Jump to content
SAU Community

Recommended Posts

Gday all, i just have a question. My mate and i both have 180sx and both have RB20's in them. Mods wise they are very similar in that there isn't really any. But when we are travelling at similar speeds are revs are very different. E.g when im doing 100km/h my car reads out that im doing 4500rpm while my mate at the exact same speed is only doing 3500rpm and they are both in 5th gear. Could anyone tell me the possible reasons for the difference in revs and could this be a problem.

Link to comment
https://www.sau.com.au/forums/topic/36017-whats-the-reason-for-the-difference/
Share on other sites

im sure he knows what engine he has :D

they both got swapped for rb20's by the sounds of it. Sorry i cant help ya mate

yeah youd think so, but he said he and his friend have no mods.

why would you go through the effort of swapping the SR20 for the RB20 anyway? If you were going to swap to an RB you would at least go for the RB25.

Just to check that the tacho isn't wrong (as 1000rpm seems like a huge amount more for a 4.3 diff over a 4.1 one), do the engines sound the same when they cruise at that speed? I mean does your one actually sound like it's doing 1000rpm more than his? Since yours is slower, it does sound like your diff isn't some super high ratio one.

Im not the most knowledgeable when it comes to the mechanical side of cars, but can someone please explain what the difference is with the diff ratio and how it effects the car. Is it related to the gear ratio. Im sorry if this is a dumb question but i don't really know. Tah

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • Just had this happen to me too.  R32 GTR.   Also broke "just before going out onto the track" - someone up there is looking out for us... Very scary since I was about to do a narrow street course with zero run-off and curbs everywhere. Many people on here upgrading to billet uprights and R35 bearings?   Or buying new OEM knuckles?  I am not keen to replace with another s/h 30 year old fatigued part.
    • Top off with distilled water and see what happens. If you keep losing coolant then you know to start looking.
    • Nope.    Grab a varex and turn it down as you get close to home, win win? 
    • So, I've had my V36 for about a month now and have already copped an "excessive exhaust noise" notification from QLD TMR, reported by someone in my local area. It's a twin as per the original, and can have a bit of a throaty note to it when idling cold 😄 and if I do get up it a bit, it can be noisy, but it did pass a roadworthy inspection before sale, so.... ... but in the interest of being a good neighbour, I do want to quieten it down a bit. Is anyone here running a quiet aftermarket cat-back on their V36 or 370Z? And the big, bold question: does an aftermarket cat-back really make much of a performance difference on these cars?
    • The wiring diagram for the R33 RB25 is freely available, and is essentially the same same as most other RBs (just with differences as to which pin # does which job). To get the ECU to power up, you just need to provide power to the ECCS relay, and have the other power feeds that come in from the top left of the wiring diagram (wrt the ECU) that give perma power to the fuel pump relay, the ECU itself, etc etc, all connected. When you put power on all these it will just come to life. It's pretty clear from the diagram what needs to happen. Just follow the lines from the 12V + supply stuff in the top left over towards the ECU. I've even posted snips of such diagrams (not for vanilla 25, I think for Neo and 26) to various threads here in the last few months, talking about what it takes to get the fuel pump and FPCM up and going. Search these up and they will help get you started on doing the same with the vanilla 25 diagram. Hell, for all I know, I've done the same with that one in years past and have forgotten.
×
×
  • Create New...