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Sorry for the engine problems, Pretty sure you'll be back on the road soon. Pretty Crazy built!!!
 

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Discussion Starter #62
Results are in, 2 melted pistons and 1 that pinched the ring, all bearings still look new, hopefully .5mm overbore will be adequate.
The more i liok at it the more it looks like boiled fuel in the rail. I’ll be switching my non return fuel setup to conventional return style system, i also bought some egt probes, i purchased some barely used second hand cp pistons and i also got an msd fuel pump voltage booster for cheap i’m going to power my coils with.
 

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Discussion Starter #64
Parts have started arriving, i scored some slightly used forged pistons for cheap, main studs, 6x exhaust egt probes, my new 3.73 front diff (old one was 4.3 which is way to short) will be here soon then i’ll source a rear to match and i also got an msd fuel pump booster to use to supply my ignition coils with 14-16v
 

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Discussion Starter #65
My awd block is scored in the bore and will need 87mm pistons to bring it up to spec so after comparing my awd and rwd blocks i have worked out a way of using a rwd block with a few mods to address the differences and just use the 86.5mm pistons i already have. My turbine wheel also lost some material so i’ll have one of those on the way soon too. My ported head is also in need of some attention so i will put my cams and valvetrain into my spare stock head and use it until i get around to cleaning up the damage to the quench pads on the ported head. I’m still undecided if i’ll spend the money and get billet main caps, my goal of 750awhp should be achievable on stock main caps but its one of those piece of mind items for my power goals.
 

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Discussion Starter #67
I have worked out how to use a rwd block in my awd application, the block is machined ready for assembly. I have an event i want to go to so i have to get committed and knock everything out in 4 days. Ive got to assemble and dress the engine, drill and tap my thick wall stainless exh manifold for egt sensors, replace the turbine wheel in my turbo, reinstall the diffs, engine, gearbox and transfer case, axles and driveshafts, convert my fuel system from non return to return system, test everything is safe, give it a light road tune and pack it up onto a trailer and drive 500km on friday.
I havnt got ahold of a 3.73 ratio rear diff to match my new front diff yet so i’ll be sticking with the short 4.3 until after the weekend.
The new setup will be a rwd block,9:1 86.5mm cp pistons with hd pins, pro drag i beam rods, a standard head with my uprated valve springs and 276/276 cams, the rest will be the same as before.
 

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Discussion Starter #68 (Edited)
Heres a youtube page with a few of the cars my mates and i’ve done, we’ll be adding more content as we dig it up, we also have a couple of shitboxes under repair and a build or 2 coming up which we’ll chuck up there as well.
Cars include
My AWD IS300 ~600awhp
Kierins’s Candy Purple supra. (670rwhp in the vids, had made 850+)
My brothers 600rwhp white RZ supra and the build on his Black SZ coming soon.
Theres also a flood salvage supra we call swampy we’ll be getting stuck into before too long as well.
The link doesnt work so just youtube search pov300 or awd is300.
 

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Discussion Starter #69
Well, unfortunately i rushed the reassembly to make an event and believe i missed a final torque on a head stud resulting in blowing a gasket and torching the head. Ive been building a stopgap engine over the last month or so, ive been busy with new house stuff, new shed and new work ute kinda stuff so the lexus has been on hold for a bit. I bought a running engine for cheap, gave the bores a hone, cleaned up some stock vvti ge pistons i had, put some new regapped rings in with my i beam conrods, a new gte head gasket and my main and head stud kit, installed my cams and springs and some new valve stem seals into the new head and put it in the car, it’s nearly ready to start and should be running this weekend.
 

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Wow, really really impressive build. I can't believe the level of knowledge and ability this took in so many different areas (fabrication, electronics, engine, suspension, etc.). The thought has flickered into my head of making an IS300 AWD, but I know this is so far out of my league. Glad I can see someone else doing it, though!
 

