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#21
03-11-2014, 08:17 PM
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Glad to Help,  Larry S.
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#22
03-12-2014, 08:19 PM
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My block decks have 2 x 5/16", 3 x 3/8", and 2 x 7/16" holes per side. The holes in the heads match or exceed that. Marcella manifold has 4 x -10 AN inlet and 1 x -20 outlet going into 1.5" rad hose. If I tee -8 AN from rear and -6 AN from center into -10 AN inlet and another -10 AN from front to other -10 AN inlet per side, I think I will create enough positive pressure and have enough flow for optimum cooling.
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#23
03-13-2014, 09:07 AM
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Only Seven Holes in the Deck?
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For Example: - The MR-1 Block has 11 coolant holes. - The Factory Block has 10 coolant holes. - The KRE High Port Head has 14 coolant holes. - The Cometic Head Gaskets that I have here have 15 coolant holes. - The Solid Copper Head Gaskets that I have here have 14 coolant holes. I'm very concerned about the number of holes and the placement of those holes in your block's deck surface. The number of holes, their placement and their sizing is critical. They determine where the coolant enters your cylinder heads. If they're too few or too small then the water pump will pressurize the block and not the heads. If the restriction to coolant flow is greatest at the deck surface then the pressure will be generated in the block where you need it the least. The Meziere Pump, is it the Standard 35 GPM Pump or the H.D. 42 GPM Pump? Now is the time to correct all of this while you're getting ready to swap cylinder heads. So don't dismiss it. Any Pictures? Thanks, Larry S.
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#24
03-13-2014, 08:37 PM
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Sorry, mistyped the number of 5/16" holes. There are 5 per deck. Total of 10 holes per deck as per factory block dimensions. See attached drawing. The heads have more cooling holes.
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#25
03-13-2014, 08:39 PM
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Standard 35 GPM Meziere pump
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#26
03-14-2014, 11:52 AM
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Good Deal...
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It shows what the Pontiac Engineers were doing to ensure that the coolant would tend to make it to the rear of the block and cylinder heads. Notice that the size and placement of the holes are biased towards the exhaust side of the block and cylinder head and also notice that the holes get progressively larger as they reach the rear of the block. This was their way of getting the greatest coolant volume into the exhaust side of the cylinder heads and to ensure that sufficient coolant would make its way to the rear of the block and heads. Anyone that drills their own holes in an aftermarket block should seriously consider the number of holes, their size and their placement. Everything that we do or recommend relates to improving upon what the factory was trying to accomplish. Yes, they were biasing the coolant flow towards the exhaust side and towards the rear of the block, but that doesn't ensure that the coolant is actually circulating readily through all of the various cavities in the cylinder heads and block. There needs to be properly sized and positioned exit paths for the coolant to pass through to ensure the elimination of trapped air and to ensure a proper volume of coolant for "Effective Cooling" purposes. In an aftermarket block that comes dry decked, the customer or engine builder needs to consider whether or not the engine is a street car application with a thermostat and heater core or a racing application without the thermostat or heater core. In a racing application the location and sizing of the holes through the block's deck surface can be much more symmetrical front to rear. Although I'd still drill larger holes along the exhaust side of the deck and smaller holes along the intake side of the deck. Then you can control the coolant flow from the front, the center and from the rear with the coolant exit fittings in the cylinder heads. Thanks, Larry S.
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#27
03-14-2014, 05:51 PM
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I dry decked and reverse cooled my 421 turbo combo,water enters the inlet manifold crossover from a SBC electric pump,goes through the heads and out of the back of the heads via -10 braided lines into the back of the block, it travels through the block and then exits from holes I drilled in the front of the block via -10 lines into the filler neck. The filler neck has a 5/8" restrictor in there to purposely create a restriction after the block/heads ,as this will help to pressurize the block and heads. I believe the system is called a 2 pass system. It has a -6 line from the top of the water pump to the crossover to purge air, I've not had any problems with airlocks and it will sit and idle all day at 140-160 F, it does go up to about 180 F at the end of a run. I tapped and plugged all the block deck and head coolant holes and use solid copper head gaskets,and the factory block is also 3/4 filled.
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#28
03-14-2014, 08:03 PM
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Here's what I'd Do....
