Stan Used Simple Solenoids in 1 ,2 &3 Rail Configuration
these are readily available . Along with ECU the Technology of recycling exhaust gas is
in place on all current combustion vehicles

The  EGR   Exhaust gate Re cycler solenoids are attached  
I have attached erg valves and exhaust coolers which should cover 90% of applications and
can be easy modified. All item off the shelf global basis

the key is knowing , once you know its easy!

Attached are some examples

Easy to find these basic on off fast solenoid in lpg applications or conversion kits
we recommended using a hydrogen injector for cylinder injection but for all other point
the attached example work fine for mixing or timing control applications

http://www.mechanicalengineeringblog.com/tag/dual-fuel-system/

Dan
www.securesupplies.biz

Seams Air horn parts can work they have rating up to 20 bar  which is crazy high
https://bit.ly/3aOB5sb

100% Brand new and high quality
Perfect for Air Horns & Air Ride Systems
Works on both 12 V Systems
Includes a 1/4" BARB fitting for 1/4" ID Hose
Suitable for car, train, truck
Material: All metal
Power: 12V


Package Include:
1 x Air Horn Solenoid Valve