Has anyone built a large volume air compressor?

[November X-ray]

Has anyone built a large volume air compressor? I've been tinkering with the thought of bolting two volkswagon air cooled motors together and running one on gas and building a set of heads on the other to compress air with. I only need about 50 to 60 PSIG but about 80 to 90 SCFM. I know commercial made units often run a V-8 type engine with a special head on one side to compress air and the normal water cooled head on the other side.

I planned on using swing type check valves that sit at a 45 degree angle for the suction and discharge valves, but the real question is will this need to be a dual stage setup and will it require water cooling on the compressor heads? I understand the technical issues and have made several 2 cylinder engines out of 4 cylinder VWs, but just wondering if there might be a better/easier way?

Thanks

 

[Highpower]

This is the only one I've ever seen, and I thought it was a stroke of genius!

Like you said - engine runs on one bank and other bank is the compressor. It's an air cooled engine anyway, so no need for coolant.
I would love to build one myself but don't have any place to store it!

 

[Tony Wells]

Couple of things jump out at me. Flapper/swing check valves aren't all that good for strong pulses. I've seen too many of them break. I'd recommend a disc or ball type.

Other thing is that since you are going for volume, you don't need to run them as a two stage. This will save you heat dissipation also since you will see lower pressure. Still within your specification, I'd say.

Way back in HS shop we did a Ford 302 air compressor for a local construction company. They used it to run a sandblaster. It was as you described, one bank for the engine, the other for the pump.