550hp 2JZ 1978 Hilux Build

She runs!

Went pretty hard on the truck last week, though doesn't feel like it and not a lot of photos. The main thing was getting the wiring wrapped up. The first time I wired the Hilux I had a million fuses and relays, this time I combined a lot of wires together and only have two relays. One fatty 75A ignition relay, and then a 35A high beams relay that plugs into the fusebox. I used a lot smaller fusebox too, so maybe 10 fuses total. Everything has labeled heat shrink on both ends, and as I said a lot of lines combine so for example the high power engine bay stuff (injectors and coil packs) are all on a single wire, all the miscellaneous lighting like running lights and brake lights, hazards, etc. are all combined to a single fuse.



This is mounted up under the dash above the passenger floor board. The wiring is broken into two legs, engine all runs out/down the passenger side of the vehicle and lighting, brakes, anything else is run through the dash and down the driver's side of the vehicle. The two legs are 100% isolated from each other, so if I want to change a major system I don't have to tear everything down or dig through an unrelated loom.



I don't know if I talked about the rest of the wiring earlier, and since the majority of this upgrading is wiring I'll give some more details on that. At the battery (located at the back of the truck) I have a 150A breaker that all positive power goes through, it's kind of a middle ground from a straight up kill switch since it can only be accessed externally, but it can be used to kill power to everything which is nice. From there I run positive power in a loop around the truck, to the starter, then daisy chain to the alternator. At the alternator I also have a branch that comes off and that's what goes to the above ignition relay. For grounding I have a short leg come off the battery and ground to the chassis, and then another leg runs up the passenger side to the engine head, where all of the ECM and engine grounds go to, as well as another big leg that goes to the body.

Mounted to the battery box I also have two 40A relays that control the fuel pump and radiator fan. I put these in the back because those two functions are at the back of the truck, so this keeps all the relay wiring right next to the battery and then a small signal wire from the ECM runs to the relay.

With all of that said, once I got the fusebox wired we had a successful test of all the subsystems! For the first time the truck had high beams and low beams, plus all the other goods working correctly! The ECM also booted up for the first time, I updated the firmware and loaded an initial tune into it and went through the first start checklist which everything went great! Though I did not fire the truck up yet, but timing all lined up with the timing light and everything else functioned correctly. The ECM is really cool, you can individually command functions for checking things, like you can tell an individual injector to pulse 10 times. Makes it really fast and painless to confirm everything is wired up.

Next up was finishing the turbo plumbing, which would let me do the coolant plumbing, which would let me start it!





I used 3.5" 304 stainless to build the exhaust. This isn't the final ending point, but there is a crossmember after this point so I'm waiting on a V-band so I can split the exhaust in half. I also had to extensively rework the coolant pipes, modifying the thermostat housing multiple times and chopping up the rear coolant line to move it closer to the frame to give the exhaust room.

I then welded up this section, I was going to be lazy about it but decided to back purge it since I would only have to do it once, and then zoomed through it.





Which does make the inside look real pretty even if it's kind of overkill for what I'm doing! But I spent a good bit of effort on this so may as well do it right!



With the exhaust and coolant done, the remaining task was getting the turbo setup. The oil drain line ended up being the bane of my existence trying to get something that fit. I ultimately took the oil pan fitting and reworked it on the lathe and rethreaded it to AN10, took a hardline turbo drain line and chopped it up a bunch and welded an AN10 bung to the end, repeated that process again, and then made an AN10 line to connect everything.







You can also see the thermostat housing that I reworked a few times to get it to point where I wanted so the AN20 fitting would thread on without being an absolute bitch.

I also didn't take any photos, but as you can see above somewhat I welded a new bracket on the turbo for the wastegate so that was a bit of a process too.

All of that covered a few days of work! Just for the engine bay to look about the same!



That brought us up to Sunday, at which point I finally tried to start it! And it would burble for a moment and then not fully catch. That seemed like a good place to end Sunday, so I could focus on tuning it Monday.

