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  • S14 DET or DE as temp swap?

    Since machine shops don't know how to machine, I'm thinking about a temporary swap. I wouldn't mind being able to push things, possibly with E85.

    Options are S13/S14 SR20DE or S14 SR20DET. The later being roughly twice the cost, but probably having $350-400 in parts I can sell off, so it's not all sunk cost.

    I have narrowed it down to these since they came with a 0.838 5th gear. Might as well get a trans with gearing I want to try out.

    The drilling and tapping of the DE block sounds annoying to try to not put a ton of shavings in it, but it's not a deal breaker. I should have a CAS and cool packs sitting around to run it with a spare S13 harness I have for a bit until I make my EMS-4 harness and run it with the AEM cas disk. This also allows me to get the EMS-4 up and going before putting a built engine in, so it's valuable development time with a temp engine IMO.


    Thoughts on which one? I don't know if the DE rods are weaker, which is a concern. Pistons as well? Will they die quickly at 400 rwhp even with E85?
    '18 Chevrolet Volt - Electric fun hatch for DD duty!


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  • #2
    Does drilling and tapping the DE block save you enough coin to develop that EMS-4 harness faster?

    If it's a 'temp' motor, I'd take the risk and spend as little as possible so the real end goal doesn't fall further behind.
    '95 240sx

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    • #3
      It's not so much a question of $$$ as it is time. I have all the stuff I need to toss the EMS-4 in. It's just a question of delaying having a running car while I have to mock up a harness. Versus I have what appears to be a very fresh S13 SR harness that I should be able to plug right in and rock and roll with my reliable tune.

      I can make the EMS-4 harness sometime later when I can measure everything out, trim it, then solder/terminate it in my spare time.

      That said, I'm guessing the SR CAS goes right in on the dizzy drive gear with no issues? I don't see why they'd be different, but Nissan has surprised me before.


      The DE makes me a bit wary that I'll nuke it the first time I push it over 350 rwhp, or I'll just be fighting detonation on track with 93 if I don't go to E85 soon. I don't mind turning it down to like 10 psi on track, which I'd think would be ok with soft timing on even 10:1, but who knows. Maybe the pistons are super weak?
      '18 Chevrolet Volt - Electric fun hatch for DD duty!


      DefSport Koni Sleeve and Spring Perch Buy!!!
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      • #4
        Originally posted by Def View Post
        I'm going to do the DET setup since I'm going to be side tracked and won't get to my EMS-4 harness for a while.
        Cool, glad you figured it out.

        I've never done anything more than set base timing on an SR20 (DET), I can't help you on the CAS. Is the DE not coil on plug? If not, just get the DET. Don't invest any more time than you need to on the temp motor. That's not the main project.
        '95 240sx

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        • #5
          hah - I guess that's a way to look at it.

          The DE has a distributor and old school wires. But the only reason I'm considering the DE is I have *ALL* (or at least 99.9%) of the stuff I'd need to run it on my existing ECU - which thankfully I haven't sold off yet. Although I did sell off my clutch stuff - damn you Ross! I'm hoping it won't be too much development work to get the 7.25" clutch working. I think I do have an Exedy Hypersingle sitting around somewhere though...


          I can't find any info on RWD DE vs. DET rods and pistons and their relative strength. Which is disappointing. I figured fools on here would know.
          '18 Chevrolet Volt - Electric fun hatch for DD duty!


          DefSport Koni Sleeve and Spring Perch Buy!!!
          http://www.nissanroadracing.com/showthread.php?t=5902

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          • #6
            The DE has 9.5:1 pistons if I'm not mistaken, along with higher top ringlands, which we both know isn't ideal for boost. I thought and am almost certain that the rods are different between the two engines, but I can't recall. I think the DET's are quite a bit stouter than the DE's. However, the cranks are identical between the two.

            I've read about people turboing the DE and not faring well around the 350 mark. I do not have any solid technical data to provide though. What are you going to be using the car for while the other motor is out? Why spend money on something you don't need?

            If you must have an engine to statisfy your needs until your other setup is done, I'd say go with the DE, you're going to save quite a bit of money over the DET. Keep in mind you'll need to tap the block for oil/coolant for turbo as well.
            VVL S14 on KW's...

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            • #7
              S14 DEs (what I usually see now, S13 engines are OLLLDDDDD now) are 10.0:1 compression.

              The car will be beat on flogged repeatedly on track. I don't mind running a little less boost, but I felt the car was ho-hum in speed at ~14 psi on a DET with cams (GT2871R), and I imagine the DE would need more like 10-11 psi to be halfway happy.

