Can a water pump underdrive pulley cause my car to overheat??

[juiced_94gt]

Well ever since I bought my car 5 years ago it has ALWAYS ran hot im 90*+ weather here in cali, I have ver even thought about using the AC as it will run hot almost instantly, it has had mac underdrives on the entire time and even after the 331 rebuild whith an ENTIRE 100% cooling system with the fan programed to start at 180* LS and 190 HS with a 180* stat it still ran hot so I put the stock water pump pulley back on and am waiting for some hot weather to see if the smaller pulley will make a difference, what do you guy's think?

 

[Adam95GT]

Well ive heard of charging problems b4 and slight over heating issues... but its normally an underling problem

 

[earleys94gt]

I have not heard one of our cars running HOTTER with an underdrive water pump pulley. You would actually think with the pulley being underdriven, thus spinning faster, that it might cool a little better.

I've heard that our cars run hot as it is, and that is why some have swapped in diff. fans. That might be a solution...

Now that you have a 331, which would create more heat than a 302, and eventhough you have a new thremo., fan program, Fluidyne etc., you may need a slightly larger or more efficient fan. Just my 0.02...

 

[str8stang036]

I know its a problem I have with underdrive pullies. I will be switching to an electric pump for better efficiency. This is without a t-stat and fluidyne and fans.

 

[juiced_94gt]

I have not heard one of our cars running HOTTER with an underdrive water pump pulley. You would actually think with the pulley being underdriven, thus spinning faster, that it might cool a little better.

I've heard that our cars run hot as it is, and that is why some have swapped in diff. fans. That might be a solution...

Now that you have a 331, which would create more heat than a 302, and eventhough you have a new thremo., fan program, Fluidyne etc., you may need a slightly larger or more efficient fan. Just my 0.02...

When you buy underdrives, the crank is smaller but but the WP pulley is 1.5" bigger than stock, not sure if that would cause issues...Would spal dual 11" fans be an upgrade to the stock unit? that is what I have been looking at.

 

[HISSIN50]

I would consider the fan upgrade only if you run cool enough at highway speed but heat up once sitting in traffic.

I'd consider overdriving the water pump (IIRC, a fox cobra pulley overdrives our pump. Check on that before purchasing or doing).

 

[95Vert383AOD]

Get a Lincoln Mark VIII fan. Gotta clearance it a lil but its the biggest highest flowing fan that uses the factory fan plug. It flows more CFM's than many aftermarket fans. Only thing is i believe it uses about 40+ amps. When i turn my car off i can hear it spinning down.

Chris

 

[HISSIN50]

Chris, do you have pics of your Mark VIII fan? It must be a tight fit, even if you tucked your radiator under the radiator support.