I have a 350CI 400 HP engine in my car. Its a tight fit and I have always has some cooling issues. I'm revamping the system to try and improve cooling.. The engine is lower than the rad so I have a filler block on top of the intake above the thermostat to make this the primary fill point and the high point in the system. It has a 16lb cap and overflows to a remote recover tank. The rad has a 24 -26 lb cap so it will not open before the 16lb cap. I replaced my old custom brass and copper rad with a new 3 row, .75 tube Champion aluminum rad. and improved the upper and lower rad hoses. I replaced a 160 degree stainless thermostat with 3/16 holes drilled around the perimeter with a virgin undisturbed 180 degree high flow thermostat ..not sure which was a better use for the system. Space is tight and there is no room for a mechanical or electrical puller fan in front of the engine. I have a 17" pusher fan mounted in front of the rad with about 1 1/2 inch air gap. Its shrouded but I plan to improve the current shroud and ducting on the front of the car. It has a 175 degree auto switch. I'm looking for suggestions on any mistakes o might have made or thing I might improve. Attached is a picture of the current set up. Thanks . .
Pusher is less efficient than puller, but if there's no room, you do what you can. Does the hot air have somewhere to go? Looks like the upper hose routes nicely, is the lower also good? Sent from my iPad using The H.A.M.B. mobile app
Does the shroud cover all of the rad? I wonder if the shroud and the fan itself are restricting some of the airflow.
Ya I would like to have been able to use a flexalite on the engine side too. I might have made a mistake with a 3 row .75 tube rad as compared to a 2 row 1" which might have let more air through the rad easier. The bottom hose is a straight shot so its pretty good. One significant option that could be made is to add a Stewart In line Electric booster pump. It increases flow by 300 % at idle speed but will not do anything to improve air flow over the rad. Its also will make the system a little less clean looking. I cannot move the rad far enough forward to gain enough space to change the pusher to a puller set up.
The fan covers almost the whole front of the rad and sits inside a deep round tunnel. I think it can be improved a bit by eliminating some possible minor possible leak areas and improving the ducting to the entry of the tunnel. Attached is a front view of the fan/shroud assembly. Its a little hard to see. The Rad currently has a piece of cardboard in front of the fins to protect them till final fitting is complete.
I can chime in. But not to much knowledge as that looks like it is wedged in there and nothing else can be done to much. But couple options. 1 try to go with a short water pump and put a mechanical fan of some sort. 2 Or electrical water pump and see if you can get a puller electric fan.
Increasing the flow won't necessarily cool it down. Thanks for the front end picture. My question was answered. Dedenbear make water pump that may work for you. Enabling a fan to be rear mounted
Can you move the radiator forward the thickness of that pusher fan and get a mechanical fan in there?
My 2c. Do you have an automatic tranny? Perhaps that is the source of some excess heat. Double flow radiator? 3/4 diameter tubes? Perhaps the coolant doesn't stay in the radiator long enough. Have you checked the "in" and "out" sides of the radiator for temp change? How hot does it get anyway? Is the fan too big? I have never seen a design where the fan was, as yours looks like, bigger than the radiator. Perhaps the fan is not moving enough air because the area behind the fan is restricted in comparison to the opening.
Buy yourself a laser heat temp gun, harbor freight has them on sale $40, check temp difference from in to out, I believe it should be 30/40 deg difference, also the water can flow too fast and will not cool properly and is problem at idle/traffic or building temp at speed ? HP makes heat, your cooling system becomes more critical, your fan should have a CFM rating, probably want 2500 minimum, fans come w/specific design blades for push or pull, some are not reverseable, it will run, but not efficiently, looks like your fill can needs to move up and be vertical, move it back from radiator to gain height IMO and always use a thermostat w/ a hole so when filling, so air in not trapped, switch to remote tranny cooler, use water wetter type additive, these are some suggestions from my experiences, not a pro wrench and what type of car are we looking at ? Good Luck w/ your problem, someone on here will offer the suggestion that works, sometimes it's something small in detail.
