SP3 coolant passages at rear of intake

Discussion in 'Small Block Tech' started by Fox's Den, May 20, 2017.

  1. gsjohnny1

    gsjohnny1 Well-Known Member

    doesn't matter to me, but maybe some one should ask the mopar racers why they tie the back ports together instead of jawing it to death.
     
  2. 300sbb_overkill

    300sbb_overkill WWG1WGA. MAGA

    You almost always crack me up when you post! :D



    Derek
     
  3. Fox's Den

    Fox's Den 355Xrs

    I have talked to gsjohnny and he gives it straight up it really makes sense and is a no brainer to hook the back to the front.

    He has a nice set up where it has a T between the back two and the line then goes back underneath the runners to a tube facing to the back of the engine. Our intake does not have this option his intake is home made.

    There could be a flow problem as Jim said there is the path of least resistance for water to flow.

    I would have to put the T at the fitting on the drivers side and bring it to the front to the other 3/4 opening at the front. But, from that T to the front the fittings need to get around the corner of the #1 intake runner, Hose will not make this bend around the corner. I will need to put in a extra fitting to get around the corner.

    Thanks for the input so far I think it is worthy to take advantage of this system just have to do it right.
     
  4. Mark Demko

    Mark Demko Well-Known Member

    The right rear port is how I had/will have again, hooked up.
    Heater worked fine, AND I had room for the Holley style fuel line.
    The front port is right in the middle of the fuel line inlet
     

    Attached Files:

  5. Jim Weise

    Jim Weise EFI/DIS 482

    I don't want to be argumentative, but we did do a lot of work with this in building manifolds for the 455 race motors that are filled. Since we reduced the volume of water in the block, the idea was to externally supply it from the water pump. Those external lines are cool water to the heads, not hot water from them.

    The initial guys that did it, welded nipples on the timing cover, TA eventually put pads on his cover so you could drill and tap them. I came in right around that time, in the early 90's with this stuff. Later on, in building tunnel ram intakes, we did try and add lines from the back of the heads to the water outlet, but that proved to be ineffective, if not downright counter-productive. More cold water entering the head from the rear resulted in cooler head temps.

    For a time, we had coolant flow meters on the dyno, and with or without extra return lines, water volume was very similar, and head temps were unchanged, when we focused on taking water out of the rear of the head. Only adding cold water back there made a difference.


    I would be interested in hearing the argument for externally bypassing the head.

    JW
     
  6. Fox's Den

    Fox's Den 355Xrs

    My thought was that the water would be pulled from the back of the heads to the front or say pushed by the water pump. I thought the water flowing in this motion would keep the heads at the same temp from front to rear. I guess I need to look at a chart that shows the flow of water thru the engine and see what happens to the water at the back of the heads. Or lets say, where does the water go from the back of the head. Does water flow to the back of the head and back to the front in a circle?

    The real way to do it is take each fitting and run its own line from the back to the front on each side so everything is even in its flow.
    My fuel lines will not interfere with the way I wanted to hook it up.

    It may Not be a good idea to pull the water from the back of the head and go thru the heater core then since this may cause a change in flow from that head and that may interrupt flow to the front.

    Maybe the right idea would be to connect the two rear together then go thru the heater core. But even this may create a flow problem going back to the front on the engine.

    Not looking for arguments on this just thought this was a good idea, I will watch and do a little more research.

    Thanks for your thought on this.

    Guy
     
  7. Jim Weise

    Jim Weise EFI/DIS 482

    Guy,

    Water is drawn in from the bottom of the radiator on the cold side via the lower hose to the water pump.

    The pump pushes water into the block on both sides, via the water passages in the timing cover.

    The head gasket keeps the vast majority of the water in the block as it travels toward the rear. The small holes over the sand clean-out passages are designed only to allow air to escape while your filling it. The rear of the gasket has the slot in it, that corresponds to the slot in on either end of the cylinder head (they go on either side that way) and the slot which is only at the rear of the block.

    Water travels from the rear of the block thru that slot, and up into the cylinder head.

    It travels back forward thru the cylinder head, where it picks up most of it's heat.

    At the front of the head, it exits thru the forward intake flange water port, thru the intake, past the thermostat restriction, and out the upper hose to the hot side of the radiator.

    With this in mind, and considering the fact that the system is full, and the actual restriction is the open thermostat, a restrictor in place of the thermostat, or the diameter of the water neck, running a line that basically by-passes the head really does not serve any purpose. The head is not the flow restriction, the restriction is farther downstream at the thermostat, and your by-pass is behind that.

    Now, if you added a couple hose nipples to the hot side of the radiator, and ran the hoses there, you might be able to by-pass the restriction and flow more water.

    But now the question becomes.. do we really need to do that? Does that help us, or hurt us?

