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Stop Oil Burning and Restore Compression With Precision Manganese Bronze Valve Guides
Worn factory valve guides let oil creep past the stems and allow the valves themselves to wander off-center, robbing your KA24DE of compression and clean combustion. The Supertech GDE-NKA24-7-EI-OS-8 set replaces all 8 intake and exhaust guides with precision-machined manganese bronze guides engineered for consistent oil control and accurate valve seating on rebuilds, head refreshes, and performance builds alike.
Key Features
- Full set of 8 guides (4 intake, 4 exhaust) covers a complete KA24DE cylinder head
- High quality manganese bronze construction for excellent wear resistance and heat dissipation
- Oversize (+0.02mm) fit for reboring worn factory guide bores during a head rebuild
- Engineered to pair with Supertech low friction black nitride valves for reduced stem wear
- Precision-held tolerances for accurate valve seating and consistent oil control
- Direct fit for GDE-NKA24-7-EI-OS-8 machining specifications, no modification required
Fitment
| Year Range | Make | Model |
|---|---|---|
| 1991-1998 | Nissan | 240SX |
| 2000-2004 | Nissan | Xterra |
| 1998-2004 | Nissan | Frontier |
Specifications
| Detail | Value |
|---|---|
| Manufacturer Part Number | GDE-NKA24-7-EI-OS-8 |
| Brand | Supertech |
| Engine Application | Nissan KA24DE DOHC 16v 2.4L |
| Guide Material | Manganese Bronze |
| Outer Diameter | 11.03mm (+0.02mm oversize) |
| Length | 39.6mm |
| Quantity | Set of 8 (4 intake, 4 exhaust) |
| Condition | New |
| UPC | Not assigned by manufacturer |
What's Included
- 4 intake valve guides
- 4 exhaust valve guides
- Manufacturer packaging
About Supertech
Supertech Performance specializes in precision valvetrain components for racing and street performance engines, including valves, springs, retainers, and guides machined to tight tolerances for durability under sustained high-RPM use. Their manganese bronze guides are a common choice for engine builders looking to correct worn factory bores during a head rebuild.
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FAQ
What is the GDE-NKA24-7-EI-OS-8?The GDE-NKA24-7-EI-OS-8 is a set of 8 manganese bronze intake and exhaust valve guides sized for the Nissan KA24DE 2.4L DOHC engine, cut to a +0.02mm oversize for rebuilding worn factory guide bores.
Which vehicles use the KA24DE engine?The KA24DE 2.4L DOHC engine was used in the 1991-1998 Nissan 240SX, the 2000-2004 Nissan Xterra, and the 1998-2004 Nissan Frontier.
Why are these guides oversize instead of stock size?The +0.02mm oversize accounts for the small amount of material removed when reaming out a worn or damaged factory guide bore, so the guide seats with proper interference fit after machining.
Can I install these guides myself at home?No. Valve guide replacement requires pressing out the old guides, reaming the head bore to the correct oversize dimension, and pressing in the new guides with a machine shop press and precision reamers. This is a machine shop job, not a driveway repair.
Do I need new valves with this valve guide set?Not strictly, but Supertech designs these guides to pair with their own low friction black nitride valves for the best combination of oil control and reduced stem wear. Reusing worn factory valves against new guides can shorten the life of the guides.
Are these guides for intake only, exhaust only, or both?This set includes both, 4 intake and 4 exhaust guides, enough for a complete KA24DE cylinder head.
What material are these valve guides made from?Manganese bronze, chosen for its wear resistance and heat dissipation properties compared to cast iron factory guides.
Will this fit a KA24E SOHC engine?No. This guide set is machined specifically for the KA24DE DOHC 16-valve head. The earlier KA24E SOHC engine uses a different valve guide configuration.
Install Instructions
- Remove the cylinder head and fully disassemble the valvetrain
- Press out the worn factory valve guides using a machine shop press
- Ream the guide bores to the correct oversize dimension for a proper interference fit
- Press in the new Supertech manganese bronze guides squarely and to the correct depth
- Ream or hone the new guides to final bore size for correct valve stem clearance
- Re-cut valve seats as needed and reassemble the valvetrain with new seals
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