CobraMarty
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? Maybe us a '00-'01 with COP and see if that will work on/fire the GM COP system or convert the jeep COP to Viper coil and wires.
gm atlas (LL8) engine swap? who has done it?
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CobraMarty
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Ideally, if you have '95 or older you don't have to worry about OBD2 and emissions. Just run the GM stand alone ECU to all the GM sensors and TB.
The easiest swap would be a '95 or older 2.5L or 4.0L 2WD and transplant the engine, ECU and auto trans from a 2WD Trailblazer.
The easiest swap would be a '95 or older 2.5L or 4.0L 2WD and transplant the engine, ECU and auto trans from a 2WD Trailblazer.
yossarian19
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I think it would be easiest either way (obd1, obd2 / dizzy or obd2 w/ cop) to use the GM harness & computer. No electronics to figure, just wires. Of course that makes it less interesting, too. If you ever do swap it as a long block, I'm hella curious to see how it all works.
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Actually 96 or older, not 95 or older. 97 is the first year for the CCD driven IP.
Still not sure why you would, and adapting the CPS signal is nowhere near as easy as you think it is unless you just cut the proper reluctor ring pattern into the flexplate/flywheel and mount the Jeep sensor at the right airgap distance. If you're actually building a circuit to convert the signal it is non trivial, you can't just use time delays because that only works at one specific RPM, can't do anything really simple. Especially when you consider that late model (I forget if it's 97 or 98 and later, but I know 98s do it) ECUs are smart enough to deduce which cylinder is misfiring by the slight delay between CPS reluctor ring notches, they will not be happy at all about any slight delays from your conversion circuit not being absolutely dead nuts perfect.
It'd probably be easier to use the GM ECU. The only difficulty is running a late model IP and that only matters if you want to keep it stock looking instead of ripping out the stock cluster and putting in aftermarket gauges.
Still not sure why you would, and adapting the CPS signal is nowhere near as easy as you think it is unless you just cut the proper reluctor ring pattern into the flexplate/flywheel and mount the Jeep sensor at the right airgap distance. If you're actually building a circuit to convert the signal it is non trivial, you can't just use time delays because that only works at one specific RPM, can't do anything really simple. Especially when you consider that late model (I forget if it's 97 or 98 and later, but I know 98s do it) ECUs are smart enough to deduce which cylinder is misfiring by the slight delay between CPS reluctor ring notches, they will not be happy at all about any slight delays from your conversion circuit not being absolutely dead nuts perfect.
It'd probably be easier to use the GM ECU. The only difficulty is running a late model IP and that only matters if you want to keep it stock looking instead of ripping out the stock cluster and putting in aftermarket gauges.
CobraMarty
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I thought Child9 and his '96 had problems b/c of the year, any '95 or before only has to do the sniffer test, no OBD scan test.
HESCO has some interesting CPS mods. like this-
http://www.hesco.us/shop.asp?action=showpic&id=168440&header=false
HESCO has some interesting CPS mods. like this-
http://www.hesco.us/shop.asp?action=showpic&id=168440&header=false
yossarian19
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Good call Kastein.
Now who wants to pony up on this? With the oil pan & a custom tune, it might come out cost competitive or at least close with the V8 swap & its headers / exhaust.
Course, my Jeeps are too new to be smog exempt, so it probably isn't me who figures out.
Now who wants to pony up on this? With the oil pan & a custom tune, it might come out cost competitive or at least close with the V8 swap & its headers / exhaust.
Course, my Jeeps are too new to be smog exempt, so it probably isn't me who figures out.
CobraMarty
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In his 2JZ swap thread, This is what I thought for using a '95.
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From what I've heard, that causes sporadic CELs on various late model XJs and TJs for the same reason I gave - the diameter of the harmonic balancer is so much smaller than the factory reluctor ring that it's difficult to maintain the same tolerances in the slots and thus at higher RPMs, there's enough jitter on the signal that things get out of whack and the ECU pitches a fit.
OBD1 vs OBD2 is legislative confusions - as long as the motor is newer than the chassis it goes into, and all the emissions equipment is intact (this varies from state to state and station to station as to who gives a crap) it's legal EPA wise. An OBD2 engine going into a 96 is going to be legal as long as it's done right. My concerns were entirely engineering based, a 96 is so close to a 95- on instrumentation and gauge wiring (NOT on ECU or engine wiring harnesses, though) that they might as well be the same thing. The tach signal is fed by the ECU (but is a simple pulse signal) and everything else is either an individual sender or something else easy to fake. I'd have to run the numbers again but basically the tach signal is x pulses per thousand revolutions of the crank, so you can drive it with a tap off one/two/three of the negative sides of the ignition coil(s) diode-ANDed together, then some variety of pulse rate divider circuit built out of inexpensive logic chips or a small microcontroller.
CobraMarty
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That smaller diameter balancer makes sense.
The other is, where to make the adapter actually go?
1-Between the GM Atlas engine and AW4 bellhousing and adapt the jeep flex plate to the GM crank. This way has a problem with the starter.
2-variation of above and use the Atlas starter which is up high on the driver side, the Atlas flex plate with ring gear, then bolt on the jeep flex plate to the Atlas FP, then jeep TC and AW4 trans. Run 2 flex plates. Don't know if Atlas FP will fit inside AW4 bellhousing.
3-Atlas FP, then jeep FP and jeep TC inside GM Atlas Bellhousing then adapter to AW4 trans. Then drill/mount the jeep CPS to GM bellhousing. This is sort of how IXNAYXJ did his 5.3/AW4 adaption.
4-Use the Altas engine and GM 4L60E trans and Modify the Atlas FP to give signals to jeep CPS mounted on Atlas bellhousing. Easiest for 2WD, but could also swap in TC but then have the linkage to deal with.
Need all these 'lego' pieces to play with.
The other is, where to make the adapter actually go?
1-Between the GM Atlas engine and AW4 bellhousing and adapt the jeep flex plate to the GM crank. This way has a problem with the starter.
2-variation of above and use the Atlas starter which is up high on the driver side, the Atlas flex plate with ring gear, then bolt on the jeep flex plate to the Atlas FP, then jeep TC and AW4 trans. Run 2 flex plates. Don't know if Atlas FP will fit inside AW4 bellhousing.
3-Atlas FP, then jeep FP and jeep TC inside GM Atlas Bellhousing then adapter to AW4 trans. Then drill/mount the jeep CPS to GM bellhousing. This is sort of how IXNAYXJ did his 5.3/AW4 adaption.
4-Use the Altas engine and GM 4L60E trans and Modify the Atlas FP to give signals to jeep CPS mounted on Atlas bellhousing. Easiest for 2WD, but could also swap in TC but then have the linkage to deal with.
Need all these 'lego' pieces to play with.