    JW
     
    patwhac and Gary Farmer like this.
  8. 300sbb_overkill

    300sbb_overkill WWG1WGA. MAGA

    I would think that routing from the back to the heater core(for someone with that option) would help pull water to the rear faster perhaps slightly improving cooling in the rear? But possibly not effecting it either way?

    I have to agree with JW, to improve cooling would be to route pressurized cooled coolant to the rear of the block or heads pushing it to the front where it returns to the radiator. But probably not necessary for a pump gas street car with no block fill in it. Unless someone would want to run higher compression with pump gas it may be something to explore? Like the way the General did with the LT1 sbc with its reverse coolant flow that cooled the heads first so they could run 11:1 compression with cast iron heads with pump gas.

    Perhaps route the cooled pressurized coolant into the heater core to cool even more, THEN into the back of the heads for even cooler coolant introduced in that area. At the track, turn the heat on high when making a QM pass to keep the head temps even cooler.(brow guy here) With this setup the engine can probably get away with 11:1 static compression with 9:1 of dynamic and still be able to run with pump gas 91- 93 octane?

    Other than the above, just using the rear so you don't have the heater hose block your fuel line would be fine.:D



    Derek
     
  9. 436'd Skylark

    436'd Skylark Sweet Fancy Moses!!!!!


    if you read jws post the rear gets most of the cold coolant from the block. it gets warmer as it travels from the rear of the head forward. the reality is the front cylinders would be warmer, not the back.
     
  10. 300sbb_overkill

    300sbb_overkill WWG1WGA. MAGA

    Yes so the first sentence I wrote is wrong so probably not the best place for the heater core hose but probably wouldn't hurt a thing to hook up there. Forgot about the front being blocked to force coolant to the back of block before it gets to heads.

    But the water is getting warmed from the top of the hot cylinders before entering the heads at the rear. Running twice cooled coolant to the rear would cool heads even better. A good way to go with a Buick block filled to the top of deck, would be like having reverse coolant flow of cooling heads first. Probably not so much with an non-filled block because it may slow flow down from the front being forced to back and getting rammed with pressurized water.




    Derek
     
  11. 436'd Skylark

    436'd Skylark Sweet Fancy Moses!!!!!

    The coolant would not be twice cool. Water would be flowing out the back of the intake manifold not into it.



    No disrespect intended to anybody here. But you guys are trying to solve a problem that does not exist.
     
  12. Mart

    Mart Gold level member

    With the windows closed in summer heat! NO thanks! :eek::po_O:rolleyes::D
     
  13. 300sbb_overkill

    300sbb_overkill WWG1WGA. MAGA

    Twice cooled would be coolant from pump routed to heater core then to the back of engine. I wouldn't do this unless the block was filled and I wanted to extra squeeze running pump gas, so I probably wouldn't do this at all.

    Yeah I would agree with in the bold statement.:cool: Just having a bit of fun with the subject.


    Derek
     
  14. 300sbb_overkill

    300sbb_overkill WWG1WGA. MAGA

    If one were to do this to be able to run more squeeze, it wouldn't be hard to re-route the heat to the outside of the car. :p:D


    Derek
     
  15. 436'd Skylark

    436'd Skylark Sweet Fancy Moses!!!!!

    the coolant would flow out of the back of the intake. it would be an outlet, not inlet. you wouldn't be able to force the coolant backwards. it would only flow out there not return from the heater core.
     
  16. 300sbb_overkill

    300sbb_overkill WWG1WGA. MAGA

    Not with a block that has cement fill where the coolant use to go in blocking the entrance. The timing cover would have to be drilled and NPT tapped for fittings for the coolant to exit out the top to be plumbed to heater core then to rear of heads.

    Oh, and those intake coolant ports go directly into the head's rear coolant holes.


    Derek
     
  17. 436'd Skylark

    436'd Skylark Sweet Fancy Moses!!!!!

    re read and edited. what sense would that make? with all that engine work why would anyone run a heater core.
     
    Last edited: May 25, 2017
  18. 436'd Skylark

    436'd Skylark Sweet Fancy Moses!!!!!

    no kidding.
     
  19. blyons79

    blyons79 Well-Known Member

    This has been an interesting thread. (I'm in the process of replacing a cracked head) My takeaway is: if you want to cool the heads, have an optimized cooling system. Don't reinvent the wheel...put a better tire on it and balance it....i.e....have a quality radiator, fan(s) and water pump. Hell...keep the RPMs down. Run external trans and oil coolers.
     
  20. 300sbb_overkill

    300sbb_overkill WWG1WGA. MAGA

    Yep that's exactly what to do for a mostly street driven car. :cool:

    Leave re-inventing the wheel to the trailer queen/drag queen race cars. :D


    Derek
     

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