1969Fstback 58 Report post Posted May 30, 2017 Over the winter I put a new 3 core aluminum radiator and went from a 195 to 180 thermostat. I started it in garage and it held at 180. I did buy a shroud, but it appears I have oversized flex fan and it didn't fit. So I took it for a drive and it held 180 entire time til I was coming back my driveway. It crept up to 190 when I was pulling it in the grarage. Would the shroud make that much difference? Or what else to look at? Once it coold I checked the radiator and it was well above the cores. I has the original 302 2V. Not sure on specs, but sounds like it has a little cam and has holley 570. What size diameter is factory fan? Guessing at slow speeds the shroud becomes more crutial. Quote Share this post Link to post Share on other sites
barnett468 418 Report post Posted May 30, 2017 put the shroud back on it. Quote Share this post Link to post Share on other sites
BuckeyeDemon 211 Report post Posted May 30, 2017 i thought 180 was defined as the temp at which a thermostat just starts to open and it takes around 15-20 degrees more for it to fully open. so i would think you should only be concerned if i creeps beyond 200. Quote Share this post Link to post Share on other sites
barnett468 418 Report post Posted May 30, 2017 10 degrees is the most the temp will ever rise above the t stat rating on a very good system and the rise can be as little as around 5 degrees. the fan draws a lot more air thru the rad when it has a shroud around it so it is always safer to use a shroud especially if it is already getting 10 degrees hotter at low speed than the t stat rating and the weather may get hotter than it was when this occurred . for example, the temp may be passable now in 70 degree weather but if may run much hotter in 90 degree weather or with the ac on etc. as far as the safe max temp an engine can get to before some type of damage may occur, it is at least 220 degrees . my 1996 corvette had an extra cooling fan as a factory option and it was set by the factory to turn on at a whopping 240 degrees and this was on an aluminum head engine. nascars run over 220 degrees the entire race. . Quote Share this post Link to post Share on other sites
1969Fstback 58 Report post Posted May 30, 2017 The car didn't have a shroud when I got it. When I got the radiator I picked up a factory shroud, but seems my fan is larger then what a factory shroud calls for. I was going to measure my fan this evening and probably pick up a new flex fan the right size. What diameter was the factory fans? Quote Share this post Link to post Share on other sites
1969_Mach1 333 Report post Posted May 30, 2017 6 hours ago, BuckeyeDemon said: i thought 180 was defined as the temp at which a thermostat just starts to open and it takes around 15-20 degrees more for it to fully open. so i would think you should only be concerned if i creeps beyond 200. You are correct. I've put several thermostats in a pot of water on the stove with a thermometer in it (only contacting the water). They start opening at the rated temperature and depending on brand are fully open usually 10 to 15 deg above the rated temperature. For some reason, the high quality Stant Superstats I have tested are always close to 15 deg above the rated temp before being fully open. I've had best luck with Stewart brand high flow thermostats with the 3 bleed holes that look like the old Robert Shaw brass thermostats that were the norm back in the 1980's. On our daily drivers, I always go to the dealer and get OEM thermostats. Quote Share this post Link to post Share on other sites
1969Fstback 58 Report post Posted May 30, 2017 So, in theory, while cruising at 50 it may never fully open if there is enough air and circulation with it partially open. Likewise, sitting in my driveway after running it, I'd expect it to probably reach 195 fully open then likely the temp start coming back down due to maximum circulation. I'll prob put the shroud on anyway, but that may be something it takes me 3 or 4 weeks to get to. In meantime I will keep an eye on the temp gauge to see how it behaves. Quote Share this post Link to post Share on other sites
barnett468 418 Report post Posted May 30, 2017 it may very well go over 220 in your driveway on a hot day . i don't have enough info to know that but obviously its ok to drive as long as you monitor the gauge and stop if it gets to the 210 - 220 range because it may run away after that and overheat quickly . every engine build and cooling system is different. Quote Share this post Link to post Share on other sites
