Max bhp for a unforged 1jz

Thread in 'Technical Questions' started by Mattvaughan180, Feb 16, 2019.

  1. Mattvaughan180

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    Hi all recently bought a Toyota chaser(on its way back to the uk shortly from Japan)

    It’s a 2000 chaser so the vvti lump, my question to you guys is how much bhp can you get out of a unforged 1jz?
    I previously had a s14 which I changed out the turbo, injectors,clutch etc you get the idea and was sitting just shy of 350bhp with 380bhp being the point where you want to change the cams/head gasket etc and I intend to eventually change the turbo/injectors etc etc on the chaser is 500bhp a achievable figure or am I pissing in the wind??
     
  2. Japtorque

    Japtorque Member

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    100bhp per cylinder isn't too much for a 1j ,
    turbo, injectors, fuel pump, clutch , ECU.
     
  3. Mattvaughan180

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    Brilliant news plenty of potential as long as your pockets are deep
     
  4. Japtorque

    Japtorque Member

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    is yours completely standard? or do you have the basics such as,
    Exhaust
    front mount intercooler
    boost controller
    coilovers ,
     
  5. Mattvaughan180

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    It’s on the ferry from Japan at the mo but it’s got intercooler, muffler coilovers, body kit and wheels and that’s about it

    Bits I am fitting are full 3 inch exhaust from turbo elbow, boost controller, bigger fuel pump, j pipe delete,
     
  6. orange_beastie

    orange_beastie Pickup driftin

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    I think 500bhp on a standard engine is about as much as you want to go, an rb25 can do just over 500bhp at the crank before you start getting problems so a 1jz id recon about the same mabe a tad more as the bottom ends we’re stronger.
     
  7. Mattvaughan180

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    500hp is more than enough for me. My plan in the long run and this won’t happen this year but I will collect bits over winter and do next spring are:
    Uprated clutch and flywheel
    Bigger injectors
    Apexi power fc
    Top mount manifold
    Uprated turbo(any suggestions people??)
    Dyno time
    Would this get near the 500hp figure?? Or would I need cams/springs also
     
  8. orange_beastie

    orange_beastie Pickup driftin

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    On a 1jz theres loads of tuning on here id just try a front mount good 3” exhaust, and decent air filter,a apexi fc and turn up the boost till the injectors are at 85/90% duty and ur still getting a good afr reading then see how it goes.
    I know its a no nonsense approach but many people have done the most basic mods and get good power for years, others have spent a fortune and only last a few months, its all in the tuning of ur engine/map that makes it a reliable car not how many fancy bits you can bolt on.
    But seriously do ur research first before buying stuff. And then you only have to buy once.
     
    • Informative Informative x 1
  9. LUX1

    LUX1 Member

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    Im in a similar position to you. Chaser is on the boat coming over and hopefully landing next month. Im planning go go 555cc injections (EV14s) with a hybrid CT15b turbo. Car has front mount, filter and exhaust but I'll fab a decat pipe up for it. Just picked up an Apexi FC for a reasonable price aswell.

    Looking for 400ish max as my silvia had 334bhp. Even thats probably excessive though. but hey why not
     
  10. orange_beastie

    orange_beastie Pickup driftin

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    Should easily see 400hp with those mods.
     
  11. orange_beastie

    orange_beastie Pickup driftin

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    I have a standard rb25det standard injectors
    With topmount and super t70 turbo with external wastegate set at 1bar, 3” exhaust
    Front mount, 300lph fuel pump and a map2ecu piggy back ecu.
    When i last done a rolling road many years ago it done 390bhp at the wheels at ultimate streetcar santapod.
    That was with a dodgy lamber sensor making my car overfuel like hell. The tuner there said with new sensor and fueling correctly should be 420bhp easily. It was mental to drive in anything but dry conditions.
     
  12. Japtorque

    Japtorque Member

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    I'll stick my neck out and say 320-360bhp maxxed out on the CT15 turbo at 18-21psi boost ..
     
  13. Mattvaughan180

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    I sold the s14 because I wanted more power 350bhp was good but I wanted more and a six cyclinder car,400bhp will seem slower than your Silvia don’t forget a chaser is 200kg heavier(30 stone) that’s hauling some ass, I will do the basic mods this year see where I go long term,get deatschwerks injectors there pretty tasty.
     
  14. orange_beastie

    orange_beastie Pickup driftin

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    The ct15 turbo is good for 450bhp on a 1jz
    Driftworks sell them.
     
  15. Japtorque

    Japtorque Member

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    well I never knew that ! do you mean a hybrid ?
     
  16. orange_beastie

    orange_beastie Pickup driftin

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  17. Mattvaughan180

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    Just send it to midlands turbo and there do the same,a guy on here I was talking to recommend that
     
  18. Japtorque

    Japtorque Member

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    that does sound about right , my HKS gt2 makes 336 at the hubs at 1bar boost. it is sort of a hybrid , stock location and lines downpipe.
    although I wouldnt suggest the HKS cos its fairly expensive, I was lucky my car came with it from japan.

    might turn it up soon and see what its got :smokin:
     
  19. Donce

    Donce New Member

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    Hi very interested in your car power with hybrid turbo
     
  20. Mattvaughan180

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    Just a bit of a update, car at present as it stands mods wise:
    has a hpi j pipe delete(well worth doing)
    Aem 340ltr fuel pump, custom made turbo elbow and down pipe/3 inch exhaust all the way through to Blitz Nurspec backbox, hpi front mount, was going to fit a boost controller but when setting up on the Dyno it was making just under a bar of boost so maxed out, made 331bhp,
    I’m pretty happy as it sits the only thing is now if I want more power it’s going to cost thousands
     

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