Blair G said:
Looking at yours looks like it would a perfect solution to what I have. I need to look at the donaldson website. The previous owner installed the prefilter when he rebuilt the motor in Australia as the dust killed his last motor.
Donaldson Top Spin prefilter # H002437
Takes a 3" pipe. The body diameter is 6.4 inches & it is 5-3/4 inches tall including the pipe clamp at the base.
The unit is self cleaning so it will not collect dust for you to empty out.
Operating flow range is 90-200 cfm so it works with my 302 V8 up to around 3000 RPM without restricting flow I only cross 3000 RPM when trying to accelerate quickly.
A chevy 350 should probably go one size larger, a # H002425 Its operating flow range is 200-450 CFM. That means the precleaner might not work properly below 2000ish RPM.
Here's some quotes:
"The Donaldson TopSpin pre-cleaner has the lowest restriction of any competitive brands tested, including our own full-view pre-cleaner."
"Separates up to 85% of incoming contaminant (per ISO 5011/SAE J726)
Greatly extends air filter life
Reduces air filter usage
Lowers cost per operating hour
Automatically ejects mixed debris
Separates more than 99% of particles 20 micron and larger"