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Overheating, street Mustang '65 with a 331 Stroker

4K views 12 replies 9 participants last post by  blkfrd 
#1 ·
Hi,

I have a 1965 Mustang with a 331 Ford Stroker engine with overhetaing problems after an hour or so of driving time.
Set up is a 2 row, alluminum radiator with an thermoelectric fan which I believe is kind of small.
Has anybody had any overheating problem after getting a stroker engine ?
What is the best cooling set up I can have.??

Should I use a fan clutch set up with a 3 or 4 row radiator ?
Should I use the stock set up with a 3 or 4 row radiator with shroud and a flex fan ?
Should I use a similar current thermoelectric set up with the bigest fan for more CFM's,? how big/powerful can I go ?
Which one is the most efficient set up to avoid overheating ??

Any other suggestions ???

Thank you
 
#2 · (Edited)
When is it overheating? At idle or around-town cruising or highway speeds? Overheating at idle or low speeds typically means airflow problems. At highway speeds usually means flow issues.

Do you have underdrive pulleys? They'll slow your water pump down and cause issues sometimes.

With my 347, I eventually went to a 24" radiator with a dual fan Ford Contour setup. Works pretty good. But there are plenty of people that have the stock width radiator and it works just fine. Definitely need a good shroud and a properly sized fan whether you go with a belt driven fan or electric.

Also, a good 2 x 1" inch core radiator should work just fine. The larger cores give you more surface area and thus better cooling than a 3 or 4 core radiator.

-Shannon
 
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#4 ·
Hi, thank you for your responses.

Overheats in around-town cruising (stop lights and so), also at slow speeds in long traffic jams (40-60 minutes) I have to pull over and wait for the temperature to come down.
No underdrive pulleys.
OK, I will start playing with a shroud, a 4 row radiator and a belt driven good sized fan to begin with and because is what I have on hand right now.... I hope to solve the problem right then, otherwise I will go into bigger size 2 row radiator.
I will let you know; thanks once again for your help, both of you.
 
#7 ·
Somebody tossed me the electric fan when I was getting the drivetrain in. But now that I look at it looks kinda small and also appears to be weak. I will have a brand new 6 blade flex fan, a shroud and a brand new alluminum 4 row radiator and will see if that solves the problem.
 
#9 ·
I've got a 450hp 331 in my '65 coupe.. I run an ACP 2 core rad with a fabricated shroud and SPAL fan (the biggest one that will fit) thats controlled by the holley sniper. We creeped up the hill at power tour in 90 degree weather with the AC on and it was fine.

The fan you have is obviously not pulling enough air. Good luck with the manual fans! Hopefully that'll fix it for you, and if not, find a SPAL ion the right CFM rating.
 
#10 ·
I agree that this situation sounds like a fan issue. I only really trust the ratings on SPAL fans. A shroud of course would help but a 16" fan directly on a 16" radiator should also be fine.
 
#11 ·
I installed a Hayden 2710 fan clutch and Derale 17117 fan. It blows like a hurricane under the hood.

The clutch has a 3/4" pilot hole. Most water pumps have a 5/8" pilot hole. There should be a sleeve included with the clutch but there isnt. If you call Hayden they will send you one. In my case the replacement WP also had a 3/4" pilot hole so I used a HF step bit and enlarged the pulley pilot hole to 3/4".
 
#12 ·
My 69 351 is bored & stroked to 414ci. I'm running a 3 row 24" aluminum radiator. My engine came factory with a 5 blade flex fan, no clutch and I am still running it that way. I am also still running the factory fan shroud. the car has power steering and A/C and Auto Trans with the radiator trans cooler. I have a 160 deg thermostat installed. I am also running Evans Waterless, mostly because of the corrosion to the aluminum intake.

My engine does take a little time to warm up. For the most part, my engine always runs cool when driving. It has gotten up to about 210 deg when in traffic with the A/C on, but its a slow climb and when I turn the A/C off, it drops down quickly.
 
#13 ·
I cannot overheat my 331 even on the track on 95+ degree days. It's equipped with a 2 row Northern aluminum radiator, standard water pump, The 4 inch Mustangs Unlimited fan shroud and a 5 blade flex fan. I've been at the track on hot days going around and around with the temp being well under control while several guys in expensive cars are coming off the track because of overheating problems. Fan should be about 1/2 way in the shroud. My flex fan was NOS from the 80s when I bought it but never installed it until 2004 during the resto...glad I kept it.
 
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