Crimp or Socket AN- Hose Ends: Making a Choice for Your Race Car

Technology in the AN-style plumbing department is changing as it pertains to making A to B fluid connections in your race car. We reviewed the Earl’s Performance Plumbing components going together on the revamped “Project Evil.” The Mustang is undergoing updates to become a Vortech-supercharged 1,800-horsepower monster for X275 competition.

With fresh re-engineering of the project Mustang comes a complete change in plumbing to route the fuel, oil, and cooling systems. A combination of Earl’s UltraPro Series hose and Auto-Crimp hose ends are completing the connections.

The new powerplant is comprised of a KBX billet-block 351 Windsor equipped with a FuelTech FT600 electronic fuel injection system to supply the methanol fuel demanded for that kind of horsepower. For plumbing the massive EFI system, the hoses and ends are assembled using Earl’s Performance UltraPro Series PTFE-lined hose, and Auto-Crimp hose ends.

We talked to Jim Szilagyi, Senior Merchandising Manager for Holley Performance/Earl’s Performance Plumbing brand, about the varied hose ends as they are combined with Earl’s AN-style fitting lines.

Available in both braided stainless steel and poly braided outer sheath, the poly hose used is carefully cut to length with a sharp knife. An advantage of the Earl's UltraPro hose products is the ribbed design of the PTFE liner. This liner allows for tighter bends compared to a traditional solid liner design.

“The Earl’s UltraPro features a Polytetrafluoroethylene (PTFE) material in the inner lining that is resistant to all known fuels, oils, and coolants used in automotive and racing applications, including harsh methanol and ethanols,” describes Szilagyi. “Our PTFE-lined hose is becoming more popular because of that durability.”

The double-helix ribbing on the inner lining is unique to a few manufacturers, including Earl’s Performance. The ribbed lining makes it more flexible than some PTFE lining that is straight cast. When it comes to plumbing the tight bends within a race car, that flexibility is valuable.

“Any lines of hoses not compatible with ethanol or methanol are clearly spelled out in our catalogs and website,” offers Szilagyi. “These incompatible hoses with a rubber composition will begin to deteriorate. The hose will then allow vapor to escape through the hose and ultimately will follow with leakage.”

With the crimp collar installed onto the hose, the fitting is lubricated and fitted into the hose's PTFE liner. The hydraulic crimper is outfitted with crimp dies matching the hose and fitting. For budget racers, Earl's Performance offers a hand-operated crimper suitable for placing their Auto-Crimp hose ends on many different hose designs.

The Auto-crimp hose ends used on the project Mustang are a technology accepted by more and more high-end teams wanting to invest in the most secure AN-fittings possible. It’s no small expenditure to outfit your shop with a hydraulic crimping machine such as the Earl’s D100 Series Crimper.

The hose end assembly is carefully located within the crimping dies, and approximately 35 tons of clamping force creates an absolute connection between the hose and fitting. The crimped collar is then checked for proper final diameter with a set of calipers.

“Earl’s offers a hand-operated crimping tool that can install our Auto-Crimp hose ends,” says Szilagyi. “But, for the combination of PTFE hose and crimped hose ends, I personally recommend a hydraulic crimper and the 35 tons of clamping force it offers.”

Purchasing your own hydraulic crimper may be cost-prohibitive for many, but many racers utilize a friend’s unit or a commercial shop in their area that will allow the use of a crimping-style machine to get the job completed.

Earl’s Performance’s Jim Szilagyi highly recommends their pressure test kit to check crimped or screw together fittings. Simply cap each end with the appropriate adaptor, fill with compressed air based on the hose pressure rating, and submerge in water to seek out any leaks.

Though not recommended for use with the hose we used, Earl’s hand-operated crimping tools are slowly gaining popularity to install crimp hose ends on plumbing jobs ranging from Earl’s Perform-O-Flex braided steel hose to Pro-Lite 350 braided nylon hose lines. Earl’s offers an informative “How to Choose Fuel Hose” video to help with your product decision-making process.

“Our traditional compression hose ends that thread together are still the most viable option for all plumbing, including the UltraPro PTFE hose,” Szilagyi finishes. “The maximum pressure ratings of our products are based around the hose capacity. If you look at the spec sheets for our many hose options, the pressures they can handle are all specified in the hose, not related to the hose ends.”

In the past, there was a trade-off between PTFE hose durability and the lack of hose flexibility. Between the double-helix ribbing of the UltraPro hose and the crimped connection of the Auto-Crimp hose ends, plumbing Project Evil for its extreme duty is an accomplishment in durability.

No matter which combination of hose and ends you choose for fuels, coolants, or oiling applications, there is a multitude of choices available from Earl’s Performance.

Whether it be crimped or threaded hose ends, combined with a wide variety of hose materials, proper assembly procedure is the key to creating a foolproof plumbing job.

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Todd Silvey

Todd has been a hardcore drag racing journalist since 1987. He is constantly on both sides of the guardwall from racing photography and editorship to drag racing cars of every shape and class.
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