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At Johns Manifold use Two (-10 AN X -8 AN Male Adapters) for the Front Lines and Two (-10 AN Adapters) for the Rear Lines. On each Cylinder Head, Run the Center -6 AN Line and the Rear -8 AN Line into a "Y" or "T" Fitting with a -10 AN Outlet Line that'll run to the other Two Ports in John's Manifold. Note: One of the Manifolds that we're creating eliminates the need for multiple adapters to get this done under the intake manifold. It'll already have the -6 AN, the -8 AN and the -10 AN Fittings made into it. So, Here's what you'll end up with: Two -8 AN Lines (Front) and Two -10 AN Lines (Rear) at John's Manifold. (That's Approximately the same as the Flow through a 7/8" Hole.) Theoretically Speaking, the Water Pump Outlet Volume should Exceed the Volume of Flow through that 7/8" Orifice and therefore be Capable of Creating a Positive Pressure in the Cooling System. Keep in mind that whenever the coolant is forced to make a turn or flow through a hose or through a "T" or anything of this nature, the resistance to flow increases. This means that even if you calculate all of the various orifices to equal a specific "Total Orifice" size, the actual coolant flow will be less and the overall restriction will be greater. Therefore even if the flow capacity of the Water Pump is "EQUAL" to your calculated "Total" orifice size, which means that "Theoretically" it wouldn't create pressure, in fact it would still create pressure. I hope that all makes good sense... BTW, In my original lengthy post, I meant to say 35 GPM Water Pump in my examples and not the 30 GPM that I listed..... Woops.... Larry S.
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#29
03-14-2014, 09:20 PM
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If you are reverse cooling a Pontiac its best to know how the factory addressed it... Like wise, learn what changes they made in 1960 to ensure success with conventional cooling scheme. The infamous "421 mod" was actually present in 55-59 blocks. 60-up blocks on the upper front deck the 1st two holes are blocked to prevent water short-cutting to crossover. http://www.pontiacsafari.com/EngineCooling/index.htm (excerpts from the 55 and 60 factory shop manuals) http://www.pontiacsafari.com/55/ShopManual/index.html (55 shop manual) If running "dry deck" for racing... cooling the heads 1st is the better choice... the block simply doesnt need as much cooling as the heads do. From the 55 shop manual ... Quote:
I can think of no better example than 2-stroke liquid cooled snowmobile and motorcycle engines... I've not seen one that didnt cool the head 1st. All that I've personally seen, flow water through the heads and the cylinder water jackets simply gravity fill. Leaving convection/vibration as the only way back out. (2-strokes are not efficient and generate a lot of heat because of their inefficiency. Yet they make a bunch of power to ci and their cooling scheme keeps things in control) 55-59 Pontiac reverse cool scheme... the large majority of water flowed through heads 1st and back out to radiator and only two 1/2" holes on block face gave some circulation path for block "flow"... and that was primarily to serve as thermostat bypass during warm up! Water mostly just "fell" into the block just like the modern 2-strokes I just mentioned. Page 6 A3 http://www.pontiacsafari.com/55/Shop...ubrication.pdf is worth reading. Last edited by BruceWilkie; 03-14-2014 at 09:30 PM. |
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#30
03-15-2014, 09:54 AM
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Reverse Flow Cooling...
The Obvious Benefits of Reverse Flow Cooling cannot be Ignored.. In an "Extreme" Racing Effort I'd be willing to say that anything other than Reverse Flow Cooling would be a Mistake.
As Bruce has been mentioning, Reverse Flow Cooling a Pontiac Street Car with a Thermostat and Heater Core would require some creative cooling system plumbing to say the least. As he has mentioned, reverse flow cooling was the norm for a Pontiac until it was eliminated in favor of the current cooling system configuration. Probably, as Bruce has mentioned, due to the cost or the complexity of the original reverse flow cooling system. Here's some Insight into how I'd accomplish Reverse Flow Cooling a "Wet Deck" Extreme Effort Racing Engine. 1) Start off with a 55 GPM External Water Pump. (With Two -16 AN Outlets.) 2) Fabricate and Install Three -10 AN Lines to Each Cylinder Head. (One in the Front, One in the Center and One in the Rear.) 3) Fabricate Two Coolant Manifolds with a -16 AN Inlet and Three -10 AN Outlets. (Plumb each Manifold to One Outlet from the Pump and to the Three Hoses going to each Cylinder Head.) 4) Starting with a "Dry Deck" Block, I'd Drill through the Deck, in the Appropriate Locations, with the Appropriate Size Holes/Orifices. (This would depend on the valve layout. E-I-I-E-E-I-I-E or E-I-E-I-I-E-I-E.) 5) The "Final" Outlet from the Block (The Radiator Inlet) would be Sized to a single -20 AN Fitting/Hose. (A Slip on Hose Fitting or Restrictor that had an Inside Diameter of Approximately 1" would also be Fine.) One more thing.... For the Guys Running Methanol and Especially Injected Methanol... (Relating to Drag Racing Applications Only...) My biggest concern would be eliminating air pockets in the cooling system passages. A high volume 55 GPM pump and large hoses and fittings is not really necessary. Heck in many cases a radiator fan isn't all that necessary (Except for Bracket Racing where you need to go round after round without a cool down period). BUT, a well designed cooling system that flows "pressurized" coolant through ALL of the passages effectively and efficiently is still of great importance. So a 35 GPM pump with "Standard Flow" cooling and smaller coolant lines would work just fine in most applications. Jusy My  Larry S.
