Mega Boost Limiter Valve

What a Boost Limiter Valve (BLV) is: A BLV is an adjustable spring-loaded valve that only opens to release boost pressure when an over-boost condition exists. It requires no wiring, operates independently of all other systems, and adds both safety and performance to the supercharger installation.

Adds Safety: Our new Boost Limiter Valve (BLV) increases your engine safety in several ways. With a BLV installed, you can set your max boost level to match the maximum fuel delivery you have and prevent a dangerous lean condition during those moments of high boost and load - which will damage an expensive engine in just seconds! Plus, it can protect you from a missed shift or over-revved motor that can spike boost pressures and blow inlet tubes or damage MAF and MAP sensors.

Adds Performance: Imagine your centrifugal supercharger comes in now at 3500 rpm and your red-line is 6500 rpm. That's 3000 rpm's of usable boost. But now, with a BLV installed, you could change your drive pulleys to bring the boost in at 2500 rpm and simply bleed-off the over-boost at the top end. Now you have 4000 rpm's of usable boost!

Controls Boost Creep on Turbo Installs: If your turbo install suffers from boost creep, the addition of a boost limiter valve in your intake tubing can bleed off that excess and save you from a dangerous over-boost or lean condition. Our BLV can be adjusted to open anywhere from 6 to 30 psi!

Description: Expertly machined from 6061 aluminum billet, with a type 302 stainless steel spring, and a high-temp solid PTFE valve ball. A high-quality piece that will last for many years. Operating temperature range is -328° to +500° F. Has 7 large outlets - the Mega-BLV moves more than 4x more air than our previous 1" BLV. Can be polished.

Soft-Open, Soft-Close: Our BLV will not shock your supercharger system with instant pressure drops like a waste-gate does. Instead, our BLV opens slowly and gradually, just as much as needed, and closes the same way - preventing shocking pressure fluctuations that crack aluminum fittings and make smooth fuel map tuning impossible.

Capacities: When fitted to a supercharger that produces 1000 CFM on an engine with 15 psi of boost back-pressure, our new BLV has enough flow that it can dump all but 1.9 psi of what is in the system. In other words, at its maximum setting, it could reduce that 15 psi to under 2 psi (0.1 bar).

On a 1200 CFM supercharger, also producing 15 psi of boost in the tubing, our Mega-BLV can drop that tube to about 2.7 psi (0.18 bar) at max adjustment.

On a 1500 CFM supercharger, producing 15 psi in the tubing, the Mega-BLV can drop the pressure in that tube to about 3.6 psi (0.25 bar) at max adjustment.

Dimensions: Our new Mega-BLV will be 4.0" to 5.5" long (depending on how it is adjusted); and is 2.25" wide at the body. The ID of the weld-bung provided is 1.5" NPT.

Pre-Calibrated: When you order, you can tell us what to set the initial calibration to and we will set the BLV to that PSI for you before it ships. The BLV can be easily adjusted at anytime. No special tools required.

Installation: Simply install in any tube between the supercharger and the MAF or MAP sensor. Usually installed near the BOV. Choose from a steel or aluminum weld bung when ordering. One weld bung is included with your BLV at no charge.


To see all of our Replacement Superchargers Parts and Pulleys, Click Here

To see all of our Supercharger Rebuild Services, Click Here

Other Parts and Services from 928 Motorsports
Item Initial Adjustment Weld Bung Type Part Number Price (USD) Shipping* Availability
Mega Boost Limiter Valve U.S. Only: $15.00
All Others:
In Stock!   Typically Ships Same Day!

* Domestic US shipping shown. International shipping will be calculated based on location.