I just bought a engine that I'm almost certain is a 400, but from looking on the the resources page it seems to indicate its a 350.
The casting number is 3951511 which from my understanding indicates it is a 400.

The engine number is T0701CGR, whuch if I am reading the resources page right indicates its a 1971 350, 330 HP?

The bore measures 4 1/18 inches, which is 400, and has 4 bolt mains.

The casting on the heads is 3951598

The VIN is 10J285311

I am intending to do a mild build on this and replace my 350 thats in my 69 malibu

Any help or direction with any of the above that anybody could provide would be appreciated

CGR is also 70 Impala 400/265 LF-6 2bl.
Partial vin:
1=Chevrolet div.
0=70 model year
J=Janesville assembly plant
285311=car sequence number
Those are the correct heads for that car.

Check this page it has the correct info
http://www.nastyz28.com/decode.html

Mortec.com lists the block as a 70-73 400. Head casting says 70 400 as well. I don't find a CGR suffix for a Chevelle so I can't confirm and from the VIN derivative, it looks like some other model of Chevrolet but the 2nd digit of "0" seems to indicate 1970 was the donor car's year. Also "J" isn't a Chevelle assembly plant, so it'd probably be another Chevrolet model. There are 2 400 small blocks for 70 Chevelles (not listed here on TC) of CRH and CZX - the 71 400 Chevelles are CAJ and CLK. The 70 is rated at 265hp and the 71 at 255hp. Trans type is the difference in the suffix code for each year.

What reference did you use to find a 71 330hp 350? I show ratings on 71 350s to be 245hp and 270hp and the 70 350s to be 250hp and 300hp.

Someone will jump in here before long to help with the VIN derivative.

See - beat me to it as I was typing this out. :D

I was looking at www.chevelles.com/years/71/71codes.htm (http://www.chevelles.com/years/71/71codes.htm) which listed a CGR as 350, 330 HP, but since this didnt come out of a Chevelle maybe that isn't applicable? Sounds like it must have come from an Impala. The other thing I have noticed is that the heads have 2 triangluar markings on them in lieu of double humps, any idea what those markings represent?