DrAtomica

Short Update:

I test drove the car with my friend who has an advance scanner. We tried out many different combinations of "gears" on the ECU.
First off let's start with idle. If the car is in 'P' then the idle drops down to something that is more stable just like how it is in auto BUT if you take it out of 'P' it increases the idle by a slight amount as if the car is in drive and you were pressing on the brake. So what I'm thinking is that it uses a bit more gas if its not in P.

Now onto the driving part, there are 3 modes that we tried driving in. The purpose was to see how the ECU reacts, how the timing changes and if there any other inputs that are off.
We tried just in neutral and going wide open throttle under load, so about 0-80mph.
Then tried it in "L" and going wide open throttled under load.
Next up was "2" and going wide open throttle under load.
We tried do that 3 times for each mode so in total 9 pulls and the results were that there isn't really any difference in driving, the car feels about the same in all modes.
Some people have mentioned elsewhere that putting in "L" or "2" has better performance or response but I'm not sure, it didn't feel like that although I may be wrong.
Next up is the best news: VVT-i is working on ALL modes! Which means that on 98 SC400s and most likely 99 and 00 as well, it does not disable VVT-i.
The low end torque missing that I mentioned in my video was probably because my exhaust wasn't completely bolted on while I was doing testing back then.
Which means if I don't care about Check Engine Lights, the electrical stuff on the swap is pretty much done. I have wired in the NSS and the reverse switch.
On LS400s and GS400s I can see why it's an issue, however that being said I will still install the ATemu because if the car is neutral I can get better gas mileage if I'm at a stop sign or something.

Matt L

DrAtomica, this is great news! You just made my day. I am closing a deal on a 1998 SC400, Arizona car, rust free, diamond white pearl with 120K. I plan to drop it, get some nice rims and tires, get a KBD front lip, get a cat-back, then do the manual swap using your build thread. I am very happy that the VVTi is working. Can you tell me more about the ATEmu, where to get one and how to wire it up?

CLass of 1

Glad you found one Matt! I found some local but not the right color. Very cool!

DrAtomica, awesome news man! Thrilled for you! I think you’re paving the way for others in a major way. Congrats that you’ve got VVTi! Lol

Nick

KahnBB6

iTrader: (5)

Big news and findings in that post, DrAtomica!!! Excellent investigative work! I also feel you have now removed any guesswork for others to follow with their own 1UZ VVT-i manual swaps. I hope the ATEmu does end up giving it that final tweak to make it perfect!

DrAtomica

Been quite busy for the last few weeks but here are some of the updates with the car.

Starting with stopping, I upgraded the entire brake system with new calipers from a MKIV TT both front and rears, rotors, OEM pads and stainless steel lines from StopTech.
I drove the car with just the fronts for a few days, my old setup were LS400 calipers and there is a significant difference not just in brake pressure because of the lines but also stopping power has increased tremendously.
You can still find them online for a good price directly from Toyota for about $150 a caliper. I also want to mention that I have been reading online a decent amount of people using the TT calipers from O'reilys or some other store, those are rebuilt units, however, there are also units that have been casted but sold as rebuilt with no part number or manufacturer stamped onto them. Running rebuilt ones should not be much of an issue because rebuilt kits are fairly simple however running an entirely new casted ones with no information is something I'd strongly advise against. You don't know if those castings have been tested, what material they have been made with, if it was gravity or pressure casted and have no way to trace that information to it's roots so for your own safety I suggest do not buy those but rebuilt ones with SUMITOMO stamped onto them should be fine because its still the original casting. Some owners may report that they are working fine for them or had no issues but we don't know how they are driving and how long those calipers will last, saving $100-$200 is not worth wrecking your car or risking your life.
I also upgraded the rear calipers a few days ago so now my car has a full set of TT calipers and couldn't be more happier with the braking power, I'm used to a softer pedal so switching to stainless steel lines need me some getting used to.
I have tested from 60-0mph and 100-20mph, the braking force applied is more than sufficient to get you out of a quick mess.






A few other things that I will do and have done.

I upgraded the rear subframe mounts to solid bushings from Battle Version, the rear ends feels like it's one unit, the chassis and the subframe have no movement so you feel very confident when driving fast and especially when taking quick turns. There is a slight more clunk when I shift hard but it's not too noticeable, for myself I'm okay with it because it makes the car feel more sportier. As for the ride quality, I didn't really notice much of a difference in terms of feeling more vibrations or anything like that from the road. I'm guessing the other arms connected to the subframe are responsible for all the NVH. Worthwhile the upgrade in my opinion if you enjoy spirited driving.