Monday ended up being a complete cluster fuck struggling to get the engine to even catch. My buddy and I spent 7 hours fucking with it, asking on facebook, browsing forums, etc. The issue we were having was the truck would fire the ignition coils but the instant it would catch it would stop firing them. So you'd get one combustion event and then nothing. And we tried everything to figure it out, disconnected the fuel pump, disconnected the injectors, hooked the coils to their own battery, etc. and it would be totally fine and then you spray some starting fluid and a burble and then no spark. The one guy on facebook that responded to our post said we should log primary trigger errors, which ended up pointing us in the right direction that there was an issue with the crank shaft trigger.



This was the scope we were getting of the crankshaft trigger, which I thought was fine since it counted correctly, but datalogging trigger errors the ECM was throwing a "missing unexpected tooth" error and I was able to find some information that the two spaces next to the lines with circles was wrong. The crankshaft has two missing teeth on the trigger wheel, and the scope shows two missing teeth but show that one tooth with the circle between the two missing teeth, when the two missing spaces should be side by side.

I still wasn't sure how to fix this, there were two base maps from ECU Masters for the 2JZ and both had the same primary trigger values, which also matched my crank. I even took the front cover off (I've gotten very good at that) to clean up the crank trigger teeth and make sure I had counted the right number of teeth, and everything seemed fine. The guy that had been trying to help us was at a loss also, so at this point I just started fucking with the primary trigger settings to see if I could make it work, and long story short that eventually worked!



For whatever reason, changing trigger edge from "falling" to "rising" fixed everything! 7+ hours of fucking with it, and literally that one setting changing fixed it. I still don't know why that fixed it, none of the base maps for the 2JZ have it set to rising, but changing it to rising made the missing trigger teeth show up side by side on the scope so now the ECM knew where the start of the crank revolution was, and that's all that really matters since I can adjust everything around that if need be. But doing that and it fired right up!

We only screwed with it for an hour or so last night after it fired. I had to crimp the injector/coil wire back together since it was still running on an external battery, hook the fuel pump up, etc. and undo all the troubleshooting measures we had done. I then got it idling somewhat normally, and got the cooling system bled, and called it a night after that. Right now it won't rev out of idle, so time for some more reading and getting the fueling dialed in and actually tune it---what I was hoping I would be doing yesterday instead of troubleshooting weird trigger issues!

I will say this ECM is really cool, and a totally different animal than the Holley stuff I've worked with. Since this is a much more universal ECM than a Holley, you have a ton of control, but it's also more difficult to find information because of that. At a minimum yesterday taught me how to use an oscilloscope to confirm the ECM was sending signals and I used a timing light more in one day than I had the rest of my life combined! Next up will be getting it running and driving and dialed in, and once I get the V-Band for the exhaust I will finish that out which will look pretty cool.

 

Lots of progress! Last couple days have been a focus on finishing the exhaust since I got the 3.5" V Band I needed, and then more tuning.

This guy was fucking stoked





And here's a random photo of the turbo oil drain:



With the V-Band and some more pizza cuts I went about mocking up the rear section of the exhaust which was quite the animal.





Just getting the V-Band on was a trick and required some angles on both parts of the exhaust. It is SO tight here.



And I learned that the easiest way to assemble/disassemble is to disconnect the V-band on the turbo, and then pull the crossmember that the exhaust goes OVER, and THEN it's not too painful to get the V-band clamp on (of which I modified to make it easier also).

All of this work so I could have a high clearance exhaust (the transmission hangs lower by quite a bit) and then have a cool bedside dump into a teardrop shape!



With it all tacked up, and a pain to remove, it was time to weld it up.





The front part of the exhaust generally welded a lot better, not sure why. Though to be fair I did absolutely zero cleaning of the metal, but I did back purge it. Not the prettiest welds, but they'll hold. I welded on it for 3+ hours straight, and that was zero prep of the surfaces, not even wiping them down. There was a LOT of seams, and with it being so big I only stopped at one part to let it cool down for a few minutes since generally I could bounce between the two ends and weld one part while another cooled. The exhaust tip turned out pretty sick.





