On my '70 442 I want to go to a 7 blade fan from the factory 4 blade. The car has a 3 core radiator with no air conditioning. Will I have to change the water pump to the longer unit? I think mine calls for the shorter unit.

 

No you shouldn't have to. The longer unit is for A/C equipped cars, not a difference in number of fan blades. Are you still using the fan shroud? That makes a world of difference.

 

I would recommend using the stock fan clutch if going to the 7-blade. The 7 blader will move a lot more air than the 4 blade. Without a clutch, it will put considerable strain on the water pump bearings, rob lots of HP at higher-than-idle engine speeds, and make a lot of noise. With a clutch, the fan only runs when the temperature requires it.
It should all bolt together fine as long as the water pump has the same hole pattern.

 

You can't even bolt the 7 blade fan up without a fan clutch anyway.

 

I have the same setup four blade fane no clutch on my 67.

I guess I would have to get a clutch either way(if I was to get a 7 blade fan or improve what I have) it was sugested by club members.Though I had several tell me put a electric fan in.I don't know if i want to do that as the car is stock origional and changing too much would make it a modified class car.

 

Switched out my 4 blade to a 7 blade w/clutch and 3 core because of overheating. Actually, did the rad first (was a 2-core) because it was running hot and spitting up all the time. The 3-core upgrade alone didn't help, but doing the fan did the job! Drove the car 1000mi round trip to the Nats and not one issue! My car ('65 Vista) doesn't have AC so, no shroud!

 

What prompted my original post is one of the major West Coast vendors states that the 7 blade fan: "Fits engines with a long water pump." That would indicate to me that it will not fit my short water pump, which I have because the car did not have A/C. Looking at fan clutches it seems there are too many choices (e.g., reproduction, original delco, Flex-a-lite). One of the other vendors lists ones with three with different diamators. What do you recommend? If I put a fan shroud on my 70 442, which did not come with one, will I have to make alterations, or is it a direct fit?

 

As for a clutch, I would go with just a stock-type unit, available at the local parts house or through Fusick. I used one from the parts place, but as with most of their stuff, it required a little modification to get it to fit and function right.

For the shroud, get one for your year and model. If there is not one for 442, then get a Cutlass one. You would need the U-nuts and screws, but the holes should be there. It ~should~ bolt on.

 

There are spacers for a clutch and to replace the clutch ...

They can move the fan closer to the radiator ...

 

I understand your hesitation then. That would have to mean the fan blades have more curvature in them or somehow their shape is larger so that they would interfere with the water pump I guess. Unless that statement was a re-assurance that the fan will not interfere with the radiator when used on a long shaft pump. Could you call them and ask?

 

The factory set up for 1970 with HD cooling is a 4 core radiator, shroud, and a 6 blade thermoststic fan.

Where does the 7 blade fan fit in?