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---------- http://www.pas4performance.com Proud to Say, "Made in the USA" ---------- Last edited by LMSRACER; 03-15-2014 at 10:06 AM. Reason: Calculation Error |
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#31
03-15-2014, 10:13 AM
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This is a great thread Larry!!! Thanks for taking the time to contribute and expose your knowledge. The information you have presented here is priceless.
Don Johnston DCI MOTORSPORTS INC. 330-850-5050 shop 330-628-3354 cell Designer of the DCI Tiger Heads and the NEW DCI Ram Air 5 Heads !!!!! |
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#32
03-15-2014, 11:12 AM
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Larry
When will your manifolds be ready for selling?
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#33
03-15-2014, 11:51 AM
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Dry Deck Block with Reverse Flow Cooling..
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I get alot of E-Mails and Calls about this subject so I thought that I'd post some information here........ Here's my thoughts on Reverse Flow Cooling a Dry Deck Block... I'll give two options depending on the flow volume of the water pump to be used... Option #1 Flows ALOT of Coolant through the Cylinder Heads... Option #1: 55 GPM External Pump. (Outlined In Order of Flow Direction...) 1) Two -16 AN Outlets at the Pump. 2) Two Fabricated Coolant Manifolds, each with a -16 AN Inlet and Two -12 AN Outlets. 3) Two -12 AN Inlets in Each Cylinder Head. One in the Front and One in the Center. 4) One -16 AN Outlet at the Rear of Each Cyliner Head. 5) One -16 AN Inlet at the Rear of Each Cylinder Bank of the Block. 6) One -20 AN "Final" Block Outlet/Radiator Inlet at the Front of the Engine. (A 1" Inside Diameter Slip On Hose Fitting or Restrictor would also work fine.) Option #1 is tough to do because of the size of the lines and packaging/fitting all of that around the intake manifold and rear of the block. A "Front Drive Distributor" and a Belt Drive System makes it much easier to accomplish. Option #2: 40 GPM External Pump. (Outlined In Order of Flow Direction...) 1) Two -12 AN Outlets at the Pump. 2) Two Fabricated Coolant Manifolds, each with a -12 AN Inlet and Two -10 AN Outlets. 3) Two -10 AN Inlets in Each Cylinder Head. One in the Front and One in the Center. 4) One -12 AN Outlet at the Rear of Each Cylinder Head. 5) One -12 AN Inlet at the Rear of Each Cylinder Bank of the Block. 6) One -16 AN "Final" Block Outlet/Radiator Inlet at the Front of the Engine. (A 13/16" <0.8125"> or 27/32" <0.84375"> Inside Diameter Restrictor or Slip On Hose Fitting would also work fine.) Let me make a Notation about Hose Fittings and their Dimensions. The flow volume from one fitting size to the next, for example a -8 to a -10, changes greatly. At first glance a -8 to a -10 is a 25% increase in flow. That is incorrect, it's actually a 51.48% increase. From a -10 to a -12 is a 61.5% increase in flow. From a -12 to a -16 is a 89.62% increase in flow. From a -16 to a -20 is a 65.3% increase in flow. So, whenever you design your cooling system for flow volumes and pressure, there's always going to be a certain amount of "Close Enough" or an "As Good as it's going to get" going on. Unless you "Engineer" ALL of your own fitting and hose dimensions, you'll be confined to working with what is available in the industry. Just keep in mind that you want the water pump to create a "Positive" cooling system pressure in the heads and in the block. If you size your system's hoses and passages too large, the water pump will never create a positive pressure. Where that positive pressure is located depends on where the restriction is located in your system. Remember that greater restrictions (Smaller Orifices) increase the system pressure and decrease the flow volume and reduced restrictions (Larger Orifices) decrease the system pressure and increase the flow volume. When using an Externally Mounted Water Pump, make sure that the pump's outlet lines are large enough that they don't restrict the coolant flow at all. Creating a Positive Pressure in the Water Pumps Outlet Lines before they ever reach the Engine not only Reduces the Water Pump's Outlet Volume, it puts an unnecessary strain on the pump motor. One Last Note: All of the Fiiting Dimensions that I've used for Calculation are Published Aeroquip Dimensions. Others may vary somewhat... Thanks Again, Larry S.