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Discussion Starter #72 (Edited)
She’s alive, the cams are a bit noisey so i’ll have to look at the valve clearances again, otherwise its running fine.
I also found the real cause of my head gasket failure, the rad fan switch in the bottom rad tank failed, causing it to overheat, warp the head, gasket failed and combustion torched the head and split the radiator tank.
Fortunately i found the issue while trying to bleed the cooling system, i’m very relieved i didn’t miss that head stud and i found the issue so im not second guessing myself and my fuel system.
I’ve installed my 3.7 ratio diff gears into my front diff and am currently waiting on my rear set of 3.7s and rad fan switch to arrive so i can run the new rings in.
I also bought a new ute to get me to work and bought some Fuel 18x9+20 wheels which are Getting fitted next week and some other cosmetic mods like tint, sports bar, black out any chrome or silver, add a levelling kit to even out the rake then later this year i will probably make a compound turbo setup for the little 2.4 diesel. I could probably achieve the same thing with a conventional high flow single turbo/exhaust/flash tune but i like doing stuff thats different as you probably guessed so compound it is. So now i’ll have a graphite 4x4 with black wheels to tow my graphite is300 with black wheels to the track.
 

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Discussion Starter #73
The Daily with its new wheels. Unfortunately fastway couriers have lost my diff gears so everything is on hold until they find them as i installed the 3.7 gears in the front diff but still have 4.3 in the rear diff so other than driving it in and out of the shed short distances i’m unable to go and run the engine in on the highway.
 

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Discussion Starter #74
i have it all running again, diff ratio is now 3.73:1 my loose torque converter has 100kmh cruise at about 3200rpm compared to 3800rpm of the 4.3:1 set. The fresh engine is running fine, i had to reshim a few of the buckets in the head to get rid of some valve train noise and adjust the pinion bearing preload on my rear diff as it was a touch noisey. I’ve run the new engine in on 50/50 blend of 98/e85 on maximum of 18psi, even with the awd, 265 rears and 235 fronts it still has the traction light flickering at 150kmh indicating the traction control is taking action and braking wheels as required. It’s virtually un-noticeable handling wise when it is intervening. As of this afternoon ive run the tank right down and added e85 so over the next week i’ll try turning it up a bit on e85 traction permitting. Heres a pic of my matching work ute and race car. 😂
133130
 

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Discussion Starter #75
The new engine went great... until it didn’t. It cracked all the ring lands and burnt through piston 5 while afr were at 10.8. It appears i have a triggering/reference/timing drift issue that results in the engine seeing significantly more timing than called for or reported which is quite possibly causing this run of failures.
I did 10+ 0-200kmh pulls and everything was logged and fine, i put it on a trailer and towed it 500km to roll racing and it failed in under 9 seconds.
Current plan is to assemble a cheap disposable motor so that we can put it on an oscilloscope and check the crank reluctor waveform against whats reported in the ecu, closely inspect all of the wiring and connections, make a new tefzel injector harness, give control of the vvti to my aftermarket ecu so that it can monitor and log the intake cam position in relation to afrs and all of the other logged channels. If i am unable to track down an issue that i am confident is causing it my ecu will be sent away and run on a bench with a simulator program to test all of the inputs and outputs.
The biggest issue is that none of my failsafes catch it before it destroys itself due to it being timing trigger related and on e85 so there is no audible knock, afr, fuel pressure, coolant temp, boost pressure all log well within spec.
 

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The new engine went great... until it didn’t. It cracked all the ring lands and burnt through piston 5 while afr were at 10.8. It appears i have a triggering/reference/timing drift issue that results in the engine seeing significantly more timing than called for or reported which is quite possibly causing this run of failures.
I did 10+ 0-200kmh pulls and everything was logged and fine, i put it on a trailer and towed it 500km to roll racing and it failed in under 9 seconds.
Current plan is to assemble a cheap disposable motor so that we can put it on an oscilloscope and check the crank reluctor waveform against whats reported in the ecu, closely inspect all of the wiring and connections, make a new tefzel injector harness, give control of the vvti to my aftermarket ecu so that it can monitor and log the intake cam position in relation to afrs and all of the other logged channels. If i am unable to track down an issue that i am confident is causing it my ecu will be sent away and run on a bench with a simulator program to test all of the inputs and outputs.
The biggest issue is that none of my failsafes catch it before it destroys itself due to it being timing trigger related and on e85 so there is no audible knock, afr, fuel pressure, coolant temp, boost pressure all log well within spec.
You may want to invest in a good Pyro meter set. It will help with seeing issues like you are having. Should help prevent you going into melt down. If you pay attention to it.
 
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