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#1
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360 Cam bearings and other block mods?
Ok, I'm about ready to put the 360 back together, but I have been tring to find if anyone sells grooved cam bearings to allow full time oiling to the rocker gear? If not, what bearings should I use? I am thinking of using the Clevite CLE-SH875S bearings if I can not find grooved ones.
I have seen some cams that are grooved, but the one I have is not, it just has the cross drilled holes, and the bearing width is narrower than the older cam I took out of the engine (if that matters.) Anyhow, would grooving the cam or bearings create too much of an oil pressure drop? I would like better rocker oiling with the aluminum roller rockers I have. Also, any other oiling mods? What about re-drilling the main oil feed holes from 1/4" to 5/16"? I also plan to use a 1/2" NPT tap to tap and plug the front top water holes (one on each side) in the block deck to force the water to circulate more before exiting into the heads. I got this idea from the book "How to Build Big Inch Mopar Small Blocks" by Jim Szilagyi. Any other ideas? I already cleaned up the 1/2" oil supply holes from the pump to the filter. The 1/2" drill bit actually removed some steel, so I'm not sure what the original size was? I haven't removed the plug that forces the oil through the filter to check the size of the oil feed to the lifter galley, but I will probbly check it too since I have all the other plugs out of the block. |
#2
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I don't know about the cam bearing issue. I'll have to keep on this thread.
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#3
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What RPM do you plan on spinning the 360 to?
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#4
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You don't need groved cam bearings or cam either. Mopars get too much oil to the rockers already. That's not and issue. It's getting oil to both ends of the mains that matter. Run stock cam bearings, and fully groved main bearings and stock rod bearings. You can increase the oil passages one size larger if you like. Main thing to do is connect the right rear lifter galley with the LF so you oil it from both ends. You can also read about this in the circle track section under Sanborns oiling mods.
Don't block the water flow either. IT flows more than enough in the block, you need it to flow through the heads. You can get a kit to do this or make your own up. Tap the back end of your intake for 1/2 lines and run two to a modded Moroso type filler neck where you attach the top rad hose to. This will get the flow through the heads you need. Also the stock water pump cavitates at 4000 rpm so if your planning on turning some rpm with this thing you'll have to get some underdrive pulley's so it wont over heat. |
#5
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I never thought about the water pump cavitating. Good info DWC . I think i,m changing to a good electric on my b/rb
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#6
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Any of these mods will be overkill on this specific 360, it's just a RV engine, probbly want see much over 5,000 RPM, but after seeing the condition of the #4 main bearing, which was the only one that looks bad?, I was looking for any tips on improving the stock setup. I am using Clevite 77 full groove main bearings (same part number that was in the engine before.)
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#7
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Thanks. I ran an electric in the Duster with a big block and it will use one again as soon as I get it rebuilt.
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#8
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#9
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Pump Cavitation
Pump cavitating, is that at 4000rpm engine speed or water pump speed. Is there different pulleys available to slow the pump down? By how much can you safely slow the pump down and not have problems when driving in traffic or low speed? Electric sounds great but for my build up may be way over the top.
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#10
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That should be pump speed. And yes, there are pulleys that change the pump speed. Even stock ones.They all vary to some point. On my race cars we use a stock larger water pump pulley and a smaller crank pulley to slow it down. March sells them too, but a little pricey and they have a couple of different ratios too. An electric pump is not really over kill at all. It's actually much better than a stock pump cause flow stays pretty much constant. Use the electric pump and elec. fan and you'll gain some hp too since you take the drag off the engine.
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#11
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I have a set of the March pulleys. Serpintine set. I had no problems with cooling in My 4spd. Ebody Cuda. It has a 4.10 ratio and 27 inch tires.
