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stroker getting warm


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4:36 PM
Jul 27, 2018
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Severn Bridge
just got the new 440 stroker,alum head engine running and noticing it's getting very warm! the car was fitted with a new aluminium rad when it had the 318 with mechanical fan! it's now running an electric fan!
pretty sure all the air is purged out, any tips for sorting this out?
what stat temp is best?
What's "pretty warm"?

180* thermostat is the choice of many. Make sure the coolant is circulating. Use the least amount of antifreeze that you can for your area.

I hate electric fans, jmo
1. Dump the electric fans.
2. What is your timing.
3. Are you getting a tight seal with fan shroud?
Use the least amount of antifreeze that you can for your area.
I hate electric fans, jmo
Add a bottle of Water Wetter!
And new builds are "tight" and may build a little more heat during break in.
More info needed...what are the temps now? Compression/bore size/fuel? As was said, new engines run hotter for a time (not 'overheating' but warmer than normal). My first guess is the timing needs to be advanced more. Which cam is in it?
It always astounds me when someone posts wanting help when they find out their new horsepower monster has cooling issues. It's one of the most frequently asked questions on this forum.

Search FBBO and you will find out.

I'll see if I can find the link I posted to an article Don Armstrong with US Radiators wrote on cooling a Charger.
First question is : how big is your existing radiator . You said you had it when the engine was a 318 . If the car was mine I would look to put the largest one I could install in it . I put a 31x19 aluminum with 2 1 inch tubes . In order to fit this in my 65 car I measured and trimmed the inside edges to the frame where they fold over and tack welded the it back up . This small mod allows for the large one to drop in . The radiator I purchased has a full metal shroud covering the entire face of the radiator and has 2 12 inch spal fans attached . Each fan pulls 1340 cfm for a total of 2680 cfm . That's a lot of air being moved . I see that a lot of folks do not like electric fan . All of the new autos today have electric fans on them , including the Dodge Hellcats with 700 plus hp . I have a stroker Hemi in my car and feel that this rad and fans will work . I built a 1972 Dodge Colt years ago with a blown 440 in it , I fought heating problem until I changed out the radiator to a lager one with electric fans , worked out better heating issues were gone . Just my thoughts . Thanks John

P.S. I will use the Spal relays that match the fans and run them with a manual switch . Hope this helps John

where are you?
I like fan clutches and matching fan with as many blades as possible
shroud is essential
you can use electric fans as a pusher with the ac or stop and go traffic
(provide cold air for the air cleaner)
seal all the holes in the core support
run a spoiler/ valance

do you have a real temp gauges?
check your oil temp
6 quart or aftermarket pan and cooler will help
you can run half inch trans cooler lines to a 100 plate and fin cooler with half inch in and out and eliminate the heat in the in-radiator trans cooler (depending on where your are)
Redline makes water wetter
how many lb thermostat
are you boiling over- loosing coolant?
There's a lot of variables in an over heating question.
you guys have lots of information and yes we just slammed this motor in without any upgrades to cooling other than the electric fans we had already!
I'm just picking brains to see who's done what and had success!I know I haven't given much info as to motor details. the thing I'm most impressed with is my sons home made bellhousing for the ZF. thanks for all the input and the links were informative!
Well, the car hit the street today for a quick lets see how it feels, and it's a beast! lots of little finishing touchs to do [cooling mods,more wet sanding,throttle hanging a bit retuning to full idle but the motor/trans combo works and the test run was to try to decide what rear gear will work! I'm hoping the car will be finished in a couple weeks and I'll post lots of pics. and video!
pic when motor was dropped in

