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420A 7100 rpms

Posted by Jonnychance, May 15, 2019

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  1. Jonnychance

    Jonnychance Probationary Member

    Joined Jul 2, 2017
    Cashmere, Washington
    I barely went over the rev limiter to abt 7100-7200 is my okay it's just drives perfectly fine
  2. o0GuitarKid0o

    o0GuitarKid0o Proven Member

    Joined Dec 12, 2013
    Winnipeg ,MB, MB, Canada
    If its stock keep it below the rev limit but if you have aftermarket valve springs and built motor to handle more rpm than giver .

    The Thing you gott be careful with is valve float
    Research it

    Street Build 566  7

    1991 Plymouth Laser RS Turbo
    fwd · automatic · 1G DSM
    1990TSIAWDTALON likes this.
  3. BLACK'98DSM

    BLACK'98DSM Proven Member

    Joined Feb 9, 2019
    Hoover, Alabama
    Don't worry if it drives fine but never ever do that again.
    Unless you want broken stuff

    Street Build 1K  11

    1998 Mitsubishi Eclipse N/T
    fwd · manual · 2G DSM

    235  2

    2012 Murray Explorer Dune
    rwd · automatic · Misc Vehicles

    149  6

    2009 Troy Bilt Bronco
    rwd · automatic · Misc Vehicles
    1990TSIAWDTALON likes this.
  4. rabenne

    rabenne Proven Member

    Joined Apr 21, 2006
    Kenosha, Wisconsin
    You hit the limiter? Or went over it?

    Street Build 6K  15

    1995 Eagle Talon TSi
    awd · manual · 2G DSM
  5. tk106

    tk106 Supporting Member

    Joined Sep 11, 2017
    Cincinnati, Ohio
    You have 24 hours of driving left before she blows up. It's now a ticking time bomb. j/k ROFL

    88  3

    2000 Jeep Cherokee Sport - Classic
    awd · automatic · Misc Vehicles

    116  4

    93 Civic 4 Door -sold-
    fwd · manual · Misc Vehicles

    Street Build 2K  6

    1992 Eagle Talon TSi AWD
    12.625 @ 111.42 · 1G DSM
    1990TSIAWDTALON likes this.
  6. curt-s

    curt-s Proven Member

    Joined Dec 21, 2008
    Winterville, MB, Canada
    It is hard to answer that question because, while a new motor could do 7000rpm (provided it was capable of that), the same motor 10 years later might let go. too many variables, parts, age..
    hell even the exact same two parts new can vary -- one handles something, the other not so much.

    generally, if you have revved too high, it does not take too long to show itself. but, at the same time, perhaps the high oil pressure induced by the high rpm dislodged something which is now reducing flow to a bearing surface.. and that ticking time bomb analogy becomes more friction than fiction (teehee).

    only time will tell. keep an ear out for strange noises.

    Street Build 2K  1

    1991 Eagle Talon TSi
    fwd · manual · 1G DSM
  7. Canadian_CD9A

    Canadian_CD9A Proven Member

    Joined Feb 10, 2012
    Winnipeg, MB, Canada
    I bounce my engine off the 7500 RPM limiter all the time in autocross, so I highly doubt any damage was done; the limit would be lower if there was a risk at that RPM. Stock valve train (with stock cams) will go 8,000 or more, but the connecting rod bolts probably aren't safe past 8,000.
    Mello likes this.
  8. Jonnychance

    Jonnychance Probationary Member

    Joined Jul 2, 2017
    Cashmere, Washington
    Okay thanks guys yeah I drive the completely stock 420a motor and it sees 5000 to 6000 rpms daily shld I install new valve components or other parts?
  9. ThunderChild

    ThunderChild Supporting VIP

    Joined Jan 5, 2012
    Rathdrum, Idaho
    My vote is keep it stock and don't thrash it too hard unless you want to rebuild/fully build sooner or have a second car.

    420a's in stock form are nice little driver's if maintained well and not wrung for everything they're worth, but past that you start noticing shortcomings relatively quick.

    Street Build 166  3

    1990 Plymouth Laser N/T
    fwd · manual · 1G DSM

    266  8

    1987 Toyota Pickup/Hilux
    awd · manual · Misc Vehicles

    Street Build 793  7

    1997 Mitsubishi Eclipse Spyder GST
    fwd · manual · 2G DSM

    Street Build 1K  1

    1992 Eagle Talon TSi AWD
    manual · 1G DSM

    Street Build 2K  10

    1992 Eagle Talon TSi AWD
    awd · manual · 1G DSM
  10. Canadian_CD9A

    Canadian_CD9A Proven Member

    Joined Feb 10, 2012
    Winnipeg, MB, Canada
    Oh, 420A. Don't do reliability mods, it's cheaper to just throw a junkyard engine in if yours blows up.

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