I also painted my passenger seat black and so far it's holding up quite well, used the base and trim from a OEM black seat.
Preparation of that seat was to clean the entire seat first, remove all oils by using acetone and rubbing alcohol. Once the seat is completely dry, lightly sand it with some sandpaper. I used 400 grit because that's what I had at the same time but I think it's better to use lower grit, somewhere between 180-240. You do have to be careful the lower you go because you don't want the leather to rip, just scar on the surface. Clean the surface with rubbing alcohol and make sure all the dirt is gone, once that is done wipe the seat with acetone to allow the pores in the leather to open up and use a heat gun to do even more so. Right away start painting because the time window is not that wide, the first layer really needs to adhere inside the leather pores to ensure long term durability.
I also dyed the net behind the seat to give it a personal touch, I'm not a fan of making the entire interior black but do want it to have some highlights.
Finally had my front and rear bumpers painted since they took a decent amount of damage from many road trips, the rear bumper is from a Soarer and the license plate position is slightly different so need to figure out a way to mount it properly, currently it is just ziptied.

What's next?
I need to change my front endlinks, get poly bushings for the rear sway, do my inner/outer tie rods, do the valve cover gaskets and finally fix my power steering leak issue, I already have the main hose from DriftMotion but as of right now don't know if that will fix it or not because there may be other leaks.

DrAtomica

You can get the ATEmu from SerialNine or even quantumAuto, if you want directly from the source then all4swap is the way to go.
I haven't wired in mine yet so I can't give you a confirmed list on how to wire it up but I'm working on that so will update when its done.

Thanks Nick!!

Thanks! Yeah I'm hoping the ATEmu may make a few things smoother but so far it feels like any other manual car the way it starts up and drives, no fluctuations on idle or anything of the sort.

DrAtomica

Power Steering Fix

Decided to buy a power steering line from driftmotion to replace the stock one. Mine was leaking extremely badly and honestly it was leaking for many years. I never knew where to get a replacement line from because on RockAuto there was a mismatch on parts, online there was almost no aftermarket so I gave up. It seems in the last 2 years or so there have been more people making parts for the car so driftmotion and excessivemanufacturing do carry out these lines and I also read the ones from RockAuto will work even they show different part number for pre 98 and 98+ cars.

The one I got is a SC400 power steering that goes from the pump directly to the steering rack, installation was not too bad, had to remove the oil filter to get more access to it but other than it went fairly smooth.
No more leaks coming from the lines which is great because before it was bleeding fluid everywhere like a decapitated arm.
Adding this line WILL delete the power steering actuator that is connected by the two small hoses to the intake which is responsible for increasing RPM when you start turning but honestly I have not felt any difference, none whatsoever.

perfctreig

following up on this thread -

What are your RPMs at 60MPH? 80MPH? On my '93, I'm looking at various options for a manual swap and was wondering if the CD009 is worth it or if I should stick with a five-speed. The one thing I remember is the high RPMs on my manual MKIV VW Jetta. Granted that was a 1.9L engine but it ran about 3500 RPMs at 80 with a five-speed manual.

DrAtomica

60mph @ ~2000RPM
80mph @~2700RPM

Choosing your transmission depends on what you're going after, CD009 has well spaces gears so you never drop on power and can take a lot of abuse/power.
Also you have to remember that unlike a FWD you also have a differential gear, so take that into account. It's transmission gear + differential gear + rpm = speed.
98-00 SC400s have the lowest/longest differential gear ratio (3.266) so you can't get any lower RPM than that

perfctreig

Thank you! I found the thread on this where I discussed the RPMs on my 2000 Jetta vs. my 2006 Avalanche. I mentioned I was at 2600 RPMs at 75 MPH on the Jetta and at 1800 RPMs on the Avalanche. Much quieter!

KahnBB6

iTrader: (5)

Actually... there is in fact ONE more potential lower gear available than your stock 3.266. This would be ONLY the 2.917:1 ring and pinion taken from a 2007-2016 Lexus LS460 rear differential. This would require a full custom differential rebuild. It has not been tested yet but so far it has been theorized that this ring and pinion should be the same dimensions internally when compared to SC/Soarer/MKIV/GS diff internals.

I have looked into this myself a bit. See the thread post below on SupraForums and my conversation about it with SF member Wreckless:

https://www.supraforums.com/threads/...#post-13970396

...

As for 5-speed vs 6-speed I think it's a matter of preference and style. I have an R154 transmission and 3.769:1 final drive gearing and 275/40R-17 rear tires. At approximately 80mph I am spinning at 2,960rpm and at 60mph I am spinning at 2,240rpm. Other than when navigating a parking lot or driveway I never cruise in any gear below about 2,050-2,100 rpm with my 2JZGTE (in sequential boost mode) because below that point I would be lugging it.

In my 1999 LS400 with the same 4.0L 1UZ VVT-i V8, same 3.266 final drive ratio and A650E automatic that your SC400 came with I routinely see lower average city cruising rpms so I think you can do cruising rpms a bit differently than anyone who has a 3.0L JZ engine can.