1969Fstback 58 Report post Posted May 30, 2017 5 minutes ago, barnett468 said: it may very well go over 220 in your driveway on a hot day . i don't have enough info to know that but obviously its ok to drive as long as you monitor the gauge and stop if it gets to the 210 - 220 range because it may run away after that and overheat quickly . every engine build and cooling system is different. Growing up I heard different conflicting recommendations to a temp running away. I was told by some if it gets real hot not to shut it off, park it and let it idle to keep it circulating and let it cool. Also been told to shut it off. Which one is best? Quote Share this post Link to post Share on other sites
fvike 173 Report post Posted May 30, 2017 2 hours ago, 1969Fstback said: The car didn't have a shroud when I got it. When I got the radiator I picked up a factory shroud, but seems my fan is larger then what a factory shroud calls for. I was going to measure my fan this evening and probably pick up a new flex fan the right size. What diameter was the factory fans? Unless you want the factory look, you might want to reconsider using a factory fan. Engine Masters tested it, stole 30 hp. https://www.youtube.com/watch?v=ZXdLgaFXZzs&index=2&list=PLGvTvFzdMg_O2T3UdUEt5dIHutSOu7srE Try to find a good electrical fan that will fit in the shroud, (or has it's own shroud) and get a quality fan controller like the ones from Autocoolguy. Those controllers have soft start and is solid state transistors so you wont have the arcing of a relay operated fan that only run at full speed. Quote Share this post Link to post Share on other sites
1969Fstback 58 Report post Posted May 30, 2017 Nothing on this car looks like factory for most part. So I have no attachments to factory look. It has a aftermarket flex fan that is too big to fit the factory shroud. I was thinking either going with a smaller flex fan to fix the factory shroud or get a more universal larger shroud. Yeah at some point I was thinking of switching it over to electric. The FItech fuel injections has a built in fan controller. I have plans to make that switch later this year. If I do I was gonna gonna switch to electric fan then. 1 magician reacted to this Quote Share this post Link to post Share on other sites
jholmes217 65 Report post Posted May 30, 2017 If your fan is hitting the shroud at one location, you could trim the shroud where it hits. The flex fan probably doesn't help either. My car overheated in a parade last year, and I was using a new aluminum radiator, factory reproduction shroud, and a flex fan. Thermostat was a new Robert Shaw 195 degree. I put a reproduction clutch fan on it, and ran it in my garage for about 20 minutes after it warmed up as a test, and it stayed in the 200 degree area. That was idling with the front end of the car in the enclosed end of the garage getting no wind, so I'd say the new fan fixed my problem. It did hit the shroud at the bottom, so I trimmed the shroud until it didn't rub anymore. Does it rob power? Probably. But a overheated car with the hood up and steam rolling out makes zero power. 1 Dave R. reacted to this Quote Share this post Link to post Share on other sites
Mach1 Driver 560 Report post Posted June 1, 2017 Google "uploads from West Coast Classic Cougar- You Tube" and watch #4, which is titled something like "Radiator and fan upgrade for SBF". You can use a BBF 7 blade fan with a clutch and it only robs around 12HP (don't buy theirs unless you have a lot of cash). Check the bolt pattern on yours, and go to Ebay. He explains why flex fans are a problem. Quote Share this post Link to post Share on other sites
1969_Mach1 333 Report post Posted June 1, 2017 I changed from a 17" 6-blade flex fan to a 7-blade 17" OEM clutch fan on my car. I found the fan on EBay and purchased a new clutch from NAPA. The fan I purchased on EBay was originally used on Cougars and Shelbys with small blocks and A/C. The 7 blade clutch fan is cools much better than the flex fan ever did and is much more quite.. 1 magician reacted to this Quote Share this post Link to post Share on other sites
mustangmike6996 34 Report post Posted June 1, 2017 I installed an electric cooling fan on my 2 core radiator. It pulls a ton of CFM. I have not taken the car on a very long trip yet but it seems to keep the car cool at idle in the driveway. I installed a different Tstat housing with a NPT bung where I installed the temp switch. 1 RPM reacted to this Quote Share this post Link to post Share on other sites
1969Fstback 58 Report post Posted June 1, 2017 4 minutes ago, mustangmike6996 said: I installed an electric cooling fan on my 2 core radiator. It pulls a ton of CFM. I have not taken the car on a very long trip yet but it seems to keep the car cool at idle in the driveway. I installed a different Tstat housing with a NPT bung where I installed the temp switch. The housing idea is great. I was looking at controllers last night that had the temp sensor that goes in radiator fins. I wasnt a big fan of that. Pun not intended. Quote Share this post Link to post Share on other sites
