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  1. 4BTA CUmmins MArine

    Performance Discussion
    I have 2ea cummins marine 4BTA 3.9 they dont go over 1800RPM neither of them . WHat can i do. I already replace the diesel filters, Oil filters, air filters, diesel lines, turbos seems working properly. I dont think its an injection problem because isnt smoking at all. ANyone that coul help it...
  2. Cruising RPM for the 4bt? TC Stall Speed

    Transmission, Adapter, Transfercase Discussion
    I'm trying to figure out tire size, gear ratio and cruising RPM. Corral.net calculates my hwy speed for stock 255-70R16 tires in OD to be:Engine RPM: 1800 Vehicle Speed: 75.5607956090749 Read End Gear: 3:73...
  3. Lost the original Starwheel / Fuel pin position! How do i find it?

    Performance Discussion
    A few months ago i decided to finally turn up the ve pump, i turned the starwheel, fuel pin, and adjusted the timing. i also had the 3200rpm gov spring put in soon after. it was all going fine and the spring changed my top speed to 80mph (its in a jeep so thats fast enough for me!) i was...
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