The engine was a MoPar Create, 10-1 with the purple 292/.509 cam, Edel. intake & heads and Hooker super comps. |
#12
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Nothing is free. The drag you remove from the engine by removing the fan and water pump is made up for by the extra drag created by the alternator, to generate the electricity to turn the electric motors. There can be a couple execptions to this. With a thermostatically controlled fan, if your engine is running cool enough for the fan to shut off, you are saving the power that would otherwise drive a mechanical fan. Also, as DW mentions, the electric pump (most of them anyway, except for the Davies) run at constant speed, so at higher RPM you are not increasing pump speed and thus increasing HP usage. Of course if you are running in an event short enough where you don't need an alternator, this doesn't apply. Finally there is the old drag racer trick of putting a switch into the field circuit of your alternator so you can turn off the alternator during your run, reducing the drag. Just remember to turn it back on when you're done racing!
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#13
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The Alt. is spining and making power at the rate it spins at. A max output of the Alt. is possible at a low RPM. Install a dead battery in the running car @ idle and hook it up. Watch the needle jump. The rpm may take a dip, but is that because the Alt. doesn't have enuff output? It's feeding everything. Theres just more draw. If you had more electric devices, you could give it a brown out, so to speak. I gotta see a dyno tell me different. I just can't believe it other wise. |
#14
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The #4 main was the only one worn doen to the copper. Not sure if it got most of the trash from the wiped out cam, or if something plugged the oiling to that one bearing, that is why I ran a drill bit through all the oil feeds to the main bearings. As for the water pump, I am using the high-volume Mopar Performance one. Probbably not really efficent at high RPM, but with my setup I won't be over 3,000 RPM most of the time except when accelerating through the gears.
As for electric pumps and fans, they are more efficent, but cost more and you need to upgrade the charging system to really take advantage of them. One possable concern is also how long they last? I have used electric fuel pumps and cooling fans with out any reliability issues, but I don't know about the water pumps? The extra current load on the alternator will only take a small amount of power from the engine. In theory, 1 HP = 746 Watts of power. Since Watts is Current * Voltage, and assuming battery voltage of 13.2 volts, your electric accessories would have to draw 56.5 Amps to increase the load on the alternator by 1 HP. |
#15
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That's theory. The only way that you use less HP with an electric pump, is if you pump less water. That's entirely possible, in fact I seriously doubt that an electric pump can match the output of a belt-driven one at higher RPM. But, the thermodynamics is sound - energy cannot be created or destroyed. It can take a LOT of power to spin an alternator putting out full power. It would be interesting to see a dyno test of what the drag of an alternator is at say, 5000 RPM. Notice the magazine tests? They use electric pumps, but use the battery in the dyno room, no alternator. I really do wonder what the actual numbers would be in a real-world situation.
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#16
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#17
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Not so. You use less hp with electric water pump.Takes more hp to move water than an electric field. Water weighs what, 7 lbs. a gallon. And the elec. water pump pumps more water than a stock pump at higher rpms. Reason being that the stock pumps cavitate at 4000 rpm and gets worse as the rpms go up so you get less flow and overheating. Most people want to throw a big rad at an overheating car and most of the time it's timming,fuel, or pulley issues cause the pumps running too fast. |
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You can't get something for nothing, if you could, there would be such a thing as a perpetual motion machine. From what you are saying, DW, you could use an electric water pump to spin a water turbine, that could drive your alternator, and produce the electricity to run the water pump, and still have some electric power left over.