RPM 1,190 Report post Posted June 1, 2017 51 minutes ago, mustangmike6996 said: I installed an electric cooling fan on my 2 core radiator. It pulls a ton of CFM. I have not taken the car on a very long trip yet but it seems to keep the car cool at idle in the driveway. I installed a different Tstat housing with a NPT bung where I installed the temp switch. I did the exact same thing with the same results. It also stays right at 185° on trips. Haven't driven it on 100° + days though. Quote Share this post Link to post Share on other sites
barnett468 418 Report post Posted June 1, 2017 the sensor should go before the t stat Quote Share this post Link to post Share on other sites
1969Fstback 58 Report post Posted June 1, 2017 Putting it before thermostat makes sense. Could you put a T on the heater hose? How much does the cooling fan drawl against the alternator? Quote Share this post Link to post Share on other sites
barnett468 418 Report post Posted June 1, 2017 1 hour ago, 1969Fstback said: Putting it before thermostat makes sense. Could you put a T on the heater hose? How much does the cooling fan drawl against the alternator? well that would be in the lower hose which will give you the wrong reading plus you can not use a t because the reading will be inaccurate. Quote Share this post Link to post Share on other sites
MN69Grande 203 Report post Posted June 1, 2017 3 hours ago, 1969Fstback said: The housing idea is great. I was looking at controllers last night that had the temp sensor that goes in radiator fins. I wasnt a big fan of that. Pun not intended. I've got a DCC Controller with the probe in the radiator running the Contour dual fan setup. It really moves air and after a little adjustment the probe is doing the job just fine. The probe is under the fan shroud so you don't see it anyway. The thing I like most about the controller is that it is a soft start. They also have a jumper for an A/C override or manual switch. Quote Share this post Link to post Share on other sites
barnett468 418 Report post Posted June 1, 2017 the dcc controller is probably the best one made. Quote Share this post Link to post Share on other sites
rangerdoc 22 Report post Posted June 1, 2017 Any chance some of you could post some links to these parts? -DCC Controller -tstat housing with bung -7 blade OEM clutch fan And will any of that work with a 24" stock radiator? Any alternator upgrade needed? Quote Share this post Link to post Share on other sites
1969Fstback 58 Report post Posted June 1, 2017 31 minutes ago, rangerdoc said: Any chance some of you could post some links to these parts? -DCC Controller -tstat housing with bung -7 blade OEM clutch fan And will any of that work with a 24" stock radiator? Any alternator upgrade needed? I suspect I'd need to upgrade my alternator to run a fan. Quote Share this post Link to post Share on other sites
MN69Grande 203 Report post Posted June 1, 2017 1 hour ago, 1969Fstback said: I suspect I'd need to upgrade my alternator to run a fan. DCC Controller - http://www.dccontrol.com/constant_temperature_controllers.htm - But note if you order it today it won't show up until August and the owner will pretty much ignore any emails requesting status. You just have to trust it's coming and will be worth it. Flex-a-lite has controllers galore on Summit Racing if you can't wait You will want to upgrade your alternator if you go with an electric fan. Either get a 100amp 1 wire (http://www.cjponyparts.com/powermaster-alternator-100-amp-one-wire-v-belt-pulley-smooth-look-1965-1973/p/ALT38-V/) or do the 3rd Gen conversion (I used this kit and a late 90's Windstar 130a alternator from a junk yard http://www.mustangsunlimited.com/Mustang/Ignition-Electrical/Alternators-Related/Alternator-Hardware/PA-Performance-Alternator-Conversion-Plug-3G-Upgrade-1965-1985-Mustang.axd, you will also need to update the charging wire to 6 or 4 gauage with a fuse or fusible link, Finally you will need to disconnect the ampmeter or it will burn out - or convert it to a volt-meter http://www.rccinnovations.com/index.php?show=menu-volt-all) I have a 24inch radiator and a Ford Contour Dual Fan easily fits it. Some people go with the big Taurus Fan, both are easy to get. I paid more for the controller than the fan. My guess is this is the style T-Stat housing being described earlier. But as Barnette468 said the port is on the wrong side of the t-Stat.http://www.mustangsunlimited.com/Mustang/Heating-Cooling/Thermostats-Related/Thermostat-Housings/Thermostat-Housing-w-Port-1965-1973-260-289-302-351W-Mustang.axd Quote Share this post Link to post Share on other sites