I second this suggestion. In my opinion a belt driven is much more effective than any electric fan. Jimmie
I agree,it looks like you have enough room to remove the electric pusher fan and move the radiator forward enough to use a good steel blade mechanical fan,the cheap flex fans are junk and won't work as well as the electric fans. HRP
Thanks .. I have a short hi vol pump n right now. . I would love to make space for a mechanical fan but not looking like its possible.
So it gets hot both at slow speed and on the highway? That's generally the determination if it's a fan problem or a flow problem.
So which is which? At speed I would think the fan is not a big factor so heating up at both would more indicate a flow issue.?? .
At low speed the fan does the job of forcing cooling air through the radiator, at high speed you shouldn't need a fan at all to get enough cooling air. Overheating at low speed implies a problem with the fan, overheating at high speed implies too small radiator - or other issues causing them not to function as intended.
Ok here i go again. As im reading your first post and looking at the photo. I see and read a couple thing more to add on that is over looked. 1 timing can make it run hot if it is not set right. Ive read a post in the past over heating issues or something a couple month back and it was the guys timing. 2 pusher fan if that all that fit shouldnt be to much a problem but as posted in previous it is not as eficiant but will do and on highway shouldnt get hot but if that temp is geting up fast check your timing look into detail on that. 3 relocate if you have auto tranny the cooling lines to a seperate cooler and not into the rad. Good luck and hope this helps. Check that timming.
So just how much space is between the end of the water pump shaft and the Rad? If that's 2" you can get a fan blade in there. It looks to me like your Belt and pulley is what stops you from mounting a Fan blade. Also high volume pumps are not always a good idea. Slow the water down and let it stay in the Rad a little longer. With that I'll add, close up the windows along side the Rad so all frontal air must pass through the Rad and not go around it. Silly as it may sound, check your Fan rotation. The Wizzard
One more thing. Make sure your pump is correct for the drive system your using. A pump designed for serpentene belt drive is reverse rotation. BIG problem with a V belt drive. The Wizzard
Just a couple of thoughts...I wouldn't oversize the fan like that, find one that has a diameter equal to the width of the radiator. The second thought is, what exactly is holding up moving the radiator forward? It's fairly easy work to modify the radiator tanks if they need a bevel or notching to get you forward a bit. Obviously, timing and fuel mixture play a role in engine temperatures too.
Another question is which is the best thermostat to use. Previous to putting this new rad in I have used a 140, 160 high flow , none, and lastly a 180 with 6 1/8 holes drilled around the circumference. Currently I have a 180 high volume installed. I remember having cooling problems when running at higher freeway speeds but not so much at city speeds. Can't remember about idle. The car is a 1979 MGB. The engine is mated to a 350 automatic and has a 3:90 rear end. Note I have not run the engine yet since doing some engine mods and working to improve the overall cooling system components and set up before going live. . No way a mechanical fan will ever work even if I could move the rad forward because the engine sits too high relative to the rad and it would not cover the rad properly and there would also not be enough. hood clearance for the blades. Hood clearance is also a problem with the top of the rad. In order to put in an electrical puller I would have to move the rad forward and down. As it moves forward it has to go down. Clearance below the front valance and ground might become an issue but will give it a serious consideration. .
Attached are a couple photos. One from the front of the car. Note the bottom of the rad is currently at the bottom of the front lower valance. The other shows a top view. You can see there is only about an inch to the pulleys, belt and alternator etc. You can also see the pusher fan shroud is about 4 1/2 inches wide. it MIGHT ..be possible to remove the pusher and its shroud and move the rad forward slanting the bottom out enough to make enough space for a thinner puller assembly. I wonder how much that change might make? I would probably not do that though unless the current set up does not work.. BTW.. I worked with a fan research company who designed , tested and built this fan assembly for Ford. At the time it was the largest and most efficient OEM fan available, although not used as a pusher, but why I originally selected it.. (and it was free) .
Not thinking the fan is oversized . its almost the same diameter as the width of the rad core. The slant of the hood vs moving too far down below he front valance and resulting road clearance are my main concerns. Slanting the rad might be a possibility but not sure how that effects air flow at speed.
Hopefully this rad will be more efficient than the old one ..it is supposed to cool up to 450 hp and solve the overheating at speed issue.
Less than an inch ..but as stated its way too high relative to the rad face and the hood clearance for a mechanical fan. Looking to close up the windows as you suggested.
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