ISR Performance S13 SR20DET Turbo Lines - Bottom Mount

The ISR Performance S13 SR20DET Bottom Mount Turbo Lines are a direct replacement for the factory turbo hardlines on the bottom-mount-turbo Nissan SR20DET in the 1989-1994 240SX (S13). Steel-braided lines with aircraft fittings and new aluminum crush washers. Replaces aged, leaking factory hardlines with a clean, leak-free upgrade.

What It Does

Factory SR20DET turbo oil and water hardlines are now 25+ years old on most S13 builds. They develop pinhole leaks at the fittings, the rubber junctions harden and crack, and they're generally past their service life. The ISR braided replacement lines solve all of that at once with stainless braided hose, aircraft-grade fittings, and new aluminum crush washers for sealing. Cleans up the engine bay significantly and eliminates a chronic source of oil weep and coolant seep on aged SR-swap builds.

Premium Hose Construction

The ISR braided lines use the newest Racing Hose with a pre-dyed black Nomex cover for peak performance and fade-resistant appearance over time. Kevlar reinforcement in the Nomex cover improves abrasion resistance and overall hose strength. The hose assemblies are up to 45 percent lighter than conventional high-performance racing assemblies, with a smooth, firm inner tube of black nylon-reinforced synthetic rubber.

Critical Ball Bearing Turbo Note

If you're using these lines with a ball bearing turbo (such as OEM S14 or S15 SR20DET turbos), you need to install an additional oil restrictor - NOT included. Ball bearing turbos require restricted oil supply or oil will back up past the seals and into the intake or exhaust. The ISR oil restrictor for ball bearing turbos is IS-OR-3036.

Turbo Position Note

These lines are specifically for the BOTTOM-MOUNT turbo configuration. If you're running a top-mount manifold (RamHorn or similar), use the top-mount line set (IS-T25-NS13-EXT) instead.

Fitment

• 1989-1994 Nissan 240SX (S13) with SR20DET
• Bottom-mount turbo configuration
• Compatible with factory T25, T28, or aftermarket T25/T28-frame turbos

Related Line Sets in the S-Chassis SR20DET Family

• S13 bottom-mount (this product, IS-T25-NS13)
• S13 top-mount: IS-T25-NS13-EXT
• S14 bottom-mount: IS-T25-NS14
• S14 top-mount: IS-T25-NS14-EXT

What's in the Box

• ISR Performance steel-braided turbo line set (S13 SR20DET bottom-mount)
• Aircraft-grade fittings
• New aluminum crush washers

Product Details

Brand: ISR Performance

Part Number: IS-T25-NS13

Type: Turbo Oil and Water Line Set (Bottom Mount)

Vehicle Fitment: 1989-1994 Nissan 240SX (S13) with SR20DET

Turbo Configuration: Bottom-mount

Engine: Nissan SR20DET

Hose Construction: Stainless braided with black Nomex cover, Kevlar reinforced

Weight: Up to 45 percent lighter than conventional racing hose

Fittings: Aircraft-grade

Crush Washers: New aluminum, included

Ball Bearing Turbo Requirement: Separate oil restrictor required (IS-OR-3036) - NOT included

S13 Top-Mount Variant: IS-T25-NS13-EXT

S14 Bottom-Mount Variant: IS-T25-NS14

S14 Top-Mount Variant: IS-T25-NS14-EXT

Sold: Complete line set with fittings and washers

Legality: Off-road and competition use only