1UZ-FE: 4.0L Lexus V8 dual distributors ???

shadetree · Post by **shadetree** » Sat Jun 18, 2005 6:23 pm

Hi.

I'm planning on using a Lexus V8 out of a LS400 or SC400 for my next project. It's a pretty cool engine: all alloy, quad cam, 32V, forged crank and rods, 6bolt mains, 6500rpm redline, 240hp.

As far as I know, no one has used megasquirt n' spark to control it.

It has dual distributors. I'm not sure how that will work with MSnS.

This is the factory wiring diagram for the fuel/ignition system
http://www.lextreme.com/lexuecc2.pdf
Any ideas. I am feeling a little overwhelmed.

Also, there are a freaking TON of sensors. main TPS, sub TPS, 2 main O2, 2 sub 02. Does MS support all these? Just ditch the sub sensors?
http://www.lextreme.com/lexecc1.pdf
It also uses a kooky Karmen Vortex MAF which I was planning on ditching for the onboard MS MAP.

lmr052 · Post by **lmr052** » Sun Jun 19, 2005 3:03 am

You may be in luck..... but you will need to do some investigations to see if you can run a similar setup to me

1 - Check how many teeth are on your Engine speed sensor (12 or 24?)
2 - Check how many teeth on on the sensors in the distributor (1?)
3 - Assuming one tooth in the distributors, check that these occur at opposite times to each other

If the distributor sensors are 1 tooth, each 360 crank degrees out of phase with the other, then you should be able to combine the G1 and G2 signals (pins 6&7) as a second VR input, and keep your engine speed - NE (pin

as the "normal" input.

You will need to build 2 VR conditioners - see the http://megasquirt.sourceforge.net/extra/wheel2.html

Be warned - you may need to do some experimentation with getting good clean signals - although your may be better off than me as your G- and NE- are separate. Mine shared a common wire leading to cross-talk.

Not sure about all those other sub sensors and the connection to the auto transmission.

Regards, Richard

shadetree · Post by **shadetree** » Sun Jun 19, 2005 12:17 pm

lmr052 wrote:You may be in luck..... but you will need to do some investigations to see if you can run a similar setup to me

1 - Check how many teeth are on your Engine speed sensor (12 or 24?)
2 - Check how many teeth on on the sensors in the distributor (1?)
3 - Assuming one tooth in the distributors, check that these occur at opposite times to each other

If the distributor sensors are 1 tooth, each 360 crank degrees out of phase with the other, then you should be able to combine the G1 and G2 signals (pins 6&7) as a second VR input, and keep your engine speed - NE (pin as the "normal" input.

Regards, Richard

Thanks Richard. That sounds very promising.

Unfortunately, I don't yet own a 1UZ. I was planning on buying a T-boned Lexus LS400 this weekend for $1000, but somebody beat me to the punch.

Rooting around on the lextreme forums I found this:

maxpower on lextreme wrote:The crank has a 12 tooth trigger and uses a reluctor sensor to send the info to the ECU. Behind each dizzy attached to the cam belt gear there is a "home" signal used for the sequential/multipoint injection, the dizzy home signals are 180 degrees apart and occur once each engine cycle ie every 2 crank revolutions. It is also a reluctor pickup.

Sounds like combining G1 & G2 as VR signal 2 could be a go.

I'd like to check out your setup.

lmr052 · Post by **lmr052** » Sun Jun 19, 2005 4:00 pm

Ok so the input setup would sounds very similar to mine except for the spark outputs... and that may be a challenge to keep the right spark going to the right ignitor.... maybe you could fool MS to think is running a wasted spark 4 cylinder set up... or beg for some custom code.

Do you my MSQ? Drop me a PM if you do.

Regards, Richard

em_knaps · Post by **em_knaps** » Mon Jun 27, 2005 4:09 am

Hey chaps,

i have been toying with the idea of using 4 wasted spark coils with one of these engines and making the silly dual dizzy cross ignition leads redundant.

im unsure how stable the 4 ignition output MSnS-E code is as i havnt dont any indepth investigating as its not a priority for me at the moment.

a friend of mine has one in his Hilux 4runner with a locally made aftermarket ECU which only uses one of the cam sensors.

they are a lively little engine.
u could use say 2 dual coil pack from a ford mondeo or simular,
or any 4cyl wased spark engine.

am very interested to see how u get on.

Daniel.

em_knaps · Post by **em_knaps** » Wed Jul 06, 2005 4:47 am

it got the better of me and i had to do some fiddling.

if you setup ur ignition as a 4 trigger output on MT

then combine the trig a and c togeather and the b and d togeather
you get 2 outputs reoccuring every 180deg

u need to set ur dwell setings to "minimal for hei4" and check the invert output section on the spark settings,
i dwell or 75% or 50% fixed duty are used the signals overlap and cancel each other out

im unsure how this will work on and actual engine

i am geting a good clean output at 17000 rpm using the stim and an oscilloscope to measure the combined outputs

is this going to work?????

