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  1. #1
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    Dave Bryant
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    Default LT4 knock module

    I have a 1995 LT1 engine that will be completely rebuilt and I plan to use an LT4 knock module in place of the stock unit. Is this a "plug-n-play" swap or does something also need to be done in tuning?

    Thanks

    Dave

  2. #2
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    Plug-and-play. Unless you're going with full roller rockers, it may not be worth the inflated cost.
    SOLD - GONE TO A (VERY) GOOD HOME ! - 94 Formula A3+1: 381ci forged stroker - Callies Stealth, Oliver 5.85 billet rods, BME nitrous pistons / CNC LT4 heads / CC solid roller / TH400+GearVendors OD / 4.11 Strange 12-bolt / 300-shot N2O / Spohn Suspension / roll bar / MoTeC M48 Pro engine management system /a few other odds 'n ends.

  3. #3
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    Yes, I'm going to use full roller rockers and you are right about the exorbitant cost!

    Dave

  4. #4
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    i actually had a lt4 knock module fail on me once. it was weird. ended up using a stock lt1 module and got the tune right and it was good to go

    Sent from my SM-N975U using Tapatalk
    2021 Charger Scat 392
    1994 Firebird Formula 381 stroker - Carrying the torch! - 9.90 @ 134.3mph on a 200 shot

    The wrench/driver for LTConvert's 94 Z28- Ellwein 383/LE Trickflows/ D1SC / CPT Ultra Pro Race 4L60E
    10.78 @ 125mph. Shooting for 9.99 for Frank Cahall!

  5. #5
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    Default

    I've heard that the extra noise from roller rockers could be tuned out, but my thought is that if you raise the threshold of the LT1 mod so that it ignores the rockers, wouldn't it maybe miss some of the ping if that was there? But then, maybe that's all the LT4 mod does anyway. I plan to send my PCM out for a tune, the donor car was wrecked in about 1996 and had sat somewhere until a couple of years ago when the PO thought he would do what I am doing. I have no idea what shape the PCM is in.

    Dave

  6. #6
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    The knock module is a noise “filter”. For the LT4 it removes the specific noise signature of the roller rockers, plus whatever else it was filtering from the LT1. Interesting info - 1993 F-Body LT1 did not use a removable knock module.
    Last edited by Injuneer; 04-29-2020 at 09:11 AM.

  7. The Following User Says Thank You to Injuneer For This Post:


  8. #7
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    So the signatures of roller rockers and pre-ignition are different enough that an LT1 module could be tuned to ignore the rockers also and still retard the spark by identifying ping?

    Thanks for previous post, I appreciate it.

    Dave

  9. #8
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    I'm not aware of any way to “tune” a knock module. The tuning is in the circuitry.

  10. #9
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    Quote Originally Posted by daveb View Post
    So the signatures of roller rockers and pre-ignition are different enough that an LT1 module could be tuned to ignore the rockers also and still retard the spark by identifying ping?

    Thanks for previous post, I appreciate it.

    Dave
    You can only "tune" it down by changing how much spark retard it pulls when it senses a knock event. Stock is 10 degrees, i usually set it for 3 degrees at certain rpm or map values to only really retard timing if it senses knock WOT.
    2021 Charger Scat 392
    1994 Firebird Formula 381 stroker - Carrying the torch! - 9.90 @ 134.3mph on a 200 shot

    The wrench/driver for LTConvert's 94 Z28- Ellwein 383/LE Trickflows/ D1SC / CPT Ultra Pro Race 4L60E
    10.78 @ 125mph. Shooting for 9.99 for Frank Cahall!

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