And back up she goes, tight is the name of the game!



I have the exhaust hugging, if not outright touching, the engine and transmission the whole way to try and give some room for the body and the cooling line and wiring. I then went in after and wrapped everything in aluminum foil as a temporary stop gap until I get some proper header wrap.

The bedside I cut with the plasma. I have two overlay plates that will clamp the bedside and hide the gross cut on the body, but I haven't put those on yet since I wanted to get it actually driving now that the exhaust was finished.



The exhaust tip sticks out a bit, I will hit it with the grinder so it ends up flush with the bed side.

I might move the battery someday, we'll see how hot it gets back there. I originally put it there to offset my weight. Once I header wrap the whole exhaust I'm not too worried, and there's a lot of airflow with the open bed. You can see I have two rubber exhaust hangers, one next to the driveshaft and then another near the tip. I might have a little arm come out to brace the exhaust overlay plate on the bedside too, we'll see how much it moves around and gets caught on the exhaust.



And this is back from the first drive!



Yesterday night and this morning I tried to get it to run correctly. Originally the engine was surging, was in this constant loop of revving up then down on repeat. I got that fixed at idle by closing the throttle body all the way, which I originally had opened a hair since it's a little sticky at full close--but that fixed the idle for the most part. But revving it up it would go back into the surging. I watched videos, read posts, and I couldn't find anything related to the problem I was having. Watching tuning videos just showed what I already knew. I sprayed starter fluid all over, I fucked with the MAP vacuum line, this morning I even pulled the intercooler off to make sure the throttle blade wasn't doing some weird resonance and the turbo wasn't causing it.

I decided to check the timing with the timing light again, and for some reason it was off by 6-7 degrees mechanically from what the ECM was commanding. I thought that was weird, but I had changed the primary trigger tooth setting from falling to rising, so maybe that had affected it since it was reading a different part of the tooth presumably? And that reminded me that you could change that same setting in for the secondary (cam) trigger! I swapped the secondary trigger tooth from falling to rising and voila the truck runs perfectly! I had also noticed the camshaft timing was reading weird pulsing values that coincided with the surging, even when I would turn VVTI off, and with the trigger changed that fixed that also! So for whatever reason, my 2JZ runs the 2JZ basemap settings for some things and is 180deg different on other things! Which is crazy, literally two menu items that swapping them in the tune fixed everything, and if I had done that first would've saved me probably 15 hours of troubleshooting in the past week!

With the updated cam trigger settings, I was able to open the throttle body up again so it wouldn't be sticky and it idled great! It would rev up fine, everything was working so I took it for a drive. First around the neighborhood, then got gas, made some more tweaks to the tune, and then drove into town a bit, more tweaking, and drove home.

There was some weird things though, the turbo seemed to make this high pitched squeal at certain rpm. The turbine wheel had a fucked up blade, so I figured it was just that making noise. But on the return from town I got into boost for the second time and heard it spool up and then a high pitched suction sound, and a puff of smoke! I wasn't sure if the engine had exploded, a boot had popped off from boost, or what, but the truck was still running fine and had oil pressure so I continued home. When I got home though, the compressor wheel wasn't spinning at all. I just took it apart, and the compressor wheel can free spin on the shaft and actually the turbine wheel spins fine too.





I think part of the turbine wheel came off, and jammed the turbine, and the compressor momentum loosened it (it's only held on with a nut). The turbine wheel is well chewed up, and seems to have bent the shaft since there's quite a bit of run out.



I pulled the shaft, which also ended up breaking the end pulling the nut off (so it wasn't getting tightened back down anyway). I'm hoping my neighbor has a spare shaft/turbine wheel lying around since the rest of the turbocharger seems fine. We already knew this turbo was going to need some refreshing, I just didn't think it'd need it THAT fast.

