65 Sportvan carb setup

Hello,

I bought a 1965 Sportvan earlier this month and I love it. Been doing a little bit here and there (Donivan walked me through diagnosing wiring issues and a bad alternator). I'm wondering what some things are in relation to the air intake of the carb, and what motor I have. I read somewhere the blue motors didn't start until early 70's, I don't see any evidence of orange paint underneath. I am seriously doubting this is the original motor.

Here are my questions so far:


What is this bracket for? Haven't seen that in other people's pictures.



What is the second hose coming off the can that is blocked off? Also have not seen this in all the image searches of inline sixes with my type of air cleaner.






What engine do I have - 230 or 250?

Here are the numbers on it:

Block 3850817
Below the big "GM" is a square with an M in it, and next to that a 2


Intake manifold numbers:
3859381
GM 18

Don,

I saw a post from you last night where you list the three different types of carbs - a Carter and two Rochesters - but I can't find it now. Which do you have in that picture? So maybe someone swapped out my carb but tried to keep using the air cleaner set-up? That extra blocked hose on mine, and that mystery bracket make me wonder if it is from a van at all. Do the engine block numbers mean anything to you?

Thanks

Found this on http://www.classictruckshop.com/gm_I6_casting_numbers.php

3850817 Chevrolet 62-78 230-250 - doesn't exactly narrow it down too much, but at least now I know it's not from a Buick!

It's a Sorttawerks carb, got it on sale at K-Mart! At least the darn thing fires up and drives. Supposedly the previous owner had a carb kit put on it but whoever did it, IF they really did it, didn't even clean it up well, it doesn't look like it was rebuilt by a pro. And it smells very gassy. Sometimes when I drive it I smells when I shut it down, other times not. Sumpthin ain't right. I think I'll start looking on the web for one of the three stock models instead of messing with this carb, and then start troubleshooting the lines even though they all look good. The reason I posted the pics and asked about the bracket and extra hose was to see if I have anything missing or run wrong.

Any recommendations on which one I should look for?