              Tapping the block isn't a big deal other than trying to get all the shavings out.


              The S13 and S14 CAS are the same right? I'm assuming I can pretty much throw an S13 DET harness on an S14 SR and have it run just fine with maybe needing to change something silly like the coolant temp sensor or the like. Or am I mistaken? I just don't have much S14 SR experience, only messed with 2 really.
              '18 Chevrolet Volt - Electric fun hatch for DD duty!


              DefSport Koni Sleeve and Spring Perch Buy!!!
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              • #8
                As far as I know the CAS are identical. The S14 has a different CTS, which also reads differently on the ECU/gauges. I'm sure there are a few wires that will need to be repinned as well.

                The S14 DE's have VTC as well, which I don't think your S13 ECU will run. Unsure of IACV/TPS/O2 sensor changes between those years.
                VVL S14 on KW's...

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                • #9
                  I'll run my S13 62 ECU and then use a window switch if I want to mess with VTC. I more want an S14 engine because S13 engines are pretty ancient now, and finding a decent condition one is getting more unlikely, and I want a 0.838 5th gear trans.

                  I'm guessing I can toss an S13 CTS into the S14 neck?
                  '18 Chevrolet Volt - Electric fun hatch for DD duty!


                  DefSport Koni Sleeve and Spring Perch Buy!!!
                  http://www.nissanroadracing.com/showthread.php?t=5902

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                  • #10
                    Yes, same thread pitch/size on the CTS.

                    IACV plugs and overall shape are different between the two as well as the TPS sensor plug now that I think about it.

                    However, an S13 throttle body is an upgrade over the 50mm S14 T/b anyway, so no big deal there.
                    Last edited by jr_ss; 10-01-2013, 02:52 PM.
                    VVL S14 on KW's...

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                    • #11
                      I think I've got an S13 DET throttle body somewhere... at least I hope I do. I've got 3 freaking stock intake manifolds!

                      I'm debating it still. I have a couple more weeks until I finish up my garage, then it's ordering time.

                      I also got a killer deal on a Thermal Arc 186 TIG. I was planning on buying that later in the year, but at about $400 off, it's hard to beat the deal. The place has mixed reviews, so I'll reserve judgement until it goes alright.
                      '18 Chevrolet Volt - Electric fun hatch for DD duty!


                      DefSport Koni Sleeve and Spring Perch Buy!!!
                      http://www.nissanroadracing.com/showthread.php?t=5902

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                      • #12
                        The CTS plug is different from the S13's, so swapping the CTS may be a bit more challenging. The center aligning mark on the CTS/Plug is offset on the S14's.

                        You'll also have to swap injectors, believe the NA motor has smaller CC injectors, but not 100% certain.

                        When I was in SLC for work, a guy onsite had a small portable Miller TIG. That thing was RAD. I looked into purchasing one, I think they were well into the $2k range, a little to steep for me at the time. Not to mention I have access to a TIG at the shop anytime I want. It's always nice to have the stuff at your place instead of dropping everything your doing, loading it up into a car and going out of your way to weld something small.
                        VVL S14 on KW's...

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                        • #13
                          I will be using an S13 harness, and my existing setup of 740 cc injectors, Z32 MAF, 2871R etc.

                          I'd like to think it could hold up to 300-320 rwhp on track and a bit more on the street, but 320 is probably the most it will make with stock cams. Which I think the DE has slightly more aggressive cams, so that would at least help make it not such a dog over 6k rpm.

                          I'm getting very different opinions, but I think I'm leaning towards the DE gamble just to save the cash. Used engines don't hold their value well, so the DET is just throwing money away for something I hope I'm not on more than 6 months or so.

                          I might go to 1000 cc inj and E85 sooner with the DE to try to keep 10:1 happy on track.
                          '18 Chevrolet Volt - Electric fun hatch for DD duty!


                          DefSport Koni Sleeve and Spring Perch Buy!!!
                          http://www.nissanroadracing.com/showthread.php?t=5902

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                          • #14
                            Just curious what you ended up going with? I have an S13 SR20DE, if you have any questions still I'll try my best to help.

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                            • #15
                              I got a great deal on an S15 SR20DET. Still have a few bits to sell off, but it's down to close to $1k out of pocket so far.
                              '18 Chevrolet Volt - Electric fun hatch for DD duty!


                              DefSport Koni Sleeve and Spring Perch Buy!!!
                              http://www.nissanroadracing.com/showthread.php?t=5902

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