just got the new 440 stroker,alum head engine running and noticing it's getting very warm! the car was fitted with a new aluminium rad when it had the 318 with mechanical fan! it's now running an electric fan!
pretty sure all the air is purged out, any tips for sorting this out?
what stat temp is best?
If upgrades are in your budget or necessary go with the biggest aluminum radiator that will fit. Run an electric water pump and dual fans. The coolant will circulate at a consistent rate regardless of engine rpm and air will flow based on same principle. Might be a bit lean also. Good luck.
I have a 492 stroker in by 69 RR. For cooling, I use a 26" radiator, fixed blade fan and shroud. I also added a 16" electric pusher. This set up keeps temps in the 210 range when in traffic in Florida heat. At night, or on cooler days, temps stay around 190 without needing to turn on the electric fan.
Parts store water pump, aluminum housing, 26” radiator with shroud, 7 blade fan with clutch. Has cooled several big power stroker hemis and now this. Most electric fans seem to rated at free flow rather than through a radiator so very few perfom well. It’s also a huge tax on these 50 year old electrical systems.
Try all the 'obvious" upgrades to the cooling system first...

My trivia questions if further diagnostics have to go further being:

What are the Engines Internal Bearing Clearances on:
Main Bearings ?
Rod Bearings ?
High Volume Oil Pump and the Oil Pressure readings cold... hot... and does the Engine Temp heat "sink" or climb steadily over time during operation ?

Yours may be fine and NOT related ?
But just say'in....
some of the biggest issues we see with complaints of Stroker's "overheating" ?
is the guys who just screw the Stroker Kits together and not paying sufficient attention to the Bearing Clearances "as delivered" ?
Oil Clearances are related to Oil temperatures in operation... which are invariably related to higher cooling system loads/temperatures ?
.002" on the Mains and .0015" on the Rod bearings is a sure fire way to have overheat issues in a Stroker.... no wars wanted... believe whatever you want.
"go with the biggest aluminum radiator that will fit."
brass cools better than aluminum - just saying
and flat black anodized aluminum cools much better than polished
Core Dimensions: 19.75 x 27.88 (20 x 28 Chrysler Imperial 67>
New Yorker was 17 x 26 or 17.5 x 26
some replacements are only 17 x 25 core
Earlier C body could be 17 x 24
Dodge 440 B series van is even larger (talk about running hot)
I'm using a 73 New Yorker Radiator in my Dakota
and put a New Yorker Radiator in my 68 C body
much larger than stock 318 radiator
you can get tanks (largest that will clear) and fins and have one built
I've even replaced the narrow radiator core supports
Whatever you find BB. Report back with the cure!
I know that some do not like electric fans but this is what I know from using them . First thing is having to deal with the high amp pull of the hi out put fans . Spal recommends to use their relays . They have a heavy duty plug in at the fan with a ground and a hot lead . The relay has to heavy leads that are long enough to run to a trunk mounted battery . They recommend that the inline fuse be placed no father then 12 inches from the hot lead on the battery . The two heavy hot leads one red to hot side and yellow to ground post . There are 2 smaller wires coming out of the relay and they go to the power source when powered up they pull the relay in to start the fans . No high voltage pull thru the old wires, only thru the larger diameter ones . They can to turned on manually with a switch or a screw in fan thermostat and will come on at 185 degrees .
Back 25 years ago I built a 1941 Willys coupe had a small block with an aluminum radiator , had to use 2 electric fans but with no shroud due to clearance issues . They worked great and used a switch to cut them on . Drove the car across county from NC to AZ and back 3 week trip and 5000 plus miles . It has over 50,000 miles on it and has not given me any trouble . I forgot to cut the fans on one day in Tucson and the out side air temp was 115 , looked at temp gauge and it was 235 degrees , cut the fans on and the gauge was back to 185 in less that 5 miles . Just my 2 cents worth . Included a pic of the wiring on the Spal relay . Thanks John
One thing that you have to consider useing electric fans with a mechanical fan is it could create a "vortex" for lack of a better term. Then you have the air flow being disturbed in between the two and accomplishing nothing.

Not having a mechanical fan placed correctly from the radiator won't do much. Having a mechanical fan inside a shroud in the wrong location won't help.

I like what Ma Mopar designed. It works.
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