https://gmauthority.com/blog/2021/11...-on-the-table/

 

I was surprised at the wide disparity in quoted fully dressed engine weight numbers between all of the above engines. That’s why I take the 364lb figure with a grain of salt.

The engine weight numbers that I trust most are the ones I can see in someone’s video showing a fully dressed all stock example sans transmission being weighed off an engine crane arm.

No matter what, the 1UZ-FE in stock form is lighter than any JZ engine. And yes, the UZ series had a ridiculous amount of R&D put into it and did have heritage as a racing engine block design.

To Nick’s goals of creating something very unique since part of the way has already been paved for him I don’t think the 1GZ V12 will unbalance the car appreciably.

I’m rolling around in the heaviest stock JZ engine configuration with the heaviest Toyota manual transmission (the R154 being slightly heavier than a V160) and my SC is still quite balanced and controllable for its size with predictable handling.

Nick’s recently purchased coilovers should balance things out nicely but if not I am sure the manufacturer would be able to furnish him with some adjusted spring rates for the front and rear to compensate for the added weight of the 1GZ which is only 60lbs heavier (according to the data that I could find) than the 2JZ-GTE I have installed in my SC.

Even still, I suspect that there will be at least some slight weight loss from the V12 once he removes the stock intake parts and installs the custom 3D printed ones and ITBs. The billet oil pan should be slightly lighter than the stock one and I cannot imagine the external oil pump system will add very much weight on its own.

As a unique road car only I don’t think adding the V12 will be quite as critical as it would be if this were a track car intended for competition.

 

Yesterday I took a paint gauge to the car and verified that the hazy paint was only contaminated clear. I spent the evening compounding the car, but my foam pad didn’t remove all the swirls and other imperfections, so I’ve ordered a microfiber pad and will give it another go, soon. Here’s a couple photos after my detailing efforts:


In the morning light

Before

After


I have been trying to find the time to sit down and write out a response as well thought out as the ones you’ve provided GloriousSC, but I haven’t found that time. This will have to do…

First, I’d like to just say thank you for your thoughtfulness. You’ve given me some awesome topics to consider and pontificate! Before I respond to the points you’ve raised, I want to preface by repeating that I am NOT intending to ever take this car to the track with any sort of regularity. This is a street car, pure and simple. Now, do I want the car to handle like a pig? No. Do I want the car to accelerate like a Prius? No.

The weight difference from a UZ V8 and a GZ V12 is tangible, there’s no doubt. The way that weight is distributed is no doubt important, but with clever use or redistribution of that weight, perhaps the extra weight’s effect will be negated, somewhat.

Having said all that, if the weight and balance cause me to lose 3 seconds a lap at Road Atlanta, I don’t care. If I lose 0.15G of grip, I don’t care. What I gain is far more valuable to me than lap times or grip. What I gain is exclusivity, specialness and driving experience completely unique to virtually any other Lexus in the world.

So, for the moment, let’s put the weight to the side.

As for power, your response gives me more confidence that I can reach my goals, actually. Was the 1GZ-FE developed for high horsepower motorsports? No. It was engineered above all else to produce smooth power and large amount of torque. That being said, it is still a slightly over square engine. It’s not a long stroke diesel. As far as I’m concerned, the head will be the make or break, but the block will do what I want it to do.

You bring up an excellent point about the way the heads will flow being so vital. But, you made a point that early 90s heads don’t flow well, and you’re right, but this isn't an early 90s engine. In fact, the 1GZ intake manifold shares some design with the 3UZ-FE, as they’re both ACIS (acoustic control induction system) manifolds. They’re also both BEAMS engines. This isn’t an ancient engine. We’re not talking about a Jaguar V12 from the 70s that was used and reused for nearly 30 years.

But, let’s assume that the 1GZ-FE is only able to flow like a 1UZ, 125 CFM per cylinder. A 3UZ flows 235 CFM per cylinder, according to your data, which is 1,880 CFM total, compared to 1,500 CFM for the 1GZ. Now, that’s a 25% variance, which is no small number. But, like you mentioned with your post about the modded 1UZ making 533 horsepower with 1mm oversized valves — and other head and manifold mods I’m sure — but making 533 horsepower at 7500 RPM is extremely close to my stated power goals. They did that with 270 CFM per cylinder, right? I am fairly confident that with 12:1 compression, head porting, oversized valves and custom cams and all the other modifications I plan to make, that I could at least equal that 270 CFM flow rate. Even if I were only able to achieve 250 CFM per cylinder, that’s 3,000 CFM total, compared to the 2,160 CFM they achieved with that 1UZ you referenced, with 533 horsepower. That means this V12 build would flow about 40% more air and have 2.0:1 higher compression, how much power would that be worth? 50 horsepower? 100 horsepower?

