Jump to content
SAU Community

Cut Out At 5500 Rpm In 5Th And About 7000 In 4Th. No Speed Sensor ?


Recommended Posts

Hey everybody just completed my rb25 box conversion in my rb25ed 32 4 door. Now my problem is at 5500rpm in fifth it feels like i hit a wall. It will not go any where past 5500, And im pretty sure its only WOT that it does it. Someone suggested speed limiter. Sounds logical BUT i dont have the cable hooked up ? The reason it doesnt make sense is it will bounce the limiter in the third but 4th hits the wall at around 7000 and 5th hits at 5500. I dont think its fuel as it has a good bosh 040 pump and here it whizzing and all other gears are fine. Now this problem has only just happened after the box. Therefore thats why im thinking maybe some sort of limiter is in place because of it. Related mods that may help find the problem are as follows

-FMIC

-Plugs were changed about 1000k ago

-Nistuned r32 ecu

-Bosch 040

-Apexi pod in a box

-3' straight through exhaust

-34 turbo at around 10 psi

Someone suggested just give the yellow wire the snip (53) and try but would prefer to know if anyone has ever had any experiences like this.

it could just be the speed cut, but i'd have thought that 5500rpm in 5th is above 180kmh. i'd say that you are just not making enough power to overcome the drag. you'll need a lot more power to get to redline in 5th gear. when i still had access to the runway at the local airport my r33 topped out at about 6500rpm.

but if you are getting a lower rev limit in 4th as well, then it's speed cut. my old 180sx hit the speed cut on the dyno at 7000rpm (500rpm below the rev limit)

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


  • Latest Posts

    • Crazy how good the aero bar looks compared to the stock one
    • Yes, but you will need to rewire all the things that are different. CAS, coils, etc. Yes, but there is no IAT. What? You can use anything you like. It just has to be hooked up so that it will work.     Or are you wanting to just plug and play without having to do any thinking/work?
    • It's been a little over a decade since I bought the S15. As I did on my socials, I'll share some of my favorite pictures from over the years further below. If you haven't realised, pretty much all the pictures in my posts are ones I've taken.  In terms of updates, I don't have pictures, but I acquired a near-perfect pair of fog lights from a friend of mine, so those got swapped in for the pair I already had. As for the JZX110, I just got it back from being fixed. A few weeks back, I was on the highway when I suddenly drove over something with very little time to react. It was probably the size of a soccer ball, but it went under the car and banged into the underside pretty loudly. I pulled over and realized the fluid leaking was fuel, and of course, it was right near my exhaust. This required replacing the fuel tank. If you happen to be in the same predicament, thankfully this car shares a fuel tank with the JZS171, IS200, and IS300, so it wasn't too painful to replace. Enjoy some pictures as mentioned above, including the carnage from the fuel tank and a bonus picture I came across which shows how ridiculously shiny the Bugels are on the 110. So many more pictures I could share of the S15 but this will do for today, enjoy. 
    • Welcome.  Was the mistake the car, or joining us? 馃槒
    • Yeap, was me and the daughter getting coffee before heading to the new joint to measure up the fridge space and taking some pics that the solar installer wanted of the switch board
  • Create New...