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#34
03-15-2014, 12:05 PM
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Coolant Manifolds...
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I hope to have several new items to show within the next four to six weeks. I hope that you can wait because it'll make plumbing the lines under your intake much neater and much more affordable. We're designing the manifolds to use "Push-Loc" style hose and fittings which eliminates four of the six hose ends under the intake manifold. The manifolds are going to have the Push-Loc fittings machined into them so that NO additional fiitings will be required for the Push-Loc hoses. Shoot Me an E-Mail @ oprecisionautom@carolina.rr.com and I'll contact you with updates as they become available. Thanks for the Interest, Larry S.
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#35
03-15-2014, 05:53 PM
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Great thread Larry,
In an effort to combat the cooling issues with our E heads, we conducted a rather clumsy but effective experiment. Running dry decks, we split the cooling system into four zones, using an external Meziere pump. The left and right sides of the block got -10AN lines in the front and -10AN out the rear. We introduced water into each head with two -10AN lines below and to the sides of the center two exhaust ports. (We wanted to put the coldest water into the hottest area). Then three -8AN outlets on the intake sides of each head. The pairs Y together under the intake manifold and join into a 4-into-1 water manifold out to the radiator. See attached pics. Other changes made to the motor were: Dropped compression from 12:1 to 11:1, changed intake rockers from 1.6 to 1.7 ratio and changed carburetor (same size). We expected a drop in power with the lower compression, but actually picked up 20 HP over our previous best. I cannot say that the cooling changes accounted for all of that, but it surely helped. Dick Fulton |
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#36
03-15-2014, 10:20 PM
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Heres my planned layout... I'm using a 59 timing cover and pump so I think I will have flow and pressure enough(yeah its heavy but trying to add a nostalgic look to this yet modern too, as I'm running serpentine belt system)... I did some test drilling on a scrap 6x along the valve cover rail... I've decided it would be beneficial to mimic the "sprinkler" tubes of the early heads. They directed coolant to the valve guide areas and exhaust ports before flowing back across head to the crossover. New style heads cannot accommodate the internal tube so instead of just 3 inlets like you propose I'll have NINE!... One for each valve and one in front and above the center ex bolt boss. I drilled as close as I felt comfortable to the exhaust ports/valve area and the drillings for the intake valve areas are pretty much in line... center hole at bolt boss had just enough room to clear boss and not interfere with valve cover. All the holes are slightly angled to avoid valve cover interference. The holes are just below the valve cover rail. Nine 1/2" holes that accommodate tubes 1/2" od with 3/8" id... total area @ same as water pump outlets. These 9 tubes will go into a rail type manifold(same concept as efi rail) with same inlet ID as pump outlet. Water can exit at head ends on manifold face... Its crowded by the distributor and plumbing to those rear holes on the manifold face of the heads can be challenging...however the manifold flange can be extended(welding) with a block of aluminum to cover the hole then drilled/tapped at a more favorable angle. Due to my timing cover design, dry deck cooling through block might best be done by entering from the side just below the center head bolt boss and exit out the ends with coolant fed to inlet from a separate remote pump. Keep in mind the heads need far more cooling capability than the block does, but coolant entering at center bolt boss can only help IMO However... I think with a bit of creativity I can run wet deck with very low risk of water in cylinders should a head gasket fail. Small counterbores around coolant holes in deck and head, with nylon or metal o-rings and "Right-Stuff" sealant would likely be near bomb proof. That sealant would allow enough stretch for amount of lift the heads might see at high power. (I "glued" a rubber cap on a 1/2" pipe with Right-Stuff and at @ 100 psi the cap remained on the tube. NO clamp!) A lot of extra work...probably way overkill... but keep in mind, mine is a twin turbo build and intention is to be able to drive most anywhere and race.(Drag week...perhaps! Drive to Norwalk from TN, race and then drive back? Thats main goal!) |
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#37
03-15-2014, 10:34 PM
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Thanks for Sharing those Images....
