550hp 2JZ 1978 Hilux Build

She's coming along!

 

I saw this the other day and thought of this thread. It wasn't nearly as cool as yours, but I will say the school bus yellow could be your new thing.

 

Serious skills... coming from someone with a hacksaw and soldering iron!

 

Has Tarzan taken a ride in it since your updated rear end shenanigans?

 

He hasn't ridden in it since it got turbocharged in general, thing is (was?) way too loud with a 3.5" straight pipe for his little brain to handle. Hopefully the muffler thing quiets it down enough for him, but I doubt it...

Even naturally aspirated it was really loud for the dogs, I had to be pretty ginger on the throttle to not worry about it blowing their ears out. I could put a "large" muffler under it, but not a lot of room to play under there plus mufflers are so ugly (even if you can't see them )

 

Hahahaha that makes sense! I can see a Super Dave helmet and goggles in his future!

 

I was having issue with the suspension reaching full compression. This was as close to the bump stop as it would get with the springs installed:



(This is the passenger side, you can also see the misalignment that now exists between the LCA and the bent subframe and bump stop area.)

I also measured the front end again just to get an exact number, I took the crane scale and engine hoist and looped it around a stud to get an exact force on the hub.



I came up with a range of numbers for coilover spring rate, and today ordered a 750 lbf/in spring from summit. Next was to figure out why the front was bottoming out. First thing I did as a hail mary was to machine out the upper coil seat as far as I was willing to go, but that didn't fix the issue. I then took everything apart and ratchet strapped the suspension up and realized the shock is nearly rubbing on the stock coil mount.



This isn't the simplest thing to solve. The coilover springs are about the same diameter as that lip that is near the shock body, and the upper spring perch centers the spring on that lip---ie the spring is such a small diameter that you can't remove enough material from the upper spring perch to make the spring perch clear the shock, you would just end up with nothing there. The spring perch has to fundamentally be changed and offset the spring in the stock coil bucket to clear the shock. Lots of ways to do this, but nothing particularly elegant and no nice way to keep it indexed in the coil bucket to prevent it from spinning over time and then jamming up the shock body again.

My solution I decided to try? Using the stock spring! And specifically cutting it down (to nearly half its length) so that it can rest on the coilover lower spring perch and allow the ride height to be adjusted. Then the factory upper coil interface can still be used and nothing gets near the shock body! I cut the spring down, literally in half, cut two 1/4" plates out (could do one, but the stock spring is so big it completely overhangs the coilover spring perch, so I was worried about the plates bending), and then welded a little section of 3" exhaust tubing I had laying around which keeps the spring centered.



It's kind of janky, but it works beautifully! At the lowest setting the bump stop sits about an inch off, and you can push on the truck and fully bottom it out for the first time! I think this is the move! It does give some issue if I ever want to swap springs, but the ride height at the lowest setting is right where I want it, with an inch or so of preload it should be perfect! Once the summit springs show up they'll get turned around and sent back---and then I ended up ordering MORE springs, but this time for the rear. The rear springs are 125 lbf/in, and right now the truck is sitting around ~2.75-3.0" of up travel in the back. I'd like to get that number about a half inch lower but the rear springs already have zero preload on them. I ordered some 80 lbf/in springs which if my math is right (this time....) then that should let me lower the truck 1.5" more than it is now, so with an inch of preload should be around the rear ride height I want, which is with the tire just below the fender to match the front.

The front end solution is working out great, whether it works on the passenger side with that bent coil bucket remains to be seen tomorrow.

 

Passenger side shock I was worried about alignment in the coil bucket, from being tweaked it actually ended up lining up better!



I then did the same setup as the driver's side and adjusted the shocks and settled on this spot as rode height:



And she's on all fours and looking pretty bad!



The adjuster knobs on the shocks make a huge difference, on the lowest setting it's really squishy and bounces around before settling down. On the highest compression you can barely move the front, and highest rebound it slowly returns to ride height and doesn't overshoot at all. Out of 20 adjustments I left it at 5 on compression and 10 on rebound. Excited to play with the suspension setup, and it's nice it gets so soft since the rear is gonna need it!

 

Holy crap!! It's time to play with the asphalt with the Hilux again!! I'm glad the suspension fun came out perfect! Sounded like happy accidental progress! She looks way better on the ground then on your lift! Congrats!!

 

Thing sits so proper love it

 

New rear springs came in today, got those installed then did some alignment on the front and rear. The rear axle had to be scooted over half an inch or so, and on the front end the passenger toe was way out. Then onto some fabricating of things for the rear. First was a new fuel cell filler, the stock Aeromotive one is an absolute pile of shit and I'd be shocked if it had ANY sealing capability. Bought a 2" ID threaded bung and cap and cut out a new plate.



