Jump to content
SAU Community

Rb20det running rich after injector swap

Taslim
 Share

Recommended Posts

Taslim Rookie

Taslim

Posted
Posted
Rb20det running rich after injector swap

Hi guys pretty new to this forum need help with my 1990 HCR32 Skyline. So i bought this car it had RB20DE with auto tranny i swap the gearbox to manual than replaced the motor to RB20DET using the DE harness plus the injectors. It worked fine with stock boost of 5 psi. Than i installed a bigger turbo (to4e) the car car started to ping on boost above 7 psi i changed the ecu from a rb20det very little difference was made so i went on to change the injectors to 550cc (mostplus brand) now the car runs so rich and worse than before where it used to run with rb20de injectors. Can someone guide me on the next steps so that i can get to go up till 10 or 11 psi of boost and dolve the over fueling issue . Also the why is the idle so rough. The spark plugs are so covered with carbon deposits i guess thats due to running rich. Any suggestions??

hardsteppa Grand Master

hardsteppa

Posted
Posted

so i'll just clarify

" The spark plugs are so covered with carbon deposits i guess thats due to running rich. Any suggestions?? "

you've put bigger injectors in, haven't done anything to adjust the tune, and now it's running rich?

as Trex said...probably wheel bearing, or Johnson rod.

KiwiRS4T Grand Master

KiwiRS4T

Posted
Posted

Your car will never run properly as the ecu you are using is not tunable. You need either an aftermarket ecu or at least a Nistune chip. If you are feeling lucky you may find Nistune or someone else will put a tune on the chip that roughly matches your set-up although i think you will need at least a Z32 afm. I assume you have fitted an intercooler of some sort? Does someone like Max Sols in Suva have a dyno?

  • Like 1
89CAL Grand Master

89CAL

Posted
Posted

O.K
I will explain this

We are going to use some random injector values to make it easy

If your stock injectors are 250cc and at 3000rpm they are injecting at 50% of their maximum - 125cc injected
If you then put 500cc injectors in and dont change the tune to tell the ECU that there are bigger injectors in, guess what happens - 3000rpm you get 50% of the maximum - 250cc injected

It needs a tune

It needs alot of things by the sound of it

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
 Share
Go to topic listing


  • Similar Content

  • Latest Posts

    • foney
      Cheap Gtr For Sale

      By foney · Posted

      BRUH, one of the biggest mistakes of my life..... and i've had plenty ;[)
    • Kapr
      "Cheap" bolt on turbo on RB25DET NEO

      By Kapr · Posted

      @Murray_Calavera iam just considering options 🙂 of course it is very expensive so that why i ask here 🙂  @joshuaho96 I looked at that GCG hybrid(i remember looking at it few weeks before) So this is "that" hybrid where i send them my turbo and they upgrade the inside to Garrett stuff and then they send it back. It cost around 1200-1300 USD which is FAR cheaper than the HKS and it is what iam looking for(i just do not have experience like this...to send something off to "upgrade" ) @tylink720 that is like 150 USD turbo no? 😄 I dont think i have the "ease on my mind" with this kind of turbo. I just put over 7000k USD to "LINK" up my engine...dont want to blow it up with cheap turbo 😄     EDIT: https://www.cj-motor.com/gcg-turbo-charger-for-nissan-rb20det-rb25det-high?srsltid=AfmBOooVeOZ6CZ6r1AIv5m-KPaa6BvudIPJTY8LW78khkd-gQlsaCht9 I looked at this and it seems ok? It is that CGC hybrid and it costs around 1250 USD (with back shipping). Do any of you have experience with this hybrid on NEO turbo? I quickly look thru the forum/web and it seems very good.
    • Rezz
      First time Skyline owner

      By Rezz · Posted

      Echo the awesome sentiment 👍 Definitely a car worth saving. Looking forward to seeing updates as well. 
    • Matt Z
      SAU NSW - Chickos Cruise

      By Matt Z · Posted

      Scenic roads, stunning skylines, and Chickos to finish it off! Join SAU NSW as we cruise through the Royal National Park and along Lawrence Hargrave Drive to Figtree! Sunday 26th October 2025 4:30PM Meeting Waterfall Station Parking 5:00PM Cruise Departure Royal National Park > Lawrence Hargrave Dr > Memorial Dr > Sid Parrish Park 6:15PM Arrival at Sid Parrish Park Figtree Meet Location: Waterfall Station Parking Final Destination: Sid Parrish Park RSVP: https://forms.gle/E4s5SiRKQfDdypky8 *Disclaimer* There will be a lead and follow car so no one should get lost. If you would like to attend or bring others along please put your name down and a +1 as numbers will be needed prior! This is NOT a race and we will all be adhering to all road rules. If this is what you want please come to one of our many track days. This is an official SAU:NSW event and will be run under a CAMS permit. One of the things that really sets our club apart is our commitment to being true enthusiasts. When on normal roads we strive to maintain good relations with the authorities as well as the public in general. When attending one of Skylines Australia NSW events please try to: • Be aware of surrounding environment and act accordingly. • Drive courteously on the state’s roads as a true enthusiast should. • Understand how important it is to maintain the good name of SAU NSW and thus, treat others accordingly. • Any misbehavior will not be tolerated and you will be asked to leave.
    • MBS206
      "Cheap" bolt on turbo on RB25DET NEO

      By MBS206 · Posted

      It's funny, as Ive seen plenty of people use them in cheap builds on YT. And they actually go okay, even though a lot of other maxspeedingrods stuff is terrible. Those turbos seem reliable enough, the only part being, a good quality turbo that is "identical" to it, will out perform it day in and day out. In both a lower boost threshold, and the ability to flow more air at the same boost pressure. As a cheap cheap replacement, not a terrible choice. For cheap and shouldn't blow in a day, not terrible (like other eBay/Temu turbos) for low cost and still decent performance, that's where the question comes in to play from the results I've seen. I'd actually find it hilarious to buy one, and strap it to a paddock basher or some other cheap as POS originally NA car, and send it to the moon!
×
×
  • Create New...