I have a 1987 engine that came stock with the 350 TBI in a Suburban. I want to put this engine in my 1962 Impala and use a carburetor rather than do all of the work involved in converting the IMP to fuel injection and moving the computer.
I understand that the 87-95 heads need a different intake than the older Gen 1 heads and I was wondering why. These are non-vortec heads. Do they have differences other than the bolt angles? I have heard that the intake port was higher in these heads as a precursor to the vortec heads but do not know if this is so. I have an older set of heads and intake to use on the engine if the only difference is the bolt angle. However, if they are better heads I would spring for the new intake to keep them. I will admit that this is the strongest stock 350 I have ever owned. It is also the latest model 350 I have ever owned. If the heads are the difference I want to keep them.
Thanks for the help.  

The 87-95 heads altered the angle of the center intake manifold bolts whereas the Vortec design changed the manifold bolt pattern (I believed added a bolt).

I don't think that the intake port location has been changed very drastically, you could check the alignment with some dye if you go with a dual plane.

I'm afraid that your heads may be of the 'swirl-port' design, which is absolutely horrible for top-end power production. If you're looking for a cruise engine to get decent mileage and only make 300 horsepower then they may be usable but otherwise they were a bit of a fluke. They also have a smaller chamber than late-model heads and have a larger dish in the stock piston top. So, if you put these heads on flat top pistons in an old Gen I engine you may have an excessive compression issue. I'm unsure of the exact volume (and you didn't give a casting number) but from memory I recall them to be significantly less than the old standard (76 cc).  

Probably the compression and the TBI make it perform better since the Compression is around 9.5 to 1.
Heads should be about 64cc

Summitracing.com has a very nice online selection of manifolds for those heads that will use a carburetor. Just search “intake manifolds” then select your make and model if will have a complete list of ones that would work. You can also call them and they will tell you what is available.

I do not know if the heads a any different  

Thanks folks. This was the type info I was after. Since I will be cruisin' this thing instead of racing I think I will just buy the intake and use a Road Demon that I have on the shelf. Again, thanks for the info.