I think the 6th gear is good to have and you already have the car set up with that CD009. With my car's drivetrain and transmission I theoretically could custom swap in a 3.615 ring and pinion from a 1989-1995(?) LS400's differential and go *slightly* lower... or I could swap in a 3.266 and go much too low with an R154's gearing... unless I had an extremely powerful engine build to make up for the then very long gearing.

But at that point depending on the power output an R154's ultimate limitations would need to be considered against a CD009 which is better suited to your range of gearing or against a T56 Magnum which is better suited to the 3.769, 3.916, 4.083 and 4.272 ratios with a strong leaning towards the latter two.

2700rpm at 80mph is not too bad. If the LS460's 2.917 ring and pinion were proven to work in our differential housings then I think you might have the perfect ratio for your V8 with that CD009 setup if you aren't already happy with the 3.266 final drive.

Calculators used:
http://www.apexgarage.com/tech/gear_ratios.shtml
https://tiresize.com/calculator/

DrAtomica

This is quite the news, even in theory this opens up many more options and sounds like it'd be very good for a high hp build.

I can get a spare GS300 diff and try to see if I can get a LS460 differential and compare them. I planned out to gut a differential anyways so I can install a LSD but this may allow me to look more into it before I even purchase a LSD.

Currently I'm very satisfied with the 3.266 and cd009 combination although a slightly lower final drive has got me curious. The car has enough torque that even punching it on sixth gear at 70mph pulls it well, now will that feeling be the same with a 2.917? Possibly.

I can see it being useful on long drives across state while going 80mph and have a low rpm for pure comfort and on the other hand if the engine was putting more power it'd still be pretty good.

Looking at the RPMs, currently I'm at about 2000RPM @60mph and with a 2.917 I'll be at 1820RPM.
So about a 200RPM difference in cruising which is not too much but will be slightly more quiet and possibly get better fuel economy.
I think realistically I may not feel a big difference but I think it's still worth it for long term goals with a CD009.

Imagine having a T56 with a 2.917, that must be really low for cruising. At 60mph you'd be at 1450RPM which is wild, I think that'd be a bit too low for a stock 1UZ.

I guess now I need to find a LS460 differential and start gutting the insides.

DrAtomica

Asked a friend at the dealership to get some detailed pictures of the diff from a LS460.
They look extremely close to the SC one so this can potentially work.
I'm picking up an engine for my Celica this weekend (7A-FE) so I'll get a diff too.

KahnBB6

iTrader: (5)

^^ Yes, as you can see it does open up some new options, just as does the '89-'95 or so early LS400's ring and pinion at 3.615:1.

You'll notice that the main difference between an SC diff and an LS460 diff is that there are no side carrier axles build in. In the LS460 the axle stubs are inserted externally. This means that you cannot drop an entire LS460 rear diff into an SC (but you can do this with some model years of the LS430 rear diffs). It is *only* the internals of the LS460 rear diff which are very likely the same dimensionally as the ones you'll find in an SC rear diff.

So really you need to tear apart an SC diff and an LS460 diff and just get down to the ring and pinion parts, compare each side by side and take some measurements. Wreckless @ SF hasn't gotten that far yet but he planned to. It is very likely they are the same internals aside from the side axle differences but no one has tried this investigation yet.

Also... if the LS460 ring and pinion are *proven* to be 100% compatible with an SC diff then that should also mean by extension that any core differential part (that the ring gear bolts around) found in an LS460 style rear diff casing would be compatible with an SC rear diff. But again... no one has been the guinea pig yet to test these hypotheses yet.

DrAtomica

Alternator Upgrade
Stock 100 amps to 130 amps

My power steering pumps leaks have finally killed the alternator after a good 6 years. Since I've been considering doing a turbo setup on my SC400 I thought about what happens if I remove my power steering pump and replace it with something else entirely. When I get closer to that project I will make more updates but for now..

I will need more amps in the future and maybe the stock alternator with it's 100 amps delivery may not be sufficient enough, luckily enough the LS430 alternator is 130amps, that's an extra 360 watts that I can add to my system without stressing it.
The issue however is..
The LS430 alternator has an extra bracket and that bracket as seen in the picture below will come in the way. Some users have suggested that you should just grind down that bracket and that does work however looking at the diagrams in detail it seems like Lexus added that extra bracket to limit the vibrations and make it sturdier.


Good news is that there isn't much to it to add that in your existing 1UZ, all you need is to get the extended stud and nut.. that's it.
The parts number are such for the stud and nut
90109-08298 - Stud
90080-17242 - Nut

Remove the second bottom stud which goes into the engine and replace it with that one, put the alternator and use that nut provided.
Everything is PLUG AND PLAY. Same connectors and the alternator cable is easier to access/disconnect as well.

What are the advantages of doing this? If you're upgrading electric systems in your car then this can be something to make up for that extra power usage.
It can be electric fans, bigger audio system, more lights, electric power steering pump *hint* *hint* and so on.