Jump to content
SAU Community

What Size To Get?

CAT_SPEW

By CAT_SPEW,
in Engines & Forced Induction

 Share

Recommended Posts

CAT_SPEW Rising Star

CAT_SPEW

Posted
Posted

I am wanting to upgrade my injectors on my RB25 but don't know if 740cc's will be too big..

It's currently making around 250rwkw on about 12.5psi and I'm pretty sure they are maxing out about now.

Will 740cc's be a problem if I have the car dyno tuned after installing them??

I'm looking at making more power later on so I don't want to go too small..

Link to comment
https://www.sau.com.au/forums/topic/84902-what-size-to-get/
Share on other sites
CAT_SPEW Rising Star

CAT_SPEW

Posted
  • Author
Posted
I was running 550cc and getting 330 rwkw

What % duty cycle were they running at??

Did the car run fine after you installed them, or was it running too rich??

I need to know if I will be able to drive it to the dyno shop after installing them or if it will cause damage..

Link to comment
https://www.sau.com.au/forums/topic/84902-what-size-to-get/#findComment-1537282
Share on other sites
blind_elk Grand Master

blind_elk

Posted
Posted

Do you have an aftermarket ECU?

As a cheaper option, why not try installing a Malpassi, or similar, rising rate FPR, and increase the base (idle) pressure. Installing huge injectors will cause the car to idle too rich.

Link to comment
https://www.sau.com.au/forums/topic/84902-what-size-to-get/#findComment-1537335
Share on other sites
CAT_SPEW Rising Star

CAT_SPEW

Posted
  • Author
Posted

I had a search on google and found some info from Meggala's site on injectors.

Heres the link.

LINK

Going from the 550CC's should be able to support at least 500hp if I worked it out right??

Still don't know if they will screw the engine while I'm driving to the shop to get the tune but..?

Link to comment
https://www.sau.com.au/forums/topic/84902-what-size-to-get/#findComment-1537360
Share on other sites
R31Nismoid Grand Master

R31Nismoid

Posted
Posted

I was using nismo 740's... i'd reccomend to get those. There were great for me. No issues.

direct fit to the stock rail... (unlike sard)

kept stock reg also (no need for a bigger one)

Using a PowerFC it'll be 100% fine. You'd never notice injectors that big were in there

Link to comment
https://www.sau.com.au/forums/topic/84902-what-size-to-get/#findComment-1537741
Share on other sites

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

    • 33GTRV
      Rb26 iron block limit

      By 33GTRV · Posted

      Here is a recipe. Sonic blocks till you get one that has a good enough bore. Get a torque plate and block brace, use your choice of fasteners (arp ect) bolt the thing together empty, half fill it and let it cure. Release it when it has, go to a REPUTABLE RB Builder and get the thing line bored/honed and cylinder honed to size, then wash. Once its all clean and dandy, wash and blow it out again. Then again.  Assemble said engine to your desired clearances with oil control mods, gasket to suit desired CR/Squish ect. Attach your extended sump with proper trap door oil baffles and head drain plumbed to sump with a SUMP BREATHER SYSTEM. Build your front diff with a decent LSD, rebuild your transfer case with a few extra plates, more than likely replace your tailshaft centre bearing and tighten up the rear diff. Tune to minimise excessive midrange cylinder pressure (timing unless you like to split bores and rebuild engines) Enjoy your engine, but hate the fact you are now destroying engine mounts, gearboxes, gearbox mounts, diff output flanges and driveshafts, diff mounts, tailshafts and front CV's.   Disclaimer.... Ive never done any of the aforementioned stuff.......
    • GTSBoy
      R32 GTS (RB20DE) Injectors Replacement

      By GTSBoy · Posted

      440s will support well over 400HP on petrol, which is a decent place to be for an RB20. 230+rwkW. Will be a safer bet for idle/low load. 550s would be nice for the extra headroom. I've made the same decision with mine (Neo25). 1000s are probably too big for the Nistuned ECU, so I have some smaller ones.
    • GTSBoy
      RB25DET Series 1 & Series 2 Gearbox Identification

      By GTSBoy · Posted

      thumbsup
    • AdiR34
      Did tie rods. Steering now not "springing" back.

      By AdiR34 · Posted

      Appreciate everything guys. I did go ahead and get an alignment... most of my complains are solved. Car is not perfect, but it's good enough. If I notice uneven tire wear or anything I'll just take everything back to stock.  Thanks again!
    • GabsReDeal
      R32 GTS (RB20DE) Injectors Replacement

      By GabsReDeal · Posted

      They still have not shipped the 550cc injectors as they weren't in stock, so in theory I could ask to get the 440cc ones instead, if those work better in my scenario. They're the same price so really shouldn't be an issue. Unfortunately I am not so knowledgeable in most parts of tuning so I wasn't sure what's best to choose between the two. 440cc ones are the lowest they have (not in stock, but available to buy nonetheless).
×
×
  • Create New...