But the real goal was to get the rear tires to clear now that ride height was so low. I wanted to flare out the bedsides, but the first requirement was to stiffen the tail gate area so it wouldn't rotate as the bedsides got pushed out. I've been meaning to do this for a long time, literally one derpy bolt at the bottom was all that held the bedsides on, really the tailgate latching is what held them in place more than anything. I just wanted it fixed, so I cut out a bracket and welded it to the frame.



I then made the bedside "flare brackets", which is a tab on the cage, a tab on the bedside, and a piece of sheet metal (with a stiffener on the back side). These I would like to eventually be a cool billet piece, but for now this boring flat bar will work.





This flared the bedside out about 1.5" so it just overhangs the rear tires. There is about an inch of up travel before the tires start to pass the bedside, so this was going to be needed very fast to save everything. And the completed product rolled off the lift, at the correct ride height and fenders flared out:









The truck is looking so good! Lots of little things I had been putting off coming together while I wait for other parts. At this point I'm not sure what else to work on that's needed to drive it. The driveshaft guy apparently has been sick, I told him I'd be down the hill this weekend so we'll see if he ends up getting it built by then.

 

That looks great! When you said flare the bedsides, I thought you meant rolling the wheel arch, but your solution came out very nice! Can't wait to see how it handles with all the suspension upgrades and bracing, should be planted now.

 

I might use a roller on the front if the front tires hit too much, but the rear was easy since the actual bed is gone so the bedside isnt much more than a flat piece of sheet metal!

 

Finally got the driveshaft today!



For maybe the first time ever I had to work on the truck without the lift. Ironically having a low vehicle makes jacking it up easier since it makes such a big height difference hahaha



The FJ is currently hogging the lift





Everything went in smoothly, then we bled the brakes, clutch, and cooling system. I did find one small leak on a coolant tube so pulled it off and sealed it with the welder then ran another pass over that stretch, otherwise no issues! Right now it has straight water while checking for leaks. Bleeding the cooling system is quite a bitch, this time it took the thermostat opening like two or three times of getting bubbles out and spilling shit all over the floor.



And the whole time we were also trying to figure out why the laptop wasn't talking to the ECU, and turned out the cord was fucked and all but one of our cords laying in the house were just for charging and wouldn't transmit data (cheap pieces of shit). Finally we found a literal 3" long cord that would talk to the ECU to confirm everything was fine. Trip into town to grab a replacement, and then we took it for a test drive!



Everything seems to be working great! We only drove it a couple miles to warm up the rear end. I'm also very concerned about the front end alignment shifting since it's just held in place by friction of two M8s. My plan is to throw it on an alignment rack next week, see if there's any tweaking needed, and then do some fat tack welds to make sure the adjustment plates I made don't move. But the alignment actually felt really good surprisingly, I actually think the right side might have better overall alignment than the driver's side since it seems to have a bit less camber at ride height.

The shocks feel great, and we didn't notice the flat spots in the tires so I think they're good to keep running. The gearing wasn't as noticeable as I thought it'd be, though it's been awhile since I drove it. Going through the neighborhood felt like a comfortable 2nd gear instead of 3rd or 4th though so that's good. The resonator/muffler thing is hard to say if it did much, though at 2500rpm the truck is extremely quiet, and I think with the gearing I should be able to do interstate speeds in 6th around that rpm range, so if it can cruise in an rpm range that's quiet that would be a big win! The biggest issue is the rear fenders rub pretty bad, doesn't take much of a bump to hit the fenders. I think I'm going to grab a fender roller and try to flare them out a bit more, and then maybe add a second flare brace that's behind the axle. I can't imagine how bad they'd eat up going fast around a corner or launching it.

She's back and working great! Just a little bit of dialing before I start pushing it!

 

Got the truck aligned at a friend in town yesterday morning.



The camber was within 0.2deg between both sides, and the rear end thrust angle was at 0.50deg, I'd call that good enough for government work. The front right caster was at 3.6deg compared to the driver's side being at 0.1deg which apparently is factory spec. There's no way to (easily) fix the caster on the passenger side, either the caster is correct or the wheel base is correct since the upper arm/assembly is bent backwards, so the lower arm is exaggerated in how forward it is to get the wheel base in the right spot, and all of that gives it a lot (more) caster. I said to call it good and he just dialed in the toe and then adjusted one of the rear links to get the thrust angle to 0deg. After driving home I then added two big tac welds (ie an inch+ each) on the adjustment brackets I made. I was really nervous about the front end shifting and throwing the toe off and the truck darting off to the side, so now there are two welds and two bolts holding each pivot of the lower arm. I also tried to flare out the fenders a bit more with a tube, the rear I think moved a little but really I'll just need to add another bedside support since it's not stiff enough to bend by rolling it.

