carb and fan questions

[Zorm]

Hey all,
would there be any gain by replacing my old 66 1bbl carb with a newer 1bbl carb off a 250 out of a 70's Ford, would the newer one bolt up to the older head?

Also, the rad fan, has anyone tried to remove the old mech fan and replace with a electric fan? I did a Taurs electric fan swap on my two Jeeps with inlines and they work great.

 

[Anlushac11]

You can gain a boost in performance by switching to a YF carb off a Ford 300 I6 truck.

IMHO the newer 250 I6 will have a Holley 1946 carb, I think its easier to tune and get parts for.

Opinions here are split over nechanical and electric fans. I personally like electric fans since they dont consume as much energy to turn as a belt driven fan.

 

[CZLN6]

Howdy Zorm:

Your '66 200 Autolite 1100 has a rated flow of 185 cfm. It also has a Spark Control Valve (SCV) to send a specific vacuum signal to the stock OEM '66 Load-a-Matic distributor. If you were to change to the '70 250 Carter RBS you will gain additional cfm as it is rated at 215 cfm, but it has no SCV so is not compatible with your Load-a-Matic, vacuum only, distributor.

IF you could get both the '70 RBS carb and distributor, you'd have a nice coordinated upgrade. The carb has a ported vacuum port which is what the '70 distributor needs. The '70 distributor will have both vacuum and centrifugal advance- another improvement.

The '70 RBS carb is actuated by a cable linkage and has a larger diameter throttle bore, so some modifications and adapting would be required. It would be a worthwhile upgrade for your '66.

Adios, David

 

[Zorm]

ok, so how about the carb from a 300 (will it be a direct bolt onto the log manifold?) with the Duraspark II dizzy?

 

[CZLN6]

Howdy Back:

No, the YF from a 300 will not be a direct bolt-on. Also it is jetted and designed for a much larger displacement engine and different driving characteristics. I seem to recall, it is rated at 220 cfm, so there isn't much gain over the much simplier and shorter RBS. It can be made to work, but not easily. Do a search of Mustang Geezer's posts. He's been down that road.

The DuraSpark II ignition system is compatible with either the Carter RBS or the YF from a 300. It is an even better system than the '70 distributor mentioned earlier.

Adios, David