High comp + boost whats your take/experience

Discussion in 'Forced Induction' started by that_civic, Nov 30, 2017.

  1. that_civic

    that_civic Well-Known Member

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    I'm umming and ahhing about what to do with my k24 since its stripped back, part of me wants the n/a and part of me wants the boost. I was thinking running it n/a for a bit then boosting it but it will always have forged rods and high comp pistons 12/5/1 mahle pistons. I am lead to believe with higher compression it will spool much quicker which is what I want being a daily driver, so lower pressure and probably a smaller turbo since I only want around 400 so it's driveable. If it will be reliable I might just boost it as ITBS are pretty expensive.

    Your thoughts ...
     
  2. jesse888

    jesse888 Ek9+Turbo+Nurburgring= Heaven Staff Member Donator

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    youll not do very well boosted at 12.5-1Cr boost pressure will be severely limited.
    id not believe that higher Cr dramatically reduces spool time either tbh.

    unfortunately if you try to build a single engine that can do both youll just end up with a compromised engine no matter what decision you make.
     
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  3. that_civic

    that_civic Well-Known Member

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    So I'm better off going with lower comp pistons and a turbo that's designed for quicker spooling?
     
  4. jesse888

    jesse888 Ek9+Turbo+Nurburgring= Heaven Staff Member Donator

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    you need to be careful with going for a small turbo, they tend to choke out abit at high rpm.
    remember you have 2.4Litres and the ivtec system can be used to spool a turbo faster than a conventional engine would.
    lower comp is more ideal yes.
    will it be a frank build or just straight k24?
     
  5. jesse888

    jesse888 Ek9+Turbo+Nurburgring= Heaven Staff Member Donator

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    you can use valve overlap to pull the dynamic conpression down but that will cause other issues so its much easier to just pull the static Cr down to like 10-1ish.

    id probably go with something like a gtx3071 on a k24 if you wanted response. mine is pretty decent on a b18 and will easily outrun your power goals.
    i have 1.7bar by about 4500rpm, remembering its a 1.8L without the Ivtec.
     
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  6. that_civic

    that_civic Well-Known Member

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    Thanks for the info, yes It will be a frank swap. I'd assume cam choice will also be a factor for spooling times too? I want as little lag as possible basically, want it to be somewhat responsive like n/a but obviously more power and good reliability.
    Got the bare block atm so pre planning what I will need.
     
  7. jesse888

    jesse888 Ek9+Turbo+Nurburgring= Heaven Staff Member Donator

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    id use the standard k20a2 cams.
    supercharger not an option?
     
  8. that_civic

    that_civic Well-Known Member

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    I was thinking rotrex at one point so that could be an option.

    What's a boosted Honda like in regards to response, is there much lag? I think I might just go for around 10ish on the compression ratio as thats close to stock and seen plenty of setups similar to that over on k20a.org.
     
  9. jesse888

    jesse888 Ek9+Turbo+Nurburgring= Heaven Staff Member Donator

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    depends on what you call lag really.
    if you mean boost threshold then mines on full song alittle after 4k but its pulling long before then.
    as far as throttle response goes i think mines pretty decent for its size, the smaller turbo i has before was defo more punchy but its hardly noticable for the extra grunt i get from it
     
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