Today after working in the shop a bit, the wife and I went for a drive that turned into a 75 mile loop up into the mountains and grabbed some photos along the way.







The truck is doing fantastic! I don't think I touched the engine at all in the past few months, but it's still running great as ever. It makes so many turbo noises constantly and is a lot of fun, even at really low throttle you can hear the turbo spool up, the BOV is constantly dumping air, it's amazing how much more visceral all the noise is when you have minimal sound deadening hahaha. The exhaust has actually made a huge difference, from about 2300-2800rpm it's actually impressively quiet. Near 2000rpm and 3000rpm it really ramps up the noise, but there's a good rpm band without any resonance and accelerating from a stop it doesn't sound like you're trying to race everyone and everything now. I'm very happy with that tiny resonator.

The new gearing is awesome too, it doesn't feel like you constantly need to be shifting into the next gear. Cruising in 3rd or 4th feels great, and even in the neighborhood in 2nd feels good. With the stock diff if you were doing almost anything you wanted to be in 5th gear. Now in 6th gear at 2300rpm it's at 65mph, and 2700rpm is 75mph, so it should be able to cruise at interstate speeds and stay in that sweet spot of the exhaust not being crazy loud, and around 2900rpm should be 80mph where as before it was around 3500rpm so massive improvement. I'm still getting used to having to slip the clutch a lot more to get going.







The suspension is night and day different and is a huge improvement! The front end doesn't bounce all over the place hitting bumps or taking corners, and the whole truck is much more settled and controlled all the time. I set the rear to 5 clicks (out of 20+) compression and that helped reduce the body roll a bit and seems to be helping the rear fenders from rubbing as much on sideways bumps. Considering this thing has 2-3" of up travel, I couldn't feel us ever bottom out and even through bigger bumps honestly feels more plush than most if not everything else we own. For minimal screwing with the shocks I am blown away by how nice it rides considering how low it is now.

It's hard to say much about the 4 link yet, I am pretty timid at the moment to get on it much and haven't launched it since I want to get a couple heat cycles in the gears. I have no complaints about it, it feels planted and less rowdy I guess at first impressions. I want to get a camera on the back to see what it's doing once I start pushing it a bit more.

The flat spots on the rear tires aren't noticeable 99% of the time. Occasionally at a specific speed and smooth area you might feel them, but it's hard to distinguish that versus other noises and feelings going on. The rear tires are at 20psi so I think that makes a big difference since the contact squish patch is pretty huge that one little flat section just gets absorbed.

I am extremely happy with all the upgrades from this round of modifying. My hope is everything can stick together for awhile, and this can be a solid baseline to get the truck well dialed and reliable again. I want to take it easy and slow and get up to speed with what it wants so I don't shoot past a weak spot and destroy everything again. I want to drive it and enjoy it, and it's been a long time since I was able to get lots of miles on it!

 

I'm here for the light soot trail on the bedside behind the tailpipe.

 

It's kind of a vibe isn't it

 

It looks great!

 

Took the truck out for another 40 miles today and threw the GoPro on the back. My neighbor thinks I'm insane but new hardware always stresses me out from pushing it much. Even if it should be totally overbuilt, it's not like slapping on some product that's already been developed. Even though the links are huge, there could be bad welds, the geometry could be off, the handling could be shit, etc. I figured getting some footage of how the rear is behaving just to confirm it's doing what I think would be helpful and then I could start pushing it a bit more.

I threw some clips together of a walk around of the truck in it's current configuration and then a couple pulls.

https://www.youtube.com/watch?v=RrRi7_mWW08

I did not get a video of my last pull, but it was by far the best and I was starting to get confidence again to put the hammer down a bit, and I was able to get a 5.53 0-60mph time:



Certainly a LOT slower than I'd like the truck to eventually be, but between the start of the day and this last pull I had already dropped the 0-60 by over 0.5s, and now I'm less than a second off from my Tundra's 0-60 time which was done at a much lower altitude and cooler weather.

