No announcement yet.

240z project car motors

  • Filter
  • Time
  • Show
Clear All
new posts

  • 240z project car motors

    alright i've got some questions for you nissan-loving gearheads. I miss my 510 so i've decided to build another datsun, but this time a 240z. I'm trying to decide what motor to put in it and i have a couple ideas. My first thought was sr20. lightweight, makes for a near perfectly balanced z, good power. but i'm also considering building a high comp, N/A RB series motor. maybe heavier, but keeps the origional inline 6 design and would sound beautiful, especially with ITBs and velocity stacks.

    so my questions are:
    -what would be the most powerful N/A RB engine to drop in there?
    -pretty sure RB26DETT runs ITBs from the factory, correct me if i'm wrong. but would it be possible to use that ITB setup on an N/A RB motor?
    -are there any aftermarket kits that run an ITB setup designed for an N/A RB motor?
    -are there any engine kits or aftermarket pistons that boost the compression ratio to get as much power as i can without turbos?
    -how much power could i expect from a built N/A RB motor?

    last question is a little off topic:
    -what type of cams and what conditions are necesary to make a motor spit fire from the exhausts? (I see built race cars spit fire between gears and my heart screams 'I want that!'")

    any help would be greatly appreciated. thankyou.

  • #2
    If you want N/A power in your Z and good weight distribution get a


    • #3
      naw i'm not feeling a V8. i've got my mind set on the RB now. thanks though. so does anyone have any info?


      • #4
        There was a N/A RB26 offered on a very limited basis. I am not interested in N/A so I never really looked up much info on it. I want to say it was about 210 hp.

        If you took a "normal" RB26 then you would need pistons at the least to raise compression. You may have to go in and change combustion chamber volume. The stock RB26 cams are pretty small.

        The RB is individual throttle body. The plenum/collector, MAF car.


        • #5
          get a RB30 block from Australia (they came in some Holdens, sohc) put a rb25 head on it, & rb26 itbs

          or go straight gangster & ditch the EFI for some weber DCOE 45s

          3 litre, dual cam, crossflow, awesome...
          what more could you ask for

          would make the swap a whole hell of a lot easier too


          • #6
            RB30 like this ?


            • #7
              Honestly, unless you could lay your hands on one of those exotic (and bloody GORGEOUS) 2.0L DOHC straight-sixes from the Z432R Fairlady, I wouldn't swap out the L24 for the life of me. It's too sound of an engine!

              The biggest problem with the L24 - in my experience - is breathing. The old siamese port cylinder head can only do so much. Thankfully, 30+ years of development by the aftermarket has led to beautiful alloy crossflow cylinder heads that flow like a sonuvabitch, bringing peak power up tremendously.

              Believe me, us MGB folk know a thing or two about aftermarket cylinder heads!

              I know of more than one SCCA competitor who through careful parts selection (mostly out of the far superior American aftermarket for the L series engines) who's pulled 350+ hp out of their 240Z. Not to mention, displacement bumps from aftermarket replacement L26/28 cranks and a nice .030 overbore with a set of Wiseco domed high-top pistons never hurt anyone, either.


              • #8
                ok first we need to address your goals with this motor.
                is it going to be street driven?
                a track car?
                whats your budget?
                are you looking for power & reliability
                or are you looking for bling factor?

                the way I see it, if you're looking for (realistic) power & a dead reliable motor build an L series.

                it'll be much less work, you can actually find replacement parts when they break, & people have been working these motors for 37 years, so theres a wealth of information to be found.

                plus I can tell you, theres nothing in the world like a hi-comp l-28 at full song

                anyway, any questions you have about damn near any swap possible into a
                S30 chassis can be answered at

                oh & octagon: the 2.0 twin cam motor you're talking about is the S20
                & as for aftermarket heads, keep dreaming. OS Giken built a dual cam head in the 70's (called the TC24-B1) but even then they were $15,000 or so. now they're almost impossible to get ahold of.

                on the other hand, there are a few people (search on hybridz) working on dual cam heads made from cut up KA24-DEs so there may be more options in the future.


                • #9
                  Heh, guess I've been disproven. Since alloy crossflow heads are so prevalent in the MGB world, and I'd heard rumblings of the same sorts of conversions in the Datsun camp, I'd figured it was just as common.

                  And believe me, it's a DAMN common thing to run across a crossflow head on an MGB since so many people are still casting them. The old siamese port on the 1800 (complete with shared exhaust port for #'s 2 and 3) is piss-poor for power.


                  • #10
                    I wish that was the case.

                    but sadly , us mere mortals are stuck with the intake & exhaust on the same side...


                    • #11
                      Stroke the factory motor and slap on some triple webbers.


                      • #12
                        the downside of strokers is they're not reliable at higher RPMs

                        though if its gonna be solely a street car its a good option.


                        • #13
                          Originally posted by dori ninja View Post
                          the downside of strokers is they're not reliable at higher RPMs

                          though if its gonna be solely a street car its a good option.

                          The advantage is more torque at the low end, so you don't need to beat the crap out of your clutch.


                          • #14

                            I just see it as a large investment for not much more.

                            also I think its funny that this thread is still rolling & the person looking for advice is MIA haha