But otherwise lots of success! The truck and ECM are finally running correctly. I need someone to take me for a drive so I can adjust the tune and get some steady state load on it. I made 6.2psi on the second pull when it blew, and when the turbo comes on it's insane feeling. There is so much power, I thought I was going to have the rear tires break free at 60mph. One of my friend's was saying that if I had an electronic wastegate it would help it spool up faster since it would only bypass air when peak boost was hit, instead of the mechanical wastegate that is throttle dependent, so I might go to one of those sooner than I was thinking. I only got into boost twice, but it really needed some rpms to get going. The second time when it made 6psi it was at 6400rpm:



And the first time it was near 7000rpm, so it really needs to get up there to get the turbo going. But in some ways that's nice, the truck feels totally normal driving around until you go WOT and give it a second for the turbo to spool up. I just wished it was a bit more linear power delivery, but I only have one drive a lot of tuning to do still so we'll see if I can dial it in and get used to it. Can always run a different turbo setup too.

Hopefully next update is all about tuning and getting it dialed in driving. Turbo might be fucked, but the Hilux is back in action!

 

That @snivilous, damn he does nice work!

 

Put a leash on that praying mantis and keep it for a mascot ! That MFer is huge

 

Or a saddle.

 

Doing some sniv speed shop swag with a praying mantis would be kind of dope, I think they're one of the coolest insects. I only see one once a year or so, this dude chilling in the shop was a good start to the day!

 

What a sweet build! Nice work!

That late spool might be related to the failing turbo? Bent shaft slowing it down or something. Shouldn't take 6000rpm to build 6psi even on a massive turbo...

 

My neighbor also theorized the waste gate could be set too loose and bypassing exhaust right away I guess? On the upside, he talked to two guys at work and one might have all the parts to fix the turbo, and another guy has a similar turbo that would just need the waste gate moved but will bolt up with the exhaust.

 

Excuse me but it looks like you’re sitting down in this picture. Unacceptable! Kidding aside, great work. Jealous.

 

Possibly. Usually the gate just has a set spring pressure and when the boost pressure overcomes that spring pressure, the gate opens and starts to divert gasses. Usually there is a minimum boost amount before it is able to start opening. Could be weak spring or faulty diaphragm or something. Or maybe it operates totally different for diesel applications lol

Good news about the possible replacement parts

 

Will post a proper update when I have time, but a quick clip for your ears enjoyment:

https://youtu.be/Gxut7UFi8-M?si=9PpJ2DeyryOEBdkP

 

Dooooooooood. That’s sick.

 

Sweeeet!

 

Rocket! I expected to hear a maniacal laugh!

 

Fuk yes!!

 

It will be a rocket once it gets some decent tires. I tried to do a 0-60 with the dragy today and it spun through every gear

 

Sniv's Sunday Storytime!

A lot has happened in the past week, we'll see how much I remember to write down. We left off with the first turbo having issues. I was hoping I could replace the turbine shaft, but it ended up that when the thing went poof and the compressor wheel got loose that it had moved forward and started rubbing on the compressor housing, which the housing could be fixed but the wheel was toast, so I would need a whole new core section to replace it.





After coordinating with people my neighbor knew (he works at a diesel shop, thus why I'm getting free diesel turbos), I wasn't able to get parts to fix the first turbo since it's a tweaked one with a different compressor/turbine wheel setup than a factory turbo. Luckily, his brother had a turbo laying around that he said I could have!



This one is a HE341, which I guess was only offered for one year on the 5.9 cummins before being changed out for the HE351---the first turbo was a modified HE351 with a larger exhaust turbine. That last point being critical, and overlooked by myself and everyone else.

I had left the exhaust housing on the engine, no point in unbolting it from everything when it had the same bolt pattern as the new turbo and presumably would work with it. I took the "new" turbo apart, rewelded the wastegate mount onto the inlet housing, and then installed it into the previous exhaust housing.



