As summer approaches, I suspect I will have a cooling problem in my coupe while sitting in a traffic jam in 90 degree weather. This may be exasperated for my trip to GG Indy in June. Here is the equipment I am running: Aluminum rad 15 inch high pitch fan No overflow tank No a/c or anything else a real hot rod should have Timing set correctly Currently runs at 185 degrees on highway Sitting in moderate traffic, moderate temp, the gauge climbs to 200+ I'd like to avoid adding an electric fan and have been thinking of installing a shroud. So, my question, are there universal after-market shrouds? Are they any good? Easy to install? What are you running for a shroud? Any other suggestions? Thx
What kind of power plant you running? What kind of aluminum radiator? Does your fan have a clutch? I've seen "universal" fan shrouds for sale but to honest they aren't universal. They don't like to fit tall narrow radiators.
[ QUOTE ] are there universal after-market shrouds? Are they any good? [/ QUOTE ] Yes. Walker Radiator carries them. They fit a specific radiator and you cut the center hole to match the fan placement and diameter. A Sabre saw is required for the cut. Make a point to lay 2" or so masking tape over the area you're going to cut so the shoe of the Sabre saw doesn't mark up the pebbled plastic. [ QUOTE ] Timing set correctly [/ QUOTE ] That includes a vacuum advance sourced to manifold vacuum does it not? ****uming you're running a GM engine. (SBC?) If you're not running vac adv sourced to manifold vacuum that's probably the source of your in-traffic overheating problem.
try this, they work well.... http://www.yogisinc.com/Detail.cfm/-/Product_CD=WS-40/Category=425/product.htm
you stated you didn't want to use an electic fan , i didn't like them either about 20 years ago....but they do work!..i've put one on everything i've built since. the key is to use a good high performance fan that puts out some cfm's.....don't use some cheap POS from autozone for $50...you need 2500-3000 cfms and that will cost around $150 put a Spal 2700 CFM pusher fan in front of your radiator on your 36 and you will not have to worry about it.. put in a relay since they draw a lot of juice.. a puller fan behind the radiator would be more efficient,but you probabilly don't have room last year at GG des moines i was criusing around the grounds all day friday ( hot as hell) in a `32 ford..walker Z line radiator , Spal puller fan...never got over 170 degrees
Power plant is a BBC (454) out of a '90 SS pickup. Yes, it has the correct vaccum advance to the manifold. The radiator is a PRC (Performance Rod & Custom- Ohio). There is no clutch fan....just a regular 15" high pitch fan. This past winter I moved the fan closer to the rad via an aluminum spacer. Distance to rad is now 1-2". Thanks for the suggestions re: where to find a shroud. Any other advice is more than welcome.
I'd try to keep the fan closer to the 1" than 2 inches from the radiator. Either way, just a piece of sheet metal bent around the fan will do the job. I used aluminum, since I have an aluminum rad too. You want to have the shroud about 1/2"-3/4" from the ends of the blades. It should overlap the blades by about 1/3 of the blades' pitch. You can also dilute your coolant to about 20% antifreeze/80% water. Water cools better than antifreeze, and you can really go down to 15% of the green stuff and still have effective protection against freezing. Since you live in a colder climate than some of us, you'd brobably want to go closer to a 50-50 mix for the winter months.
I'd like to see what you come up with and how you install it for my own car ('36, 302, original recored rad, flex fan)
<font color="green">I****ume you are talking about a high pitch flex-fan? I was running one on the 41 and was having some trouble. I found some that are shaped different, two of the blades are offset. This is supposed to keep the blades from forming an actual barrier when they flatten out. Anyway, It was the only thing I changed and it really made a difference. Can you not run a larger fan? What thermostat are you running? RASHY </font>
A shroud sounds like a good idea. I have seen a number of them in junkyards that could be adapted many radiators. The mid '70's GM truck shrouds are big enough to be cut down six ways to sunday to make a decent shroud. Harbor Freight carries a plastic welder that might help you to create a rockin' plastic jobber if you don't want to use sheetmetal. It will also help to cool your oil and******* fluid (if it's an automatic*******). Even the small coolers can help a lot in hot weather. But really if you can get a rat motor to run at about 200 in the summer, you're doin' OK. At least in Texas. LOL Big Daddy Eric
Shrouds can be very effective. My '41 evaded all attempts to make it cool until we installed a shroud; has never overheated since. Used the Walker plastic shroud with cut-to-fit hole.
Another thought; are you running all the origional sheetmetal on the front end? I am referring to the little pieces that keeps the air coming into the front grill from going around the rad.and leaking into the engine compartment. What this causes is 1) less air actually going thru the rad (with the resultant loss of cooling) and 2) makes a higher pressure area behind the rad. (in the engine compartment) and making it harder for the air coming thru the rad. to enter the engine compartment. Also might want to investigate your inner fender panels; may need to punch some more louvers in them to help the engine compartment air escape.
Rash.....its not a flex fan. This one is a sturdy SOB but does have the offset blades like you mentioned. I had a flex fan on last year but have heard horror stories about blades flying off and deep-sixing the radiator. A few guys have told me 200+ is nothing to worry about but I have this mental problem about going over 180.
[ QUOTE ] Another thought; are you running all the origional sheetmetal on the front end? I am referring to the little pieces that keeps the air coming into the front grill from going around the rad.and leaking into the engine compartment. What this causes is 1) less air actually going thru the rad (with the resultant loss of cooling) and 2) makes a higher pressure area behind the rad. (in the engine compartment) and making it harder for the air coming thru the rad. to enter the engine compartment. Also might want to investigate your inner fender panels; may need to punch some more louvers in them to help the engine compartment air escape. [/ QUOTE ] You're right!! I didn't install the piece that mounts at the bottom of the grill that pushes air up into the rad!!*****, why didn't I think of that?? I'll install it this weekend. Do you think that will help when idling though? I have a ton of louvers in the inner fender panels.
"Do you think it will help when idling though?" It should help providing you have proper spacing between the fan and rad. i.e. the fan shouldn't be too far away. And the variable-pitch fan blades (flex-fan) will also help. I would also think about getting a o'flow tank; if the rad. heats up and pukes some fluid that isn't captured and put back into the system when it cools down, that's just like running a rad. 3/4 full. And finally, besides the under-grill tin, check for any pieces that go between the inner fenders and rad. as well as between the hood and the top tank. In other words, make it so that any air entering the engine compartment has to go thru the rad. If it gets hot at speed, think about making a (unseen) chin spoiler directly under the lower tank (can be really small and unobtrusive) to make a low pressure zone behind the radiator. Just some thoughts for a big engine in a small hole... Best of luck.
Big Olds has a 455 in him and was running very hot while cruzn with the original rad in him. I had an AL one built at a local shop that specializes in rads for race cars. I also had them make an AL fan shroud as well. The cost of the whole setup was much cheaper then the cost for just an aftermarket rad. It does run around 200 while cruzn but I'm told that is VERY NORMAL for a 455. If a shroud from them is something your interested in I can pass along the number. I can even pick it up for you and bring it to Indy if you'd like. Also, when Big Olds heated up while cruzing I was getting alot of hesitation, kind of like the start of vapor lock. I went to the local speed shop and bought a black 2 inch riser for under the carb. Forgot whats its "formally" called. Installed it in about 5 minutes and have yet to have the fuel heat up ever again. I think it was about a $20-$25.00 dollar item. I'll show it to you at Indy.
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