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I appreciate the images and I appreciate you sharing that experience. When I'm telling folks how they should consider plumbing their engines for maximum benefit I can sense them thinking, DO WHAT? "That's just Overkill" Isn't it?... There's No Doubt in My Mind that your Plumbing Design Worked Very Well........ Thanks Again Dick and BTW, that's one Awesome Firebird...... Larry S.
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#38
03-15-2014, 10:50 PM
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You've got a good understanding...
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We've talked before about your cooling system ideas and I know that you've got a good grasp on what you intend to do. I think the biggest hurdle to any "Twin Turbo" "Street Car" is available underhood space. Available Real Estate if you will... As Dick Illustrated in His cooling system layout, the plumbing can get very busy very quickly. Here's an Example: I recall a conversation with a GM engineer as a young man over the design of an A/C system in a particular Z28 Camaro and it's inefficiencies. I boldly asked why the A/C system didn't perform any better than it did. Why not use a larger A/C Condensor, a larger Evaporator and larger Outlet Vents. His answer was the obvious answer.. Packaging.. Available Space.. He elaborated by saying that the individual engineering teams responsible for each system on a vehicle are always struggling for additional space for their particular systems. The end result is a vehicle built with a long list of compromises. We too have to make the same compromises at times. There's only so much available Real Estate. Thanks Bruce, Larry S.
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#39
03-15-2014, 11:14 PM
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Mechanical Versus Electric Water Pumps..
Here's a bit of Information that some folks may be unaware of.
Mechanical/Belt Driven Water Pumps can actually pump a greater volume than many of the available Electric Water Pumps. In Fact a High Volume Belt Driven Water Pump can actually suffer from Cavitation at High Engine Speeds (Over 6000 RPM) unless you do something to slow it down. A change in the Crankshaft and Water Pump Pulley Diameters is how it's done. BUT, that same High Volume Pump doesn't pump much volume at low speeds, especially while the engine is idling. If you change the pulley diameters to slow the pump down to keep it from cavitating at high speeds, then the volume it pumps at low speeds becomes even less. This is where an Electric Water Pump really shines. It pumps the same volume ALL the time. Therefore, in a High Performance Street Car Application, a drop in engine coolant temperature during extended idling or low speed cruising conditions when switching over from a Belt Driven Pump to an Electric Pump should be expected. ** NOTE: When using an Electric Water Pump in a Street Car, there will be a Small Change in Pump Volume as the Engine Speed Increases due to the Increase in your Electrical System Voltage. The Alternator Output (Amperage & Voltage) will Increase as the Engine Speed Increases and this Increase in Voltage will Increase the Speed of the Electric Water Pump to a Small Degree. Thanks, Larry S.
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#40
03-16-2014, 04:31 PM
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Realestate in a 3rd gen is very tight in some places yet better than Debs 69 in other spots... Steering shaft, steering box, and brake cylinder are definately friendlier... lower control arm mounts crowd things a bit there but having struts I dont have as much crowding as earlier f bodies. My crank and pump pulleys(Crown Vic) are going to run the pump slower than the original 59 arrangement... my altenator is the 105 amp stocker from the efi v6 the car came with... fairly small diameter pulley so it should do ok. My pump outlets dont allow my late 60's mount pieces. I fabbed a plate for tensioner and idlers from the ford that mounts over water pump using longer bolts to sandwhich the pump... plus spacer tubes between plate and timing cover for added plate support... Pretty compact so far. Very good belt wrap too. I need to cut another plate and see if I can accommodate the original gm power steering pump. (looks doable)
I do need to mock motor back in place to check more than a few things. unfortunately one area of abundant space is in the nose... the last place I want to add weight. As the weather gets better I'll start takin pics and post them. Some early 4 bolt pumps used an impeller that appeared backwards but still ran in normal rotation... I believe it was used to cut down on cavitation... I'll obtain one and test both styles... If neither work well then remote electric(s) may be my only salvation. |
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