If I made 600 horsepower on an engine dyno, like your 1UZ example I’m referencing here, I’ll be happy as hell. 7500 RPM is exactly where I want to be, too. Using a 2JZ as reference, being a square engine design, it comfortably revs above 7500 RPM with only slight valvetrain mods. So, I’m convinced I can achieve my goals here without needing to rev the nuts off the car. The 3UZ might be better overall, I am not, nor will I ever argue that the 1GZ-FE is the ideal engine. But, it has something no other Lexus engine can offer and I am determined to make this V12 work.

In other news, my coilovers arrived last week. They look really nice, hopefully they ride as good as they look! I do truly wish I had spoken with you boys before I placed my order because the Gixxer Drew stuff is really compelling. But, made to order and I’m stuck with this setup, for now. I’ll install them once I get my wheels, which are on a 12+ week back order. I will keep you guys posted.

Last, I just wanted to also clarify that I am not looking at LS400 brakes, I’m looking at LS460 brakes. Very different beasts. LS460 calipers, with a 14.2” IS-F rotor will slow the car down just fine. Of this, I am certain. As for fade, again, not a track car. If they’re able to slow the car from 120 MPH to cruising speed twice in the span of 30 seconds, that’s probably about as much fade resistance as they’ll ever need to exhibit.

Like I stated, I am building a road car. I am making conscious decisions which I know will negatively affect performance, but they’re with the big picture in mind. This goes back to my first post and using a car as a visionary model, constantly measuring against it, but having very clear design goals and driving characteristics in mind. Aston Martin know that 99% of their customers won’t see real track time. But, they fit a DBS with carbon ceramic brakes because for that 1% that do, the car has to stop consistently with zero fade. In this case though, I’m the designer and the user. I know what I’m gonna do with the car. There is no ambiguity here. And if I change my mind, I’ll change the build. No big deal.

Having said all that, I’m really appreciative for the thoughtful dialog and wish it to continue! This is what I aimed for in my initial phases here. I need to suss out a lot of potential pitfalls and problems now, to make everything go smoother later. Thank you guys for your contributions!

Nick

 

I agree.

Like you rightly point out, you have to view this build through my lens. A street-driven, comfortable, lens. The billion dollars of R&D invested in the UZ platform is not solely beneficial to it’s self alone. The GZ was first produced in 1997. It shares design elements with it’s UZ predecessor. Six bolt mains, forged crank, all the accessories are very similar in position and mounting and transmission bolt pattern is the same. I am of the opinion that this was not in an effort to cut costs — you’re developing a V12 for one single model afterall, so cutting costs goes out the window — but instead, a continuation of the development invested in the 1UZ-FE.

The application dictates the final design, i.e. a torque biased powerband on the GZ and a nearly square bore and stroke, but the technology and know how stems from the successful 1UZ. At least that’s my take on it.

Nick

 

Just an update on my work. Had some time this weekend, so I decided to get the ball rolling on my maintenance/revival on the SC. Saturday I did an oil change to my daily — a 2012 Camry — and did two to the SC.

I first pulled the drain plug and took a sample of the oil to send to Blackstone. They suggest to take a sample from the middle of the change, but I needed to preserve the oil level so I let a couple seconds of oil go and then collected my sample.

Next, I poured in Engine Flush by Liqui Moly. I peeked into the heads through the oil fill cap when I first got the car and saw a little bit of deposits, so I wanted to try to clean that up. In the fluid goes and after 15 minutes at idle, it was time to drain the oil. The previous owner used Dino oil (yuk) so I’m making the switch to synthetic.

But, I wanted to make sure I got out as much of the Flush and old oil as possible, so I filled up with 0w20 — cheapest I could find at Walmart, called Supertech — and idled the car for another 15 minutes, with a couple 30 second intervals revved to 2,000 RPM, and a couple quick little 4,000 RPM revs, to make sure it was circulating everywhere. The logic with the 0w20 is that it would get into every little nook and cranny for the purposes of flushing the engine. Wear was not a concern for a super short interval/light load operation like I was doing.

