Mailbu Beach

Frankie the Fink

For the 57 year the info I have says they are interchangeable, so I don't know that there is a significant difference...

Mailbu Beach

L78racer

245 and 270 hp all have those main bodies. 270 hp main bodies differ but are same number(s).

Frankie the Fink

And if its a very early 57, they used 56 carbs and only the 049 bodies...
The '56 carbs have the idle air bypass screw in the base as shown...

tgtexas02

Thinking all 0-049 and 0-1049 are the same and according to 58-60 Tech Info Manual & Judging Guide-both are correct. The only difference I know of between the 245 and 270 main bodies would be the counter weights and the main nozzle on the primary side. Not sure I really get this last part but the 270 you can look into the nozzle and on the 245 you cannot see the tube--I don't get this at all. On the air-horn, it may or may not be stamped ahead of "6-1299" casting with front "1161' or rear "1296". And, the prior to 61 front bases will not be tapped for vac.

Frankie the Fink

The 270 hp carb bodies have primary nozzles cut at a 45* angle as show in this picture in the green circles even though the 245 and 270 lid numbers are 6-1299 in both cases... The counterweights are smaller on the 270hp carb.so the rear air valves can move with the lower vacuum of the solid lifter engine...

I "think" I recall that the spring under the vacuumeter piston that rides off the bottom of the metering rod "T" bar had different tension for the same reason, but I haven't confirmed that...

The 61 bases for the RPO-242 PCV option had tapped bases, I don't know if non RPO carbs for the same year did or not...

tgtexas02

I get the angled nozzle on the 270 HP but I still don't get the "cannot see the tube" for 245 HP in NCRS guide. Basically, what do the tubes look like on a 245 HP setup? I have a set that has original "L8" brass tag date "2627S" which is 245 HP and the air-horn nozzles look just like the 270 HP.

Frankie the Fink

That's just a bad description I think..... I take it to mean that you can't look down into the straight, vertically cut off nozzles (tubes) as you can with the angle cut 270hp primaries. I wouldn't dwell on it. The NCRS documents are far from free of mistakes and vague statements...

Mailbu Beach

tgtexas02

You might also note that the 1299 rear is drilled for choke shaft while the 1299 front will not be drilled.