I have a 250 inline 6 in my old GMC and I would like to put a turbo on it. I know a guy that ran a .52/.60 turbo but he said it was too big and only built boost at 2500 rpms.

My engine is stock and I'm not looking for a ton of power or to run a lot of boost ...

Anyone have a size suggestion?

 

find a used grand national turbo.

 

check this out

 

Yes I have watched this and thought about trying this model turbo. Was just wondered if it would spool at slow rpms. They used a .70/.63 turbo

 

I think you might be expecting the wrong thing from a turbo. If you want instant boost you need to be looking at something belt driven. Is this vehicle manual or automatic? How much power are you looking to make? How do you plan to use it?

Spooling by 2500 RPM on a gas engine is pretty good, even a low revving old I6. Since you are probably pushing 2500 RPM at 50 MPH you are already in a zone where you are going to boost on the slightest hill while cruising around. You also need to think about the extra load on the bottom end, especially at lower rpms.

 

Ok this sounds fine. It's a 4 speed manual not looking to make a lot just play around a little bit. Just a toy.