Impossible! It takes as much power to turn the alternator, as the power needed to spin the pump. More really, because no process is 100% efficient. The conversion of the motion of the alternator to electricity, and then back to the motion of the water pump is not 100% efficent, plus there are losses due to friction in the bearings, electrical resistance in the wires, and other inefficiencies. As such, you are NOT getting free power. The only way the electric pump will use less engine power than a mechanical one (other than not driving it off of the alternator) is if it isn't spun as hard. I will believe this, as the electric pump doesn't continue to speed up at higher RPM the way a mechanical pump will. |
#19
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Your hand would be able to charge the system. But not cool the engine. The water pump (Mech) takes a good amount of force (By hand) to move the water around, never mind the rate it needs to stay cool. The frictional loss is extreme in minimal from the Alt. However, if your Alt. is hard to spin, theres something wrong. He heh e. The water pump (Electric) also has a minimal loss in friction. But the motor of the pump does take some power to move at speed. (Probably listed on paper somewhere in the instructions or sales ads. The electric pump doesn't require that much electrical power to move by compare to the mech unit. |
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Tell you what Rob, then why don't you use this principle to build a perpetual motion machine? You could make billions! I'll tell you why you won't, and can't. Because it's simple physics. When you spin the alternator by hand, you aren't generating enough electricty to spin the water pump an equivalent amount. Do you know how regenerative braking systems work on electric cars? The motors at the wheels are switched to work as generators, and used to recharge the batteries. They can haul down a moving car pretty fast, one way of proving that generating electricity takes a lot of power. Another is a simple experiment performed in grammar school science class. Wire up a generator with a hand crank in a circuit with a light bulb and a switch. With the switch open, spin the crank. Then close the switch. The light comes on, and the drag on the generator is definitely felt.
It is the Second Law of Thermodynamics, energy cannot be created or destroyed. You don't have to believe it, but it is true nonetheless. As I have already stated, it may free up some horsepower in an automobile by using an electric pump, but it isn't because by some magic you have managed to create something out of nothing. It is because the electric pump isn't absorbing as much power as the mechanical pump, because it runs at a fixed speed, rather than increasing directly with engine RPM. |
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I think this is the biggest factor, the mechanical pump has to change speed with the engine, the electric pump maintains a constant speed. If you looked at the current draw when the electric pump is first turned on you would see it pulls alot more current for a second as it comes upto speed, after that the current drops off to just maintain a constant speed. Quote:
On an electric car it helps slow down the car, but if you tried applied the same idea to a cars alternator, you mat get the belt to slip, but it won't do much to slow the car down. Running some numbers, an electric car with a 50HP electric motor would take 37,300 Watts of power. If that motor was reversed into a generator, and the output current was shunted to 14 volts (electric cars run several hundred volts, this is just for what if's) the current output would be 2,487 Amps. If the electric car was running at 280 volts, than the current would only be 133 Amps. |
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#23
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Energy is lost, it just turns to heat
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#24
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You cant beat the simplicity of a belt driven pump, and the electric pump is expensive, and when you need parts for it, on the road, you are SOL, call the tow truck.
Drag only I can see the advantage, as you are within distance of your tow truck and tools, but I wouldnt want one for everyday use, and do they even recommend using them everday, Im not sure. |
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I wish I had more information on the electric water pumps as for how long they last, but consider how long an electric fuel pump lasts in new cars, usually an easy 100,000 miles. Thats longer than I can say for mechanical pumps I have used, but it does cost about 10 times more to replace. One draw back of using the electric pumps over the older mechanical ones, is that a charging system failure would totally disable the vehicle. On an older car with mechanical pumps you could drive on battery power for quite awhile if the alternator dies. Another possable isue is the electric pumps usually don't give you much warning before going out. Usually the mechanical pumps would create some performance problems to let you know it was on the way out. |
#26
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The centrifugal water pump is identical in the electrical and belt driven pump. The power to drive the pump is from a different source. The only way a centrifugal pump can cavitate is because of a lack of fluid at the source. The probability of this happening in an encaspelated system with 16 PSI of pressure is nil. Poor coolant system designs that permitted air to be trapped in the system would cavitate at idle speeds when the impeller speeds were not high enough to move fluid, those designs have been eleminated in modern vehicle systems. Horepower is a measure of work, electrical work is measured in watts, any electrical motor heater\coolant fan draws a lot of current, this is not a problem with the proper alternator. The alternator is a constant output device, the amount of useage from the alternator is governed by the demand from the accesories and controlled by a regulator. If a 100 amp alternator is producing 15 volts that produces a constant 1500 watts. As long as this wattage is not exceeded all appliances will work efficently. The vehicle user should decide what is best for their application based on the excellent input generated in this thread.
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#27
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