I recently read an article concerning cooling fans, and their abilities to move air under various situations [ pulley sizes, engine speeds, etc] . When using the factory size pulleys and a stock fan and cooling tins, after aproximatly 4000 rpm, the fans ability to push more air begins to diminish because only so much air can be pulled in and only so much can be forced out. This is why at this point, the drive belt is already beginning to slip and as rpm's increase, aditional horsepower is required to drive the slipping belt because the fan is fighting the belt . VW was obviously aware of this and so through design it was incorperated. It was also stated that by replacing the factory size pulley with a "power pulley", the effective amount of cooling air available was reduced by only about 11%, which I would personally consider acceptable under most circumstances. Now my curiosity has me wandering how many people out there are running serpentine belt systems with the hopes of eliminating belt slippage, and as a result, destroying cooling fans. I am also curious as to how much available horsepower is being lost due to the fact the fan eventually comes up against a [stone wall], resistance.I suppose that question will only be answered by a dyno. Comments or theories???????

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Don't sweat the petty stuff, pet the sweaty stuff.

Get a Top Cog Dayco belt , a good steel pulley,don't do any unnecessary wubows in the parking lot, let the motor idle a minute or 2 b4 shutting down, rtv all leaking tin gaps,rtv gap between fan and shroud then cut loose with a razor blade around fan, timing rite with good octane,no lean mixtures.The fan was just made for a 1600 motor. Can I take the radiator off my honda and put it on my 350 chevy?And don't run around in 1st or 2nd gear wide open.Let it chug a little but not enough to beat bearrings.The belt should have a 1/2 inch thumb deflection beween the 2 pulleys.

i was reading somewhere a serpintine belt system isnt nade to run on a woods car,ive seen one ran on a woods car and the idler pulley was eat up,i guess from the dirt,,dayco top notch or cog is the best belt made,they will last forever

My thoughts on the serpentine belt arrangement is that it may be fine for under 5000rpm, and an occasional blast over that, which may be fine for the "daily driver", but on a weekend thrasher, climber, the above normal rpm's over a dd would certainly lead to fan destruction due to restriction and resistance, eventually. This is just one of the many reasons draggers don't run one at all. WE have no choise. And don't say w/c, because that it not what this is about. What is being run on a/c woods buggies, what works, and what doesn't??? I guess what we all need to know is WHAT DOESN'T. Thanx for the input.

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Don't sweat the petty stuff, pet the sweaty stuff.

just an idea. Don't shoot me. What if dual carbs was on nothing but a long block.No shroud alternator nothing ,just nekid with a fuel pump and distributor. And ya laid a bigo electric fan off a big V8, mounted flat.Keep your pulley and run your alternator mounted to the side.omg!Lay your oil cooler flat between the two, above your block.

thats the way the big drag motors are,jus a couple of electric fans and thats it

You can buy a "killer B" race fan to replace the stock fan, they are designed to pull/push more air at lower rpm's all the way to the upper rpm's. The engine will sit and idle and it will pull a nice load of air like you can almost see the leaves blow away from underneath the buggy, the grass waving around and even the dust getting stirred up.

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"Loud pipes saves lives"

I runa killer Bee fan its welded. When I put it on i could tell a big difference in the amout of air pushed across my cylinders. A freind of mine run a serpentine set up and has had no problems. He runs his pretty hard but also keeps his ride very clean. Anything not keep clean or maintain is certainly gunna fail early.

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Turbocharged Ecotec,vanogon midshift,Berrien WoodsBuggy wagon.

Yes . I've seen that tears ago but a modern radiator fan I have not.

Ok im not going to start a new thread over this but im curious to hear your guys opinion's on what type of fan shroud you think provides the best cooling or air flow.Im running a center mount shroud which claims to force more air onto the cylinders.Lets hear your opinion's and why.

I like my doghouse shroud and I heard that the type 4 center shroud cools better and more evenly than the doghouse style ones does but I never had any issues yet.

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"Loud pipes saves lives"

I run a serp. belt system and it does fine in the woods. I rarely turn my motor over 5500rpm. Not much point when I built the thing NOT to turn high RPM's. 4 grand and it's putting down great power and it stays cool. I like the serp. system and the main reason I went with it was to bring the van speed back UP with my dry sump system. The type of riding I do is not 7,000 everywhere I go. I lug around the woods at slow speeds.

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Buy the best and cry once.

Roy is old, keep this in mind guys.

I run a welded fan, serpintine pulley and a Jack Raby's DTM (down the middle) fan shroud. I Think it's an awesome setup. I have put a laser temperature gun on all cylinders and they were all within 5 degrees from eachother. The only prob is that a DTM is over $350. Is it worth it? Well..... To me it is. With the DTM my motor oil temperature never went over 180 degrees, and that was a 2387 turbo charged fuel injected with me beating the daylights out of it.

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When in doubt, hit it in second gear!