This turbo made no boost whatsoever. Fast forward some fucking around, and then the epiphany that even though all the mounting interfaces are IDENTICAL, the HE341 has a smaller exhaust turbine than the MODIFIED HE351 I was running, so obviously there was no boost since the exhaust was just skirting around the turbine and not actually spinning it. I then pulled the turbo apart, cleaned up the correct exhaust housing, bolted it all together, etc. etc. ANNNND it still makes no boost.

Pull the second turbo apart, and the turbine is rubbing on the exhaust housing and dumping oil.





No one seems quite sure how it made no boost at all, it would still spin up fine and had a squeal to it, but somehow refused to make boost. The shaft had quite a bit of run out and had gotten bent somehow, presumably before I received it. I think this updates us to like Sunday last week. So at this point, I've gone through two free turbos, and I could buy a new turbo from the diesel shop which was expensive plus they didn't have any in stock for a size that everyone thought would be good suited for the truck. Thus, on Sunday I bought a chinese HE351!



Three different turbo setups in that picture that the truck ran within a week span! The modified HE351 for the diesel guys on the top right, the old HE341 for a stock 5.9 cummins, and then my new stock HE351---also for a 5.9 cummins. But the diesel guys thought that the modifications they do to their HE351 on the exhaust side was actually detrimental to me, which is why I didn't just buy one of those from them and went with the stock style HE351----plus this bad boy was $140 shipped!

And fast forward a bit, reweld the wastegate bracket AGAIN, and we finally have a functional turbocharger that hopefully lasts!



Almost everything about the new turbo looks identical to the first turbo, I wouldn't be surprised if they are essentially identical. I won't be pushing this turbo with much boost, so between that and everything looking solid, I'm not too worried, and for $140 can't go wrong---and there's an intercooler to filter stuff at the intake hahaha

Time flies, I think the new turbo was installed on Friday since there was a car meet in town with a bunch of out of town drift cars showing up so I took the Hilux to that which is when that video I posted was taken.



A lot more screwing with stuff than I was expecting, but finally has a good turbo and runs awesome! More tweaking of the tune to get it dialed in more, and probably have 100 miles on it with the new ECM and everything is working great! The power is absolutely insane, boost comes in around 3000rpm and then it just lights the tires up, but it's not an abrupt hit and feels like a nice and progressive increase in power. But trying to launch it is impossible, and full throttle even rolling from a slow speed, once it gets deep into boost it'll spin through 4th gear and then I let off since it's terrifying. I did one half hearted 0-60 pull where it was like 6.5s which isn't bad, but the entire thing was just babying the throttle trying to prevent it spinning which it still did. Tires and wheels are high on the list, so none of the spinning is really a surprise.

With that said, there are some "big" issues. At first the turbo seemed to be making like 12psi of boost. I wanted like 7psi which is what I had read people said the stock NA 2JZ could handle. I kept backing off the wastegate, which for anyone who's like me and doesn't understand how a wastegate on a turbo works--it's closed initially which forces all the exhaust through the turbine to spin it up, once a certain amount of boost is built, the wastegate starts to move which opens a flap to bypass exhaust around the turbine which stops it spinning up so the boost doesn't increase---well I kept backing the wastegate off to bypass more exhaust and it didn't seem to do much. And on top of that, I hadn't actually used 100% throttle and held it. Well I tried that yesterday during some tuning, and it made 20+ psi!

I even backed the wastegate off more, to the point it's wide open so it's bypassing as much exhaust as possible even at idle---still made 20psi! The issue is the turbo is meant for 40psi on a diesel, so I'm trying to limit it way beyond what it wants to do, there's physically no way to make the turbo put out less boost without drilling out the wastegate port to try and allow more exhaust flow (soon to happen).