What is awesome with how the truck is currently setup is I can tune a lot of things without opening anything up. As you can see in the videos the suspension is twisting a lot from the torque roll, so I think I'll play with the shock settings since I now have compression and rebound adjustment on every corner, and can play with the preload if need be too. Additionally the boost control tuning needs a lot of work:



Ideally the boost curve would just hold at 33psi (absolute pressure, so ~20psi of boost) but you can see in the highlighted area the boost controller is fully opening the wastegate to try and bleed boost off, this is because I have it set in open loop control so it's completely based on that table in the bottom right. And how it's setup now is very conservative to not activate the overboost limits, but there's a lot of boost left on the table since that blue line would ideally be flat. And you can feel it, the truck accelerates and then feels like it hits a wall as you can tell boost is being turned down.

On my last pull (not in the video) I launched "well" compared to the other pulls, but it was lots of wheel spin occurring and the rear getting a bit sideways. Now that I have a rear end that can handle the power, I can activate the launch control and maybe be able to dial in the launch, though I think that will always be the limit. The truck accelerating as well as it is I think is somewhat impressive considering it's a complete battle of putting any power down in 1st gear. And of course, I have four levels of anti squat so could always adjust the rear links if I'm really feeling froggy. But at the end of the day, it is a 2500 lb truck with no weight in the back, and ultimately this isn't meant to be a drag racer. I think if I can get the boost control working nicely it'll be a bit more fun, but it's already a blast and I look forward to dialing in the current setup.

With that said, I do think the turbo is really holding it back. As you can see from the Dragy it's just not accelerating that hard, my Tundra's acceleration is around 0.5 Gs after it has gotten out of the holeshot and is tapering down, and the Hilux isn't getting over 0.5 G ever, which would kind of indicate a similar power to weight ratio I would think, and that would mean the Hilux is WAY low on power compared to what it could/should be. I think the turbo is just too small for big power---that's not necessarily a bad thing, because it's fun how fast it spools up---but in the future I think I will look at upgrading the turbo to something more suited for the 2JZ that maybe doesn't compromise the fast spool and can also not fall on its face as quickly.

Anyway, looping around to my opening statement, today I climbed a lot of steps in getting confident with the truck. I need to do more work to clearance the tires, but that seems to be the only real "problem". Oh and I filled up, and the truck is getting over 18mpg over the past two days! For some pulls and driving up the mountain with 5000ft of elevation gain yesterday, I am stoked, hilariously the truck continues to be the most fuel efficient thing we own!

 

That's awesome!

 

I think I could hear a little bit of passenger side tire rub on the third launch, but I didn't see any parts go sailing!

 

I think the fender braces need to be a half inch longer and then add another set behind the tire

 

Awesome update. Perhaps a certain @TurboKits member could perhaps have a conversation surrounding turbo sizing.

 

We used to run 62-67mm on the 2jz made great power and not crazy lag like the bigger frame 76s etc

 

The tech over the last few years has gone crazy. Heck, even the turbo I am running is nearly end of life (not end of support). The newcomer replacement is running a 68mm compressor wheel vs the 76mm I have. Price has doubled for that tech, but that's massive improvement in efficiency. This is only PTE, as well. HPT seems to be pushing even harder and has some impressive offerings and a great warranty. Regardless, cool time for turbos.

As a side note, XAT Racing is also SupraStore.com. I just recently learned of that after I stumbled upon this while researching something for myself.

https://www.motortrend.com/features/2jz-1972-chevrolet-el-camino

So, it appears there are a few vendors who can talk both the 3UR and 2JZ platforms, which is cool. Between experts on the platform, an expert in turbo technology (hint: Jesse may actually be receiving awards), and your own knowledge and skills, you've got all the resource anyone could ask for without even having to try to find them.

Looking forward to seeing where you take it next.

 

There's a number of engine side upgrades I want to do. I'd like to go to a DBW throttle body, the cable one works fine but the idle can drop really low before the ECU is able to correct it and sometimes it falls so low it then triggers the oil pressure cut off, so having more idle control would be nice. The intercooler also needs to be about twice as big and probably build a custom one for that. I'd also like to play with routing the BOV into the intake to try and keep the turbo spooled up. And then of course the turbo, looks like the HE351 I currently have is a 60-60, so definitely on the smaller end for the JZ. Maybe consider water meth, but the intake temps don't seem that bad even with the small intercooler so far.

 

Came across this little beast w/a well built 2JZ in it (just for inspiration of course), but I thought you might appreciate it...

https://bringatrailer.com/listing/1993-toyota-supra-168/

 

Thats a sweet setup! Though if I was getting a Supra I'd pass on that one, not a fan of the TH400 and I wonder if it has overheating issues with the filled block?

 

With a cage, parachute, and filled block, it's only meant to be driven a 1/4 mile at a time.

 

That’s a tragic thing they did to that Supra.