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Discussion Starter #83
I’m not sure what it came out of, i bought it on ebay, it was listed as 3.73 awd lexus front diff, the pics looked close to what i had so i bought it.
Im sure some googling awd lexus models would show their final drive ratios.
 

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Discussion Starter #84
I think i have worked out my issue (with the help of some very intelligent people) , currently my setup uses an autronic sm4 ecu parrelled with the stock ecu sharing some sensors. My stock ecu controls idle via a 2jz gte etcs-i dbw throttle body (it has a premium japan manual kit in it), vvti cam position and the interior multiplex stuff like gauges etc so i can retain the stock interior and functional gauges without having to add an aftermarket screen.
I worked out how to log vvti intake cam position on my autronic so now i have a pretty good idea of the stock vvti cam position tables.
cam sync was also out by 335deg and injector timing was also incorrect.(neither of these effect ign timing but i corrected them while i was going through my data).
The thing i believe was my issue was just way too much timing in the zones from 7-14psi up to 5000rpm, unknown to me until now my vvti cam advance was still very aggressive in that range to the point where it really needed way less ign timing in that area. (I use lots of timing normally to get it up on the converter). Being on e85 meant it wouldn’t detonate but the extreme cylinder pressure generated from firing the plug 6-10deg too early knocked the ring lands off, once that happens oil starts passing the rings and at high power it lights off and melts things very quickly. Theres not really any way to tell if its completely fixed other than its still running in a few months. Im cutrently just daily driving it on 18psi on pump fuel. When i get some e85 again in a few weeks i can turn it up again and hopefully it survives.
 

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Glad you found some (hopefully all) issues and sorted them out!
I'm not very familiar with the Autronic ECU, from memory it cannot do VVTi or DBW? Can the ETCS-I throttle work without the stock ECU with the manual kit in it now?

Regarding the dash and multiplex stuff, not sure if you know about this, https://all4swap.ru/product/is300
If you want to get rid of the stock ECU and have most of the factory functions working.
I think you will lose traction and stability control though, which by the sounds of it you rely on to keep power down haha
 

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Discussion Starter #86
The sm4 can do vvti but not dbw. The dbw throttle with the manual kit works fine its just the idle control that stops working so i have to open the throttle stop screw and control idle stability with an idle speed delta table.
Before i remove the stock ecu i will cut all of the parrallel ecu shared sensors from the stock ecu 1 at a tume and allow the SM4 to control all running of the engine with the stock ecu and see what happens, seeing the abs/vsc ecu is a separate computer it is quite possible that i can find any outputs from the stock ecu and simulate them with the SM4, alternatively with the stock ecu still plugged in but in limp mode the abs/trac ecu may still use the brakes as the primary means to control wheelspin/slip ratio as the dbw is in limp mode and unable to control engine output. I should know in a week or 2 if i still have abs/trac functionality.
 

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Discussion Starter #87 (Edited)
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now i feel i have my piston failures sorted im doing what i hope is my last engine build for a while.
I’m building a tight quench, low compression 8.6:1, standard stroke engine.
New long block will be as follows:
2jz ge rwd block decked .016 and modified to suit my awd application. Spool pro drag i beam conrods with 7/16 arp2000 bolts, stock crank, stock main bearings, acl race .001 extra clearance rod bearings, wiseco 86.5mm 8.5:1 forged pistons and .200 wall thickness HD piston pins, stock main caps with arp2000 main studs,
2jz ge vvti head, BC valve springs, BC Stage 3+ 276/276 cams, stock valves, oem 2jz ge head gasket, CA626+ head studs, stock Awd GE oil pump.
The rest of the setup has had a couple of changes and will consist of:
Thick wall stainless exh mani T4 divided with 6x egt sensors, garret gtx4202 1.15 rear, tial 45mm wastegate to atmosphere, 3.5 inch exhaust with 1 resonator and 2 mufflers, custom top half ffim, stock modified fuel rails with 1400cc injectors (4 bar base pressure making them 1700s), R35 GTR Ign coils, adjustable cam gear on exh side, vvti intake cam gear, 2jz gte etcs-i 70mm throttle body with manual dbw delete kit and 70hp dry shot nitrous nozzle installed, custom ETS evo ix 3.5 inch wide tank intercooler with 3 inch in and out, 3 inch stainless intercooler piping, 5 inch intake. Built, full manual, transbraked, th400 transmission with resplined output shaft to mate with nv125 transfer case, tce 1200hp 6000rpm 8’ torque converter, custom chrome moly prop shafts front and rear, 3.73 front and rear final drive gears, plate type lsd in rear diff, 2x380lph external fuel pumps, 1x 320lph in tank pump, -8 feed and -6 return fuel lines, fuel lab fuel pressure reg, fuel cooler on return line, 326mm front brake upgrade, stock awd toyota crown dampers with lowered springs, Impul lightweight NS-GT2 wheels 235f 265r for street and Evo IX Enkies with hoosier 245/45/17 DR2 drag radials for racing.
 