After the 15 minutes, I drained that off and replaced the Fram filter I had just put on there for 15 minutes, with Liqui Moly 5w30 Top Tec 4200 synthetic and an OE Toyota filter. This was recommended to me after consultation with Liqui Moly themselves. Side note: it’s very annoying where Toyota decided to place that oil filter. It’s impossible to not make a mess with those power steering lines in the way! Not to mention the undercover, but I digress…

After the oil change, I drained the ATF and filled with, you guessed it, Liqui Moly. I used their recommended Toyota Type IV replacement; they call it 1200. Two, 1 liter bottles just about did it.

While I was down there, I also replaced the transmission mount. Every time I shifted into gear the car would lurch and make a loud clunking sound. After replacing the mount, it’s definitely been lessened, but it’s still there. I hear the diff kind of go ‘thump’.

While I was down there, I cleaned up as much of the two pans as possible, both of which were caked in oil. I know the car has a power steering leak, but it must have been leaking for years, or it’s also got an oil pan leak. We’ll see. For the time being, I added Liqui Moly power steering stop leak to the reservoir. Worth a shot.

Now for the big stuff…I decided Sunday would be a good day to knock out the plugs, wires and coils. I bought everything from Rock Auto; Denso wires and plugs (iridium) and NGK coils. I read about the job and it seemed easy enough. Not so. The driver’s side ignition coil is a nightmare. Doesn’t help that I am blind and couldn’t find the second bolt for the bracket, but nevermind. I ended up stripping one of the screw heads and created a whole lot more work for myself, but hey, that’s why I’m an amateur.

In the end, I got it all done…TODAY… hours and hours invested in it. Along the way I cleaned up every part I came into contact with. I’m convinced I’ve reduced the weight of the car by at least a pound, with all the dust, grease and grime I’ve removed.

While the intake was off I also cleaned the throttle body and the MAF.

I noticed when I first got the car that revving in neutral produced a shutter and vibration on deceleration which to me smacked of a misfire. After the work today, vibration is gone and she purrs like a kitten. Pleased with the outcome but it was very tedious and back breaking work, hunched over the car like I was.

Im realizing just how out of practice I am. I haven’t done serious car work since my RX7 a few years back and it showed. I’m getting back in the swing though. Best part is, despite it taking two days, probably about 10 hours total, I had no leftover bolts! Cheers to that!

I’m too ADD to take photos throughout the process so I’ll just show you a plain Jane engine bay photo when j was finished:



Nick

 

Nick,

That is one very clean engine bay!! Nice work!

I too have used Blackstone at various times and they're a truly amazing analysis company. I hope you will get healthy stats for your 1UZ after they've had a chance to run the sample through. Liqui Moly is a new oil band to me. How did you come to learn about it? I'm curious as to how available this brand of synthetic oil is and what their recommended use of it is with 1JZ and 2JZ turbo engines. I have stuck with Mobil1 10W-30 synthetic at short 2000-2500 mile intervals for my car.

A note about your MAF sensor... I highly recommend NEVER cleaning it ever again. Since you have a newer 1UZ that uses a modern air meter unit and not a Karman-Vortex MAF as with the earliest SC400's it should be okay since you said the sputtering cleared up but be forewarned that cleaning these can result in a MAF failure. At least with the earlier big and clunky looking KV MAF cars it does. They can be pricey to find used and brand new they are extremely expensive to buy from Lexus.

I hope you find that the remainder of your transmission shifting clunk has gone away with the oil change! Some drive time with that beauty is in order soon!

 

Thanks Craig. The low lighting conditions help it look cleaner than it actually is! I did a quick once over detail when I first got the car, but she needs a TON more work to clean up to my standards. We’ll see when I get the time for that. I’m planning a full underbody detail as well, but I’m still researching which products will work best for my needs. I’d like to also find a shop to rent a lift and not have to lie on my back and get drenched and covered in oil and grime.

As for the MAF, I cleaned it and THEN read the can and it said specifically not to use it with the vortex MAF. You don’t seem to think I have a vortex one but I think I do. It looks like a turbine engine with the little element recessed inside the center portion. I was very nervous it would damage it but the car seems to be running fine. Not sure why it would damage it, but I took the MAF completely off the car and sprayed in ventilated area and moved it around to allow it to evaporate quickly. I’m assuming that design allows the cleaner to pool up in certain areas or something? Not really sure.

As for Liqui Moly, I can’t be sure where I learned about them, but I grew up around cars. My parents owned a garage that I later owned for a short time, and I suppose I just came across the name over time. I know they’re of extreme quality and very common-place in the Euro scene. I decided on them because they have a full compliment of additives. I’m using their Jectron fuel injector cleaner right now in two of my cars. They make all kinds of stuff.

