Jay Wire Solutions
Heater Bypass Blockoff
Heater Bypass Blockoff
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LS Water Pump Heater Bypass Blockoff – Thermostat Replacement
The heater bypass blockoff is designed to replace the thermostat in an OE-style LS water pump, helping you optimize coolant flow in high-performance or custom cooling systems.
When paired with properly routed heater core lines, this blockoff prioritizes suction of cool water from the radiator and directs coolant flow back to the radiator—helping you maintain more stable and consistent engine temps, especially in racing or high-load conditions.
Note: Gasket not included, but available separately.
Learn more about how this system works: ➡️ Watch the video
Product Details
- Application: Replaces thermostat in OE LS water pumps
- Function: Prioritizes radiator-to-engine coolant flow
- Cooling Benefit: Promotes stable temps by ensuring cooled water from radiator reaches engine
- Use Case: Ideal for racing, custom cooling systems, or heater core line deletes
- Gasket: Not included (optional add-on)
- Installation: Simple drop-in replacement for thermostat
- Educational Video: YouTube overview
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Exactly what I needed and shipped very quickly.
Is it some sophisticated technology? No, but it functions exactly the way it’s supposed to and doesn’t cost a fortune. Save yourself the time and money and just buy a JayWire product.
Great parts
fit perfect
I was having issues with water temps in the LS in my Drag and Drive car. I was talking to a buddy of mine and he reminded me of a discussion we had with some guys that we pitted next to during Sick Week 2024 in which they explained a fix they came up with for their LS Nova. I ordered a block off plate and my temps went from 195+ degrees to 160 degrees. Thanks for the help Jay.
Put it in my LS swapped Fox that had issues staying cool. Gotta remember to block off the heater core and not loop it. More people should know about this.