Running warm

[Stangman]

Going to be dropping my 485 into my 67 stang and have always had a problem with it running hot in traffic or in line at shows from reading the forums  I think a water pump pulley swap might be needed I have a cross flow rad Modine #430 and this last time around I got a aluminum radiator from griffin which didn't get me anything. I have duel 11 inch Jegs electric fans 180 thermostat . Now I have a 7 inch pulley on my new Romac balancer and a 7 1/4 water pump pulley was thinking about a 5.4 inch pulley from CVF do you think that's a good idea and I also dropped comp from 11.8 to 10.75 thinking that might cool it down a little and be a little more pump frindly I normally have timing all in  at 34 at 3000 don't know about my new combination yet

[Nightmist66]

Hi Stangman. What water pump are you currently using? Are your fans rated at 2760 cfm? What temp do the fans come on at? The smaller pulley would probably help, but will have a little more parasitic drag. It sounds like a flow problem of some kind. If it is only at slow speed/stops and low rpm, it sounds like the coolant flow is insufficient or airflow across the rad. is insufficient as well. Do you run a 50/50 mixture? Oh btw, what is the temp reading that you say is hot? Does the temp change any if you rev the engine any?

[Stangman]

I am using aluminum edelbrock and yes they are 2740 or 60another thing is I had the fans coming on at 180 /185 and supposedly that's not right they should come on more like 195 It seems the fans are alway on and the cucuit breaker I use has overheated and tripped and I have to let it cool down. Like I said the fans come on at 180 and it seems it just creeps up and up and after a whil it will get up to 225/230 and I have to pull over and let it cool down. Now if it's 75/80 degrees it will be ok maybe 210 but it's still not right. And it does it in traffic or a long ride then again I normally don't drive it to far for fear of overheating I have a lot of money into it and want to nip this problem

[Nightmist66]

It is true the fans need to come on at around 195 with that t-stat. That should not cause an overheat issue though. It's kinda like a mechanical fan that runs all the time, can't hurt. Kinda wierd it is overheating the circuit breaker though. Is the circuit breaker rated for enough current for that fan setup? Do you run a relay in the fan wiring? Do you have a sufficient power/ground for the fans? It probably does not have enough cfm for your setup. The 2700ish cfm sounds low, probably needs 3200-3500 cfm. Maybe someone else will add on the cfm rating.

[jayb]

It sounds like you have enough radiator to keep it cool.  A switch to a smaller pulley to turn the pump faster at low speeds could definitely provide an improvement, and for the cost it would be worth trying, I think.

I am skeptical about your electric fans.  Electric fan ratings from most manufacturers are in free air, with no restriction.  When you put the fans in front of a radiator, suddenly they don't flow anywhere near as much as as they are rated because they are trying to pull (or push) air through the radiator.  This is when you find out if you've got good electric fans or not.  My opinion is that the only electric fans out there worth buying are Spal fans, and I'm sure that's not what you have.  Spal is also the only manufacturer I know of who rates their fans at various pressure drops, so that you can get some idea of how much they will flow when they are put in front of a radiator.  I've solved several very difficult cooling problems by replacing DeRale or Flex-a-lite electric fans with Spals.

Also, if you are overloading the circuit breaker that runs your electric fans, you need to increase the wire size, circuit breaker size, or relay size, to eliminate that issue.  You might need a bigger alternator to provide the juice for the fans.

Try the pulley first, but if that doesn't solve the problem, I'd recommend a switch to Spal fans and the wiring/alternator upgrade, if required, to go with them.

[Stangman]

thanks Jay Iam going to get the pulleys because it cant hurt it can only help. the wiring for the fans was done a long time ago when I had two 10 inc fans with no shroud. when the fans come on I can feel the air being sucked in from the front of the radiator but I always thought it should be more . I ws wodering if the 16 inch fan from spal would be better than the two 11 inch ones and I geuss i will rewire with the kit from spal