Ever hear of one of these? Guy claims he made 11 psi boost on a 6.2L with this.

Rayjay made all kinds of aftermarket bolt on kits for corvairs to 3208 cats to farm tractor conversions. They sold out to Rotomaster which then sold out to AirResearch, who then sold out to Garrett. Parts might be a little hard to get, but they where robust and quite compact. One feature that set them apart was the turbine shaft was one piece inconol. Extremly high heat and wear resistant. Most if not all turbos today use flywheel fussion to weld the inconol wheel to the standard steel shaft. (The shaft is actually two pieces).

Went to a Rotomaster dealer meeting and the head CEO said they where getting out of the aftermarket retrofitting. Two months later they buy Rajay which specialized in it. Before they went belly up they sold alot of their aftermarket kits and components to the dealers at a substanial savings, with a no return policy attached.

The Rayjay would spool up quite fast due to the lower rotating mass.

I'd stay away from buying one of those. You need something in which you can tune with different exhaust housing AR's

The one pictured looks like it has a Rotomaster tag.

Tried a similar one once off of a JD tractor. It made similar boost, but was somewhat laggy like any non-wastgated turbo.

Sounds like it would be similiar to the bigger pinisular turbo DP has. A little propane might wake it up. worst case senerio, I know a 6.2L owner who mentions getting a turbo every time I see him.

I ran a rajay turbo for about 500,000 miles on several 6.2's up to and including my last 6.5. I used to get 12 to 13 psi on my 6.2's and well over 22 on my last 6.5 18:1. When I sold that 6.5 I had to put in a new cartridge because I got a little overzealous one morning when it was -30F and didn't let the engine warm up enough before getting on it.:( Overall turbo performed well and US diesel parts in MT. was able to get me a new turbo and a cartridge on different occassions.
The Rajay was part of a complet 6.2 kit that I purchased from a company called turbo engineering back in about 1990. They marketed the kit as a magnum kit and claimed it outperformed everyone else's kits at the time and I would agree by the way it ran.
If I was going to build something now, I would probably run a HX 35 and adjust the wastegate down to limit max boost.:cool2:

Would you buy it for $75 if you had a 6.5L with a gm-4, I'd think yes.