Messing in garage this snowy day I came across this carb.The base holes were elongated for variuos intakes, but I don't reaally know what year it may be. It's larger then some 1bbl so I'm thinking it's a later model from 60-70's.The only number on it is 7003536.It's been rebuilt,but has no tag. Any ideas as to year?

I will guess late 50's to 60's era.

MBHD

I think the large diameter air horn was after '57, not sure when they started using the side inlet.
I'm pretty sure it's a 60's carb.

Have you called any parts stores with that number?
Have you tried calling a Chevy dealership parts counter?

The 7003536 is the bowl casting number and was used on Rochester's in the 50's and 60's. Gearhead is correct that they switched to that type of air horn in 57 to "facilitate lower hood styling". So you have a 57-62 Rochester BC for a 235.
Z

Z33,Thanks for that helpful info.In case anyone wonders why I have a carb I knew not much about,it came in a box of Rochesters I bought at a local swap meet at the end of the day a couple of years ago. The seller didn't want to lug them back home.I've got 6 more, but this one was in the best condition. I paid 20 bucks for the lot. Now ,if I can find a bunch of Carters too!

It sure is clean. Are you sure its a carburator?