HowlerMonkey

This thread just gave me a nightmare flashback to synchronizing the honda CBX1000 carbs. I really thought I was over that but....

I'm not sure the jeep ecu needs any tuning. My co-worker put a kenne bell supercharger kit with much larger injectors on his year 2000 cherokee and nothing else. It ran pig rich for a few drive cycles and cleaned right up with his LM-1 showing normal mixture while driving.......Hmmmmmmm.

True......maybe the consult port yields enough information to.make the hassle of setrting up an OBDII ecu more hassle than it's worth. I'll still check out the late nissan single cam units and possibly explore the GM units mentioned above.....or maybe even the jeep OBDII units for the 4.0 liter. I will definately report any findings either positive or negative since it seems you guys here at hybridz are on the sharper end of the knowledge/motivation end of the spectrum. Now it's off to the junkyard to check some stuff out.

It's possible the ecu checks whether any fueling changes made to a certain bank is actually affecting said bank. Having the sensors of both banks together in mergred exhaust on an engine the ecu divides into multiple banks could possibly "dilute" the changes the ecu expects when making an adjustment and you could run into the ecu "hunting" the proper adjustment or just throwing a light and possibly falling back on an algorithm that is not performance friendly. If one could get over the hurdles of running an ecu that expects variable valve timing, the 2jz OBDII ecu might be the ticket if you made sure your exhaust hardware coincided with the logical bank. Wait a minute......did toyota make a non vvti OBDII ecu for the 2jz? If so, that would be a good starting point. Done now....surfing on a blackberry hurts my head.

I wish I had spent more time with the simulators so I could reverse engineer things that would benefit us here but the president of my company needed a scapegoat to sacrifice to appease angry non-technical managers at carquest who couldn't figure out that six ecus sold to the same tech for the same car were indeed not bad since all six exhibited the same symptoms. Amazing how you can get in trouble for a customers lack of understanding but I am taking small consolation in the fact that they had to hire four people to do what I did for them. Rant over.....back to discussion. Lexus divides the 2jz into two banks so it shouldn't be too much a stretch. If not for variable valve timing and changing of indexing of the cams causing skewing of timing signals sent by sensors driven by said cams, it would be easy to use newer systems on older engines. This is why I mention the late single cam car models as a good place to start when looking for engine management systems that could help us with our non-variable valve timing engines. Any vg30 or vg33 car made later than 1997 should easily be OBDII so I will ztart there with my research now that I have lots of free time.

Edited out useless drivel that diverged from the topic.

In the test profiles we use at standard motor products with our ecu testing equipment, we usually just spoof the post cat sensor signal to the ecu in that the ecu only wants to see the very slightest of changes to prove to the ecu that the sensor is indeed working. Many of the tests we do have it at a steady value and the ecu doesn't complain at all. We also send the post cat signal matching the upstream sensor signal so we can whether the catalyst moniter in the ecu catches that the cat is not doing it's job. So it seems many ecus only moniter the resistence of the heater circuit and whether the cat is working. You can probably just spoof the heater coil resistence and get away with sending a steady signal in the range one would see from a sensor behind a working cat.......which normally is steady with near zero variance. I'll venture a bet it can be done with a resistor with the expected value on each circuit. I'll look into it more since it would be a lot easier than having to spoof all the signals one would need to spoof on a DOHC ecu to keep it happy.

I've seen threads on using Z31 or a hard to find M30 ecu on the L engine but none on anybody who tried an ecu out of the last couple model year cars that came with the single cam VG engine such as the late 1990s pathfinders, pick-ups, and quest vans. If one would go through the trouble for early consult capable ecus, then whatever capability they seek would be much better fulfilled with the above mentioned ecus......right? Just wondering. I'll try it myself and report my findings, I guess.

The best data on small port head performance can be found on a few oldsmobile sites that concentrate on olds 307 "y-code" engines. These engines came with purposely small port heads used in an attempt by gm to get mucho torque at very low rpms......and they do just that with the side effect of running out of breath at a lower rpm than most any other gm engine. Cars they came in routinely sported rear0end ratios in the 2.73 and much lower which helps all those gm full size station wagons get 20mpg on the highway. Whether this applies to the l engine geometry is a completely different story. It probably doesn't unless you come across such a head that nissan made for a forklift or other heavy equipment running on propane or lpg.

L28et into M30 back on track for pic posting in a week or so. Made oil pick-up, dipstick, and used front dump from l24e first generation maxima as well as engine mounts from same car. Test fitted fine but am using built 3n71b and will be switching out m30 diff (w inch longer than other long snouts) for one with a more common length before solidifying driveshaft length. That means some tranny crossmember work.

Nice.........I noticed that nobody here mentions that setup in the diagram but rather the two hose system from the 1981 and older cars.

Let us know what you want out of your car such as pounds of boost.......etc. It's possible what you want cannot be done with ecu tweeks.

Turbo oil drain?

I'm working on a flattop f54 with p90 that will be boosted to the point of encountering this problem. Since this engine is full of old and high mileage parts, I may substitute one or two dished pistons in 5 and/or 6 for kicks and post dyno and damage results..........might take a month or so though. It's not the solution but more of a workaround if it works and doesn't kill power/balance.......etc. You guys doing the research on this thread are heros and should get mucho credit (and money) if you find the fix.

Remove the cover over the ecu by the driver's left foot and wiggle the connectors on the ecu while driving. You might need someone else to watch as it's hard to see and wiggle them at the same tiem.

unplug the o2 sensor and see if it still does it.

What's the oem number on the ecu?

I usually use a very small dab on that small joint where the front cover meets the block because many people don't take off the front cover and I've seen a few where the front cover gasket is a couple of millimeters short of flush with the deck.

A co-worker put a kenne bell supercharger on his jeep and it came as a kit with much larger injectors. I figured he would be belching smoke and he did..........for a couple of drive cycles and then the car ran just fine with zero ecu tweeks and continues to be a daily driver six months later. The Jeep ecu is not to be underestimated in it's abilities......regardless of the fact that they were made with not so good components. I've been really busy trying to hire on another technical support guy at our ecu rebuilding facility but this needs more looking into. What I am finding is that chrysler and GM ecus are a whole lot more than most people think function wise. That said..............anybody have a 401 steel crank?

Just make sure you don't run a restrictive muffler.

Remember that the vg30 has a crossover pipe and the stock intake manifold actually sit over part of the tranny bellhousing. This means you will probably have to move the tranny back for any straight six swap.

LOL........this is a terminology argument that does not need to occur. When I was a marine mechanic for hatteras yachts, we had both intercoolers and after coolers.

A lot of toyotas come with them and I replaced them every time I did a clutch as most won't last two clutches worth of usage. If you look closely at the nissan bushing parts bag, it says "oil impregnated bearing" meaning that any wear will cause the oil that is impregnated within the bushing to lubricate whatever "liberated" it. I've never had a factory bushing fail but once did see one that was visibly worn after 280,000 miles of usage.

I've got a L28et in a M30.

I never knew why guys would shut off the alternator on a run when you can just make sure the battery is fully charged before the run. If battery is fully charged, you won't be using hp to keep it that way. This allows your ignition coil to start with 13.8. to 14.1 volts rather than 12.6 volts it would see with no alternator. That 1.2 volts can mean a lot to people with certain configurations.