The 3.7 is a reliable engine - it is powerful and fuel efficient for it's size because the 2v\cyl heads breathe excellently, also making the engine a perfect candidate for turbo-charging - don't believe it? - millions have been sold in single and dual-turbo versions: check out all the turbocharged\waste-gated V6 engines in 2-door and 4-door coupes and sedans from the Mitsubishi (and Chrysler) stables - your 3.7L V6 is just an up-sized Mitsu 3-liter V6 - the recent Mitsu Montero V6 was at some displacement near 3.7L, iirc, tho not turbocharged
- the ECM will handle positive manifold pressures based on feedback from the Manifold Air Pressure sensor, also referred to as the Boost sensor - the upgrading parts are out there in local boneyards, and all that may be required is an upgraded ECM program that works with pressure above Baro, rather than below - vacuum, all important to a gasser (patooie!) engine, is just any pressure level that is less than Barometric, or atmospheric, pressure
- stock feedback from the O2 sensors and knock sensor should pull fuel before extensive damage can occur from extreme fuel\air ratio lean-out, and a relay could be added to the warning indicator on the instrument panel to control the wastegate as further protection
- you would also need to deal with EGR, as the valve is expecting vacuum in the intake, as well as specific exhaust gas pressures which will increase drastically when adding the t\c
- you would also need a charge-air cooler, which DCJ thoughtfully provided in the KJ CRD, an exact fit to those less-fortunate KJ versions using that other fuel
- your 3sp\od trans is just a kiddie-sized version of the 48RE used behind the Cummins, and a junior-sized version of the 46RE used behind the 318 Magnum engines in the Dakota\Dacoma\Ram 1500 trucks, so upgrades from the DCJ stables are likely possible, not to mention the aftermarket segment such as Transgo and Suncoast
- the manual transmission may require the clutch\pressure plate from the V8 version to manage the extra power, also the aftermarket segment should have some upgrades
- check it out, should be no hill for a stepper - that's my story and I'm stickin' to it................
Note - the 4-cyl and some Mitsubishi V6's have 4 valves per cylinder - this version has only two per, derived from the base V6 in all platforms - turbocharging applies to the 4 ****** as well as the bent 6
The concept is sound, whether 2v or 4v per cylinder - your engine is an air pump - there are three ways to increase airflow\volume (and fuel rate ) in any air pump\engine in order to increase it's output:
- increase displacement: bore and stroke
- increase rpm: camshaft, valves
- increase applied pressure: turbocharger or supercharger
The last method involves little additional engine modification as the original cam timing, crank (stroke) and pistons (bore) work well with increased pressure to 15psig, even more if the engine is of modern design - if the engine is 140hp at one atmosphere (Bar) 14.7psia, then power can be nearly doubled at two atmospheres (2 Bar) 30psia, or 15psig Boost, as the engine is now pumping twice the volume to which can be added twice the fuel - more air\fuel = more btu = more power - the turbo is essentially free power, operating off the normally wasted btu in exhaust gasses - a supercharger requires parasitic drain from the crankshaft: takes bunches of horsepower to drive that auxiliary air pump
The turbocharger is the easiest route to power, and your engine, at various stages in it's past, was factory-equipped with one or two turbochargers - find the stuff and adapt it - easy enuff, compared to similar upgrades on other engines - try it, you'll like it...............
- the ECM will handle positive manifold pressures based on feedback from the Manifold Air Pressure sensor, also referred to as the Boost sensor - the upgrading parts are out there in local boneyards, and all that may be required is an upgraded ECM program that works with pressure above Baro, rather than below - vacuum, all important to a gasser (patooie!) engine, is just any pressure level that is less than Barometric, or atmospheric, pressure
- stock feedback from the O2 sensors and knock sensor should pull fuel before extensive damage can occur from extreme fuel\air ratio lean-out, and a relay could be added to the warning indicator on the instrument panel to control the wastegate as further protection
- you would also need to deal with EGR, as the valve is expecting vacuum in the intake, as well as specific exhaust gas pressures which will increase drastically when adding the t\c
- you would also need a charge-air cooler, which DCJ thoughtfully provided in the KJ CRD, an exact fit to those less-fortunate KJ versions using that other fuel
- your 3sp\od trans is just a kiddie-sized version of the 48RE used behind the Cummins, and a junior-sized version of the 46RE used behind the 318 Magnum engines in the Dakota\Dacoma\Ram 1500 trucks, so upgrades from the DCJ stables are likely possible, not to mention the aftermarket segment such as Transgo and Suncoast
- the manual transmission may require the clutch\pressure plate from the V8 version to manage the extra power, also the aftermarket segment should have some upgrades
- check it out, should be no hill for a stepper - that's my story and I'm stickin' to it................
Note - the 4-cyl and some Mitsubishi V6's have 4 valves per cylinder - this version has only two per, derived from the base V6 in all platforms - turbocharging applies to the 4 ****** as well as the bent 6
The concept is sound, whether 2v or 4v per cylinder - your engine is an air pump - there are three ways to increase airflow\volume (and fuel rate ) in any air pump\engine in order to increase it's output:
- increase displacement: bore and stroke
- increase rpm: camshaft, valves
- increase applied pressure: turbocharger or supercharger
The last method involves little additional engine modification as the original cam timing, crank (stroke) and pistons (bore) work well with increased pressure to 15psig, even more if the engine is of modern design - if the engine is 140hp at one atmosphere (Bar) 14.7psia, then power can be nearly doubled at two atmospheres (2 Bar) 30psia, or 15psig Boost, as the engine is now pumping twice the volume to which can be added twice the fuel - more air\fuel = more btu = more power - the turbo is essentially free power, operating off the normally wasted btu in exhaust gasses - a supercharger requires parasitic drain from the crankshaft: takes bunches of horsepower to drive that auxiliary air pump
The turbocharger is the easiest route to power, and your engine, at various stages in it's past, was factory-equipped with one or two turbochargers - find the stuff and adapt it - easy enuff, compared to similar upgrades on other engines - try it, you'll like it...............
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