1.5T Power Metrics & Limitations for 1.5L Turbo (Non Si models)

  1. OP
    Hollywoo0220

    Hollywoo0220 Customer Service oriented (most of the time) :-)

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    You do understand (if you read the metrics) that the stock set-up is already tapered. You aren’t making the power to surpass the stock exhaust system w/o an upgraded turbo.
     
  2. Myx

    Myx Senior Member

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    I understand your thinking. I tried this philosophy on my 2015 Honda Fit. Even made a thread about it ~~~> Myxal Reducing Exhaust Diameter And another thread, longer, at FitFreak ~~~> Myxal Reducing Diameter Exhaust (Fitfreak)

    In the meantime, since I have a PRL down pipe attached to the stock front pipe and stock exhaust (That are both tapered from the factory), I guess just changing out the downpipe would fit this thinking in a sense, right? :headbang::)
     
  3. Hondanickx

    Hondanickx Senior Member

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    I don't know what size the PRL downpipe is on the exit ,but they start at 3" afaik. I know Wagner tuning also makes the downpipe for the fk2 type-r (which is the same engine as the FK8) and they start at 4" and exit in 3" .They also use the highly reputable HJS catalytic converters which are designed this way . (Any properly designed cat converter has a wide(r) entry taper and a shallow(er) exit taper)
     
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    Hollywoo0220

    Hollywoo0220 Customer Service oriented (most of the time) :-)

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    It is the Exhaust Turbine of the stock turbos gents that is the restriction. Once the turbo is upgraded the flow stream (at that point) can be improved.
    Higher octane fuel and a proper tune can achieve that on the stock system. An intercooler is beneficial when consistency is desired.
     
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    Hollywoo0220

    Hollywoo0220 Customer Service oriented (most of the time) :-)

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    @charleswrivers
    Yes, I agree with you wholeheartedly. The Gen11 will have an increased Volumetric Efficiency and more than likely remain at the same power levels - thus increase fuel economy.
    As I understand, Mazda’s SkyActiveX (when released later this Fall’19) is a high compression combustion ignition and will have an incredible VE. Basically a supercharged system with responsiveness, power production, and fuel economy.
     
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  6. Myx

    Myx Senior Member

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    #21 Myx, Jun 2, 2019
    Last edited: Jun 2, 2019

    Understood! With this in mind, I'll be keeping the stock turbo. Already using higher octane, a tune (Base) and upgraded intercooler. Getting fairly close to what people are saying the torque limits are with the CVT (240ft-lbs or thereabouts). No point getting a bigger to go past this point.
     
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    Hollywoo0220

    Hollywoo0220 Customer Service oriented (most of the time) :-)

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    Well...
    If you are yet using one of the BASE tunes (probably the 21psi)? You are not nearing the high-end limitation of the CVT; nor @/or near 240lb/ft. You will need to custom tune for that and require a percentage of E85. The only way to keep the torque curve at a higher RPM is to upgrade the turbo (to prolong the CVT). Me personally, I wouldn't venture into that realm.
    With your DP, you are probably feeling a tad (400RPM) slower in the lower RPM, until your exhaust pressure builds for torque - but, running a bit smoother in the Mid all the way to 5600rpm. The Intercooler is truly the way to go to recover from heat soak faster. :)
     
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  8. Myx

    Myx Senior Member

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    I only based this off my recent trap speeds and using online 1/4 mile calculators. Like THIS or THIS ONE. These probably aren't entirely accurate but they are guides. Either way, it's all good info. I appreciate your knowledge and input on this subject matter.
     
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