet fittings discussion, and in other forum threads, builders say the AN fittings bundled with some kits come in slightly off standard dimensions, so a common -6AN wrench may not grip cleanly. A non-marring adjustable AN wrench is the workaround they mention. Because cut line cannot be uncut, try your wrench on a fitting first.
Long-term line durability
Some builders say the brand’s PTFE hose ages faster under sustained heat than lines from Russell, Earl’s or Fragola. That comment is about the line family in general, not this exact kit, but it is a fair thing to watch if your engine bay runs hot.
First start and first miles
Do the first leak check with the engine off: pressurize the system and look at each connection for weeping. Do a second pass after 50 to 100 miles, because heat cycles can show up a fitting that felt tight when it was cold.
Matching any extra line to the fuel
The kit’s line is PTFE, so it suits ethanol fuels. If you add more hose from the catalog later, keep to PTFE whenever E85, methanol or an ethanol blend is involved, because ethanol running through CPE line speeds up wear.
Care and records
Upkeep is light. The filter element can be pulled and cleaned, and the arrow on its housing should point in the direction the fuel flows. Hold on to the order confirmation and your install photos as well, because a quality-issue claim with the brand needs photos or a video clip.
Warranty, Returns and Shipping
One year is the minimum warranty the brand lists across its products, though each item can differ. Some fuel system parts get only six months, so look up the warranty on the exact listing for the kit you choose.
The return window is 180 days, split into two tiers. Through day 90, a kit that is unused, uninstalled and in its original packaging can go back with free return shipping. Between day 90 and day 180 it is still accepted, but a 15 percent operating fee applies.
Who pays for the return trip depends on the reason. A defective part, or one that differs from its listing, ships back at the brand’s expense once you send photos or video. A wrong order or a change of mind leaves the postage to you, and you need to email the brand within 30 days of delivery.
Orders above $50 ship free, and the brand states that support emails get an answer within 24 business hours. Coverage applies only to orders placed through its official channels, so if you buy anywhere other than EVIL ENERGY’s own site, make sure the seller is authorized.
Questions Before You Order
Which fuels is the line rated for?
The brand lists gasoline, diesel and E85.
Can I run E85 through CPE line instead?
No. The brand’s compatibility notes require PTFE for E85, methanol and ethanol blends, and CPE suits gasoline only.
Are these original manufacturer parts?
No. The brand states that its parts are aftermarket and not affiliated with any car maker, so a listing does not imply a factory partnership.
Does the brand make its own parts?
The brand says it does. It describes itself as a manufacturer selling direct, with Canadian factory space of about 10,000 square meters and a workforce above 300.
Where is the company based?
The company is based in Diamond Bar, California, and holds stock in three U.S. warehouses, located in New Jersey, Georgia and California.
The Verdict
Anyone planning an LS swap or EFI conversion who wants one order to cover regulator, line and fittings will find this kit a convenient package. The listing gives you an adjustable regulator, 25 feet of PTFE line rated for E85 and a choice of three pressure windows.
Best for a daily-driven swap or a mild EFI build. Less suited to big boost, nitrous or serious track use, where forum builders lean toward a premium line for the fuel line itself.
It is not a race-grade setup, and the forum reports on fitting tolerance and long-term line wear deserve a fair hearing. Test-fit your wrenches, leak-check the system and recheck after the first miles, and you will have covered the points forum posters raise about the brand.
Ready to price it? Browse EVIL ENERGY’s store and look for the LS Swap Fuel System Kit, where you can check the current price and pick your pressure range.
