Have a 440 in my Coronet with a mechanical fuel pump,don't like seeing the filter in the engine compartment,can I put the filter before the pump?any drawbacks doing it this way?

Yes there is! If you put filter before the pump, your carb is NOT protected from possible particles FROM the pump. On my 383, this is how I did it. Pump...short(fuel rated)hose turned up...steel filter(vertical)...more hose(still vertical)...into end of steel line which goes vertical alittle more before turning towards the carb. This filter location is in the air flow from the cooling fan which I think help cool it, too. (The sock on the end of the fuel sending unit in the tank is suppose to protect the pump)

Haven't got that far in putting mine back in my challenger, but I'm almost certain it goes before the pump. I will probably to so whether it was or not. Why run crud that makes it through the pick-up strainer through the pump first?? On my 74 B100 it was under the vehicle quit a ways before the pump. I have even heard of running more than one inline filters. Can't have too-clean fuel The more I think about it, it seems, after the pump puts it right close to the engine. That doesn't sound good....

Edit: Plymies was posting as I was typing and makes a valid point. Still, no reason you can't have one before AND after

My 79 B300 has the filter under the van, way before the pump. No problems in the last six years (although I do have a new one in the van, just in case).

Carbureted vehicles generally have the filter after the pump.

I tried the "before" and "after" filters in '70 Sport Satellite 383. Not long after and I had trouble with vapor locking. Removed the "before" and trouble went away. Coincidence, I don't know. No vapor locking for years.

Why car companies place the final fuel filter after the mechanical pump?

1. Mechanical pumps have more trouble overcoming restrictions on the suction side compared to the pressure side.

2. A restriction on the suction side can create a low pressure area. Volatile liquids like gasoline and ethenol are more likely to vaporize as the pressure drops.

3. The primary function of the filter is to protect the carburator. Carbs have very tiny passages and orafices.

Tip: Install filter with the outlet at least somewhat higher than the inlet. This help lets the vapor out. You could see this with a clear glass filter. The car companies knew what they were doing. They may not have always got it perfect, but give 'em credit for having a reason and often a lot of testing and experience behind most every decision.
If you have a later car with a vapor seperator, make sure the separator outlet is rotated to the 12 o'clock position.

As said: filters create a slight restriction (they have to to do their job) which can but not neccessarily cause vapor lock if used before the mech pump (E10 greatly aggravates this). Bottom line is you want to protect the carb and a filter before the pump protects the pump and the carb from the tank/rear line debris but not the carb from the pump debris which the pump debris (valve shredding) is way way less than what can come from the tank (gas station pumps kick out a surprising amt of crap) and a filter after the pump protects the carb from the tank and the pump but not the pump from the tank debris. Short answer: Put one before the pump if you like & if no vapor lock issues & the carb continues to idle well (idle passages are the smallest & get affected the worst/easiest from minute debris) then you're good. Do you feel lucky, well do ya

cellulose filters should never be put on the suction side of any fuel pump. some high micron screen filters will work but never a filter designed for the pressure side of a pump.