And 20psi on a built 2JZ is great, that's what I want down the line, but right now I need a lot less than that! And I may have gotten too frisky right away.... I took my neighbor for a rip today, and during a pull there was a puff of smoke from the front. When we got back to the house, it seemed to have come from the crankcase vent. But she was still running fine. Then a friend stopped by who was driving by and I took him for a rip and just let it eat to show him how wild it was to spin through four gears, huge puffs of smoke. To the point of oil covering the windshield at the end. But truck is still running fine, get home, and the crank case vent had absolutely puked oil out of it.



On the down side, I don't have the catch can hooked up, but the plus side was I could see it blowing all the smoke to know something was up?



Get home, running fine, turn the truck off, inspect stuff, seems alright---go to start it and won't start!

This was like an hour ago this happened.

We pushed it back into the shop, and I pulled the plugs and did a compression test.



Plugs look fine, a bit rich which I was expecting but no oil on them and not lean by any stretch.



Check compression, for reference what it was when I first measured this engine like two years ago:

1 - 150
2 - 130
3 - 110
4 - 90
5 - 70
6 - 150

And now?



Cylinder #1 is certainly hurt, but the engine is actually running better than ever! I think the rings were maybe seized up when I got the engine and have broken free since the compression is actually amazingly good now! Not at all what I was expecting.

And that's where I called it. What's next? I will reinstall the plugs and see if it starts, I don't know why it didn't start in the first place, five good cylinders should start easily. This of course was the one drive I've done without the laptop (since I don't have a dash yet) so for all I know fuel pressure was low, or one of the engine fail safes decided to keep it off---but it shouldn't be compression related at least which is good!

After that, I'm thinking of pulling the head and pulling piston #1 and actually swapping it with a piston from my spare 2JZ. The 2JZ oil pan is this weird two piece thing, and the bottom piece only covers the front four cylinders, and I don't think (albeit have yet to try) that I can pull the upper half of the oil pan with the engine still installed in the truck. Meaning, I can drop the pan easily, pull the head, and pull the #1 connecting rod and piston without pulling the engine. But since I can't access the back two pistons that way, and I don't know if I feel like pulling the whole engine right now, so as a quick and dirty fix I can swap just the #1 piston and do a quick ball hone on it and fix whatever is wrong with it and slap it back together.

Another option or two, is if I can access the connecting rod bolts for the rear cylinders, then just swap all the connecting rods and pistons to stronger/low compression ones without dropping the engine. If I can do that, I think I'll definitely do it since that's the main reason to build an engine is to lower the compression ratio and get stronger connecting rods (the NA 2JZ ones are known to be weak). I wouldn't get all the fancy block work done, but that's why I bought a second engine so I can do that later (if I really care to even). The second option, is I could just pull the whole engine to do what I just said anyway. At the end of the day that's a couple hour job, the harness unplugs easy, I'm going to pull the turbo and exhaust ANYWAY to heat wrap it and drill out the wastegate port, I'm gonna have to pull the intercooler and crank pulley to get to the timing belt... so pulling the engine is really just unbolting the bell housing and intake and harness at that point.

Which typing it out, seems insane not to just do a quick build of the engine, it's like $1500 for new pistons/rods/rings and then it should be able to handle whatever I throw at it. As long as the block doesn't need to get honed, that's probably what I'll do. If the #1 cylinder walls are jacked, then I'll probably just slap it back together and send it while I start building the other engine and drop it at the machine shop. But if I can avoid needing to wait on the machine shop, then I can have the bottom end built by next weekend and then run the full 20psi the turbo is putting out and everything will be happy.