Daniel.

subie4me · Post by **subie4me** » Sat Jul 23, 2005 4:59 pm

I just finished a 1uz project. The motor I had did not have a distributer on it. It had a 36-2 wheel on the crank. This motor was setup for marine use from toyota. I removed the old ecu and harness then welded on another tooth and reindexed the wheel so it would work with edis. I used the boost control function feeding a power fet to drive the vvt solinoids. The turbos had internal wastegates set at 10 lbs. Ford mustang 75mm aftermarket throttle body, and ford 40lb injectors. It is running on f&l 110 fuel in an offroad car. It runs pretty nice.

em_knaps · Post by **em_knaps** » Sat Jul 23, 2005 7:13 pm

the later 1UZ's might be wasted spark from factory,

the engine im using is a early 90's non VVT engine
the two dizzys are on the end of each drivin camshaft on either head.

i have a board built and running on my bench useing the combined outputs.
with stim for wheel setting on 4

seams to be working just fine,
cant wait to test it on an engine.

Daniel.

em_knaps · Post by **em_knaps** » Mon Sep 12, 2005 11:16 pm

Gordon,

project has come to a screaming halt.

due to other projects taking precidence
and the lack of a suitable test engine
i have however made a signal converter for the toothed wheel and the cam sensors.

i dont know how to maunipulate a pdf file very well but i managed to kindof scribble on one which i have attached to this post.

I have included the .msq file i was running on my test MS allso.

have a play and let me know how u get on....
your feedback will be important.

Also if you can tidy up the schematic nicer than the mess i made thatd be cool..

Cheers. and good luck

Daniel.

em_knaps · Post by **em_knaps** » Thu Dec 08, 2005 2:26 am

Gordon...

any luck with implementing the MS to a 1UZ-FE??

i have a VR conditioner daughter board made and have a 1UZ powered hilux in my workshop to hijack the sensors while it runs.
i will be doing this in the next wee while and seeing if i can get a consistant rpm signal.......

then ill find some suitable ignitors and try making the silly dual dizzy's run.

let me know if u have any info from your experiances.

was my modified schematic of any use???

cheers,
Daniel.

Post by **jsmcortina** » Thu Dec 08, 2005 6:38 am

In the Extra 027 code I added a "dual dizzy" feature. I have stim tested it and it appears to do what I was expecting. It requires the wheel decoder.
On the Lexus V8 is the 24/2 style double trigger dizzy which should be suitable. Using a couple of VB921 to drive the coils ought to work.

Anyone game for alpha testing this feature?

James

em_knaps · Post by **em_knaps** » Thu Dec 08, 2005 11:03 pm

count me in james...

i had sorted out the dual dizzy output phasing issues but i have not tested it just yet.
been busy updating my chev with a new hilux.....

the mods that i made requires a particular ignition module that triggered off a
"minimal for HEI" signal

i am dead keen to test ur 027 code as i have a imobile but running on a LINK EMS ecu. the link apears to only use one dizzy trigger tho.
so its 24/1 teeth every 720deg crank rotation.
would be usefull but one TDC signal every 720deg is a bit much.
anyways. point me to the file. and ill modify my MS again to suit.

nice one james.

Cheers,
Daniel.

Post by **jsmcortina** » Fri Dec 09, 2005 6:12 am

See the latest alpha codes:
http://megasquirt.sourceforge.net/extra/files/alpha

Buyer beware, untested etc. etc.

James

buck19 · Post by **buck19** » Wed Dec 14, 2005 7:03 pm

Are they internal coil distributors. How would two standalone ignition modules workout?

This is all jibberish to me. I have a lot to learn.
How much do used Factory 1uz none VVTI ECUs and Harnesses cost?

em_knaps · Post by **em_knaps** » Sat Dec 17, 2005 2:11 am

buck19,

the dizzys are not like a normal 4cyl dizzy
the each have a vr sensor and a single tooth which gives a signal every 720crank deg.

this combined with the 12 teeth on the crank angle sensor is how the standard ecu makes calculations on when to trigger the standard coils and the 4 injector channels that the standard ECU has.

in NZ stock car racers use 2 identical toyota 4K dizzys and a carb.
the dizzys are mounted on the rear of the head which is difficult if u dont have the room.
this is so they can keep to the "no EFI" stock car racing rules.

the standard ECU is ok if u run with the standard auto trans,
they are next to useless with a manual as they get info on load and roadspeed and crap from the trans and expect a gear selection signal.
not sure how much they cost tho.

hope this helps,

Daniel.

Post by **jsmcortina** » Sat Dec 17, 2005 3:29 am

em_knaps wrote:buck19,

the dizzys are not like a normal 4cyl dizzy
the each have a vr sensor and a single tooth which gives a signal every 720crank deg.

this combined with the 12 teeth on the crank angle sensor is how the standard ecu makes calculations on when to trigger the standard coils and the 4 injector channels that the standard ECU has.

I'd like to think that my code could work like that too.

James

em_knaps · Post by **em_knaps** » Sat Dec 17, 2005 3:45 am

how does it work?

does it replicate ignition setings C and D on channels A and B?

ive yet to bench test your code james but found the "dual dizzy" option and enabled it.
but thats about as far as i got....

am i missing something?

Cheers,
Daniel.