Another interesting bit about Liqui Moly is that they have all of their additives in separate containers and you add as you see fit. For example, I added their MoS2 anti-friction additive in it’s recommended amount (50mL per L of oil) but with the Engine Saver high mileage treatment (helps prevent leaks high mileage additive like many common brands) I only added half the recommended amount cause I’m not aware of any oil leaks for sure. I suspect I may have one, but none verified. I’m still cleaning down the engine to then find out where the culprit is. By adding half, I’m not using an additive that I may not actually need or benefit from. I’ve also got the other half of the bottle left over, so I can add it to another car of mine or maybe to the Lexus if I notice a leak for sure.

Not world altering stuff, but it gives you control over what you’re putting in your engine. It’s more expensive and adds more steps but there’s benefits.

Nick

 

I nearly unsubscribed just for the satisfaction of subscribing again. Loving the car and the plans!

 

Haha thanks man. I’ll hopefully update soon with a second paint correction. My foam pads weren’t cutting it — no pun intended — so the microfiber pads I bought should get me where I need to go. I am eager to try it soon! My hope is that I can refine the finish to the point where the paint is almost flawless. It’s a driver car though, so perfection will never truly be possible but, I think I can get close!

Nick

 

Well, I finally got around to the paint correction. Compounded with microfiber pads this time and it removed defects nicely without taking off too much clear. I’ve come to the conclusion that the RSP paint is very hard. It took considerable effort in certain spots and after testing with my paint gauge, barely removed clear. I am still averaging about 4.5-6 mils thick all over the car.

A few pictures for you guys:

Washed, right after purchase


After compounding with microfiber pad


This was after the compounding stage, before polishing. Lots of depth and clarity!

After that I polished and then ceramic coated with Avalon King’s Armor Shield IX ceramic. I used it on all painted surfaces and the black plastics like the windshield cowl. Huge difference there! But I didn’t take before/after shots.

After curing for 48 hours, I took her out this morning and went on our first ever Sunday morning cruise with my wife and daughter! Really was a fun experience and something I could never have done with my old RX-7! My wife is pregnant and her back was aching a bit so I turned on the heated seat; much better, she remarked. Wife buy in is huge and I’m finally getting it with this car lol

Anyway, I’ve got my wheel parts and tires coming in very soon. The coilovers were delivered to me over a month ago but I’ve just been sitting on them till the wheels came. In the next few weeks I plan to replace the two front LCA’s with used Lexus originals with good ball joints (already bought), build the wheels, mount the tires, install the coilovers and lower it to a ride height I’m happy with. It should transform the car. I’m really excited!

For now though, I’ll leave you guys with a few finished shots of the car, including my detailed engine bay.

Nick

 

The color is awesome! Kinda wish I had that color. Maybe for my '93. Just took my '16 Malibu in for some work at a dealership (under warranty.). The Service Manager was shocked when my son rolled up in my SC400 to pick me up. He started gushing over the UZ engines, as he owned a LS400, an LS439 and has a Seqoia Can't wait to see this progress.

 

Yeh! I know what you mean. Went to a tire dealer just now and I guess it was a manager and came out personally and was literally beside himself about the car. I was looking to get a new set of what I have for spring driving season. He wound up doing me a lot of little favors.
All the time everywhere🤷‍♂️

 

Yeh a compound, polish and ceramic is probably the ultimate. Nice and deep tone to the color
I think Thomas or gerrb asked if your rsp car was seen here in the club before. I remember that car years ago showed up in a nice professional like photo. Had a good background, night or dusk, w excellent lighting that showed up the car very well and have not seen the car since

 

The car is looking really nice, Nick! Your careful paint correction and polishing really did make a big difference! It really is a special find in the Royal Sapphire Pearl! Yours looks close to new as it sits!

 

The previous owner had it since 2010 if I remember correct. He’s in his 60’s now, so he would have been in his 50’s for most of his ownership. I believe he was an enthusiast, but I’m not sure if he had a profile on CL. I’d love to maybe learn what his handle was if indeed this car has been on the boards previously.

This was a California car from new, till 2010, then it was a Washington car. Oregon, Washington is where he lives now and where I had it shipped from (3,000 miles) to me in Orlando, Florida.

Thanks Kahn! I appreciate the compliments and I’m itching to get my wheels put on so people don’t assume there’s a retired foot surgeon driving it lol

I made a new thread in the SC forum trying to seek help for an issue I’m having with my driver’s seat. It won’t go down. It goes up, but won’t drop back down. Is there a way to wind that seat down that you guys are aware of? My head touches the roof and it’s kind of uncomfortable!

Nick