Stay tuned! Lot is happening

 

Wow! 20psi...
You should be able to at least take that #1 piston. But you'll most likely pull it and do them all. Haha

 

That'll buff out

 

Maybe a better question is will the wife let me swap all the pistons or poor boy it and grab one from the other engine

 

lol I want 7psi no sir you get 20psi enjoy ha

 

A lot of the N/A-T guys will swap in a TT oem headgasket which is 1mm thicker than the n/a gasket to drop the CR to around 9:1. I put a 1.6 or 1.8mm (I forget) cometic gasket to drop my JZ to about 8.6:1. Good excuse to do ARP head studs at the same time and take care of two issues at once. If you can get your hands on non vvti or TT rods they are much stronger. Just the vvti n/a have the wimpy rods. Could be a cheap upgrade. Guys are making 700+ on the setup listed with the stock pistons. (With good fuel or meth). Perhaps you can fab up and run an external waste gate on your manifold? Would have better boost control, less creep. Could be setup to run off a solenoid that you can fine tune with your ecu master. Then you can block or weld shut that internal gate. Sorry to hear about your hurt cylinder, maybe you can get lucky and put new rings on that one piston, fresh hone and send it? Just some ideas anyways lol great progress man!

 

I didn't realize you could drop the GE compression that much with just the gasket! I did a leak down test last night and it confirmed all the leakage out the breather is from #1 through the crank. I have a friend coming over tonight with a bore scope, if the #1 cylinder wall looks fine (which I have a feeling the ring lands probably broke) then I'm thinking run that super thick cometic gasket and swap the #1 piston out with the spare engine. I want to balance doing some level of upgrading if I open it up, and not snowballing into upgrading parts that I really don't need at this point. We'll see what tonight reveals!

As for the wastegate, an external would be nice, but I don't think there's a good effective spot I can place it without cutting up the inner fenders. The header came with a wastegate mounting flange and I had to cut it off and weld it shut since it was running into everything. If I can get the stock wastegate to work, it's a lot more low profile and I can still control it with an inline boost solenoid (I just picked one up, but need to get it making "minimum boost" first). If I can't get the stock wastegate to bypass enough air, then I'll definitely go to the external, but packaging and simplicity wise the stock one would be preferred.

 

I also just realized the target AFR ramps to 12.6, on the next tune I'll richen that out well into the 11s to help keep everything cool like we do on the Tundras. I was just running the default 2JZ target map. Not sure if that would've prevented the issue but it'll certainly help while I'm running the NA parts.

 

It's been a decade or so since I've messed with that turbo but back in my diesel hot rod days, when we would use that turbo as a top turbo in a compound twin setup, we would drill that wastegate open and weld in a bigger puck to help bypass more exhaust if we didn't want to do an external gate.

 

Late to this party. I just binged this entire thread.
You sir, are my people.
Fantastic work. That thing ticks all the boxes and it rips! Love it.

 

Pictures will tell the story. And if you want to think on this:

-Low compression
-Lots of blowby
-Leak down shows it through the crank
-Bore scope shows clean cylinders and intact piston

What am I?








Below was me being retarded and not realizing there were extra bolts holding the cam cover on. Luckily I have a whole engine of spare parts!













According to Car Care Nut this head gasket has blown 17,364 times









Confirmed, can only access the front three connecting rods. And to make matters worse, the only way to pull the "upper oil pan" is by removing bolts that go into the transmission---except I have an adapter plate to run a 350Z transmission (CD009) so those bolts can't even be access without removing the transmission entirely.





I can't believe these haven't been replaced:



And there we have it!











Funny enough, the first engine on my buggy had the same exact failure, and this piston will join one of the ones from the buggy as desktop memorabilia!




Path forward:

Engine is in great shape. I will pull a piston from the backup engine and swap it in. I already ordered the 2.4mm Cometic gasket and ARP head studs. I will drill out the turbo wastegate port so boost can come down to a normal level, and I will richen out the tune a bit. Otherwise she's going back together to party another day, and continue the original plan of building the spare engine for the future.

 

Damn you're ambitious and get shit done quick lol impressive. What kinda CR will that 2.4mm gasket net you? I vaguely remember that being a touch on the lower side when I did mine. I'm pretty sure I went with a 1.8mm and I calculated that to be 8.4-8.6, I think.

 

Drop it to 8, e85, and leave the waste gate alone.