Datsun Roadster Forum-311s.org

Spriso has given all of us a head start on the SR20 swap w/his DVD pictures with the kit, and including the FSM. Yet I still have some questions that might be good to post so once I get solved, others searching will have as well. An earlier thread helped answer some of these questions on vacuum lines (viewtopic.php?p=288038#p288038). I'm at the point of putting together my own intake setup and trying to figure out the lines/hoses. My own situation is different in that I'm converting to a dead-head fuel rail, that will come in from the back, and I won't have the return fuel line. Also, I'm going to be running speed density w/MAP rather than a MAF; don't know if that will make a difference. In the attached pictures, I marked 10 hoses/ports/lines that I need to figure out, and here is what I think needs to be done based on this thread and other pictures--appreciate any correction or filling in.
#1: vacuum ports; these just need sealed off as not needed.
#2: AAC: need to connect to intake tube in front of throttle body
#3: Oil Vent (?); connects to valve cover
#4: ?, but seems to be plugged from Spriso's pictures (EDIT: Michael informed me that this is a brake vacuum--it is plugged)
#5: Throttle body coolant line? How does this connect to the heater hose/thermostat setup? Do we even need to connect this (I know other engine swaps where this is not used).
#6: Heater hose line coming off the lower intake (for temp sensors); this is larger and I'm not sure how it connects to the heater hose system.
#7: Heater hose, not sure what it connects to (#6?, #5?)
#8: heater hose output to heater?
#9: heater hose return from heater?
#10: Vacuum line to fuel pressure regulator (not needed for my dead-head system so I'm capping).
I would especially love to see how people connected their heater hose lines to simplify the install. Anybody running silicone heated hose? I'd like to have the longer lasting stuff if possible. Thanks for confirming/denying/adding to what I have.

3 and 4 probably PCV valve line. That depends on how you are venting the valve cover and crank case. I always run one.
Are you running a heater in the car? That may change if you are "looping" the heater hoses or not.
Water to the TB probably depends on where you live as far as cold climate. Some run it and some don't.

There are others here that know more than I do about the S14 NA engine.

I'm pretty sure now that #7 is part of the throttle body warming circuit, as the fatter part of the hose is a cushion, and the actual hose is the same as what's on #5. I would guess it connects to the open other end of that throttle body heating circuit (where I don't have a number), and #5 goes into something else, not sure what. I'm hoping someone with an SR20 S14/S15 swap done will be able to show how the heater hose setup worked.

Edit: I was able to find the other part of the hose from my original disassembly 4 years ago...now I can see the heater hose setup with the exception of the return (or supply) to the throttle body. Getting closer to figuring this out.

Edit #2, the other throttle heating circuit comes out of the lower intake near the temp sensor. I don't know whether it makes any difference in the flow director of the throttle body; if it does, appreciate someone piping in.

I think I'm on my last question. Which of the two heater hose lines is to the heater core and which is the return? I need to put my valve in and it needs to be in the direction of the flow (or at least I have to know the flow direction even if I mounted it on the return side). My guess is its the line closest to the block based on how I think I should be reading the FSM but I'm not sure, picture of FSM attached. Anybody know?

Jeff:

The hose closest to the engine is what I've got connected to my heater valve. I don't remember if I've ever used my heater so no guarantees.

Shannon

Wanted to double check this heater hose connection and another site seems to confirm my suspicion and Shannon's practice that coolant line closest to the block is the supply to the heater core, with the other going into the thermostat the return. Now I can put my Vintage Air valve in.

"You want the line coming off the head. It feeds the heater core then goes back around to the thermostat housing. Under the intake manifold, it's the hard pipe with a small one coming off of it, looks kinda like a Y. The smaller hose off Y part goes to the thermostat housing also, so it can be a bit confusing if you're not following that coolant circuit diagram closely."
https://zilvia.net/f/showthread.php?p=6 ... ost6406342