IS the 616 a medium body or Large body MS carb?

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Thanks for all the replies.

I put a 1-1/16 venturi in and gained 10 cfms @ 10in-hg. What else needs to be done to feed a 267 ? The restriction seems to be the carb so far. The heads and intake manifold flow close to the same, with a slight edge to the intake (1cfm). The carb needs 10 more cfm to be equal to intake ports.[/quote]
If you have a lathe get a piece of 1.5 brass or aluminum stock and make a bigger one. 1.125 may put you where you want to be. Just try to approximate the shape and the internal taper of the original. Relieve the outside as there is a passage in the front that needs airflow from the rear for the idle circuit. I make straightwall venturis at 1.300 and there's room for a bit more but I modify the carb upper body so that passage can get air by another route.

mEl

The tsx 616 is a big body carb if I remember correctly. It should be the same size as the zenith modle used. Checking with the gaskets in a kit wont do much good because they include the small and large gasket in them because all the other components interchange. If your looking for more hp You can take a venturi for a U Moline and put in the 616 and get an extra 10 hp.

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JT, you wouldn't know the size of the U venturi would you? The 830's used a 1 1/16 venturi and that is what I use for a stock DC when converting them from the Zenith. For pulling I always felt the Zenith with the booster venturi was somewhat restrictive at higher rpms.

For bigger CID applications I make my own venturii which seem to work very well if the fuel circuits are modified to feed the extra airflow.

On what application were you getting 10 hp for a venturi change, that's interesting. 10 hp is a nice gain from a simple venturi change!

I know a DC likes a MS carb with a 1 1/16" venturi. A well setup MS gives a couple more hp but the engines idling characteristics are much improved.

The bodies with a bolt on inlet will bolt directly to a DC air cleaner if you want an original look.

mEl

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Thanks for all the replies.

I put a 1-1/16 venturi in and gained 10 cfms @ 10in-hg. What else needs to be done to feed a 267 ? The restriction seems to be the carb so far. The heads and intake manifold flow close to the same, with a slight edge to the intake (1cfm). The carb needs 10 more cfm to be equal to intake ports.

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I don't know specifically what body size that is but, the large carb as used on the 400 800 830 etc measures 1.437 at the bore for the butterfly. That is the carb I use for my more stock performance applications.
Motec engineering can answer your question if you do not have the carb apart to measure it.
mEl

I am sorry I can not tell you which size it is but you might try this to find out. Go to an auto parts store like O'Reilly's and if they have the kit on hand you can look at the gaskets in the kit to see if it is the big or medium size body carb. Just an idea for you so you can find out since no one has answered you