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Discussion Starter #89 (Edited)
A few days ago i picked up a set of Genuine Rays Engineering Volk RE30s on fb classifieds, the seller obviously didn’t know what they were as they bought a car with them on but didnt like black wheels so sold them. I gave them a good clean and i’ll do some brush touch ups on the chips from useless tyre fitters using rattle guns on the wheelnuts. Fitment is spot on too. 18x8.5+30 235/40/18
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Discussion Starter #91
It’s not removed, it just has nothing to do with engine control, it still has sensors connected to it but has no effect on anything that runs the engine. My fuel gauge is shit now but everything else works, i’m yet to see if vsc and abs still function, i know vsc will not be able to shut the throttle as i manualised it ages ago but hopefully the 4 channel abs will still brake wheels should they encounter wheelspin.
 

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My fuel gauge is shit now but everything else works, i’m yet to see if vsc and abs still function,
Read up on a p1300 simulator and have the factory MAF plumbed and reading from your charge pipe. Those two things will get your fuel gauge back, if you care. The Lexus calculates fuel consumption and compares it against the float data. You’ll probs want to do a MAF clamp too. It’s still not perfect but it works pretty close to stock.

I have no idea how it turns the low fuel light on. I’m guessing it’s calculated as well. It does not have a thermister-type sensor like most low fuel light setups have.

Glad to see the project is still alive. This car is really badass!
 

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I have no idea how it turns the low fuel light on. I’m guessing it’s calculated as well
I have wondered about that one too, seeing it sometimes come on with about 1/8 tank and other times almost at the empty mark. I had just thought it was just a sloppy sensor, but i guess makes more sense that it tries to calculate it for you.
 

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Discussion Starter #94
Ive made an igf sim circuit and had the afm plugged n and the fuel gauge worked so i may plug the afm back in at some stage.
Another interesting effect, When i switched the vvti control over to the aftermarket ecu i needed a 12v ign power source so i just borrowed the 12v signal from the stock inj harness on cyl 1, now my fuel economy meter moves based on what the vvti action is. 😂
 

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Discussion Starter #95
Ive completed my road tune on 98ron pump fuel, 18psi, 9deg @ peak tq and 12 up top so its very conservative for a 9:1 comp engine. My vvti map has a whole lot less intake cam advance than the stock vvti map by 15cam degrees and also during vvti action i have about 10deg less ign than i previously had, these factors are what i believe was causing high cylinder pressure very early and knocking the ring lands off the stock pistons.
I am currently running the tank down than adding e85 repeatedly to dilute the 98 out of the fuel system so i can do the e85 tune.
Currently on e65 i am running the same 18psi boost but with timing at 12 at peak tq up to 16 up top. In this state of tune it is just on the limit of traction from my street tyres. (235/40/18). Previously on this boost and timing on the dyno it was at 437awkw on a dyno dynamics dyno (587awhp Mustang), keeping mind that is through a 6000rpm converter and th400 and awd, we have calculated drivetrain loss at about 150hp so 730ish on gate pressure leaves a fair bit on the table.
Due to already reaching the limit of traction i may have to put my hoosiers on and go do some late night data log pulls. (Drag radials are illegal for street use in Australia, especially slick ones with no tread)
I’m still getting around to fitting my dry nitrous kit, it really doesnt need it to get up on the converter from a roll so it hasn’t been a priority.
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Late night data logs are the best! Good to hear you’ve got it sorted. That thing looks like it came stock with a turbo it is so clean under the bonnet. I bet your ABS relo was pretty easy since it’s rhd. Mine not so much since it’s lhd, lots of line routing and not as clean.

What’s the yellow dipstick in front of the turbo? I’m guessing oil because the intake mani is in the way?
 

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Discussion Starter #97
Abs is in stock location for rhd model, no relocation required.
Yellow dipstick is engine oil, awd sump is center pan rather than front or rear due to the awd subframe, awd have it on the exh side as the intake side has the front diff etc so its pretty busy on that side, i tweaked it a bit to clear my 5 inch intake when street driving, i run a 5 inch intake with catch can plumbed back and a big K&N filter.
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