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As I have stated I will be using the Mercury 2 TCU from Spitronics to run the A650E. The extra gear does help but how is what I was interested in. Im gonna explain it all in the next post on why I wanted to try this 5 speed auto and not a 5 speed manual swap.
Please watch this youtube video from engineering explained and you will see what I am getting at. The concept is to pick the correct rpm shift point BASED ON YOUR ENGINES TORQUE so that you will have the best acceleration possible. What I decided to do is calculate what would be the best shift points with these following transmissions.It is to see if they have nicely stacked gears to setup a good entry rpm in the next gear to keep the car accelerating well. I did all of the long and hard math work that took hours but unless someone wants to see all the numbers I will post them up later but for now we will stick to the results at hand. The engine torque numbers came from a dyno from a STOCK sc400 with the A340E (wanted to compare it with stock power to keep it simple). I took the wheel power and added back 22% for the automatic drivetrain loss (to get estimated crank power) to give me numbers to start, then I went from there to calculate shift points using 22% drivetrain loss on the autos and 15% drivetrain loss on the manuals. As you see the torque stays pretty good between 4000rpm to 4500rpm but drops off dramatically so revving the engine out to 6500rpm is wasting you time. Peak horsepower is 5600 so getting to far away from that rpm is bad yet again.
I could sit here all day comparing but I will just make highlights. The A650E range for rpm is from 4000 rpm to 6200rpm and its pretty consistent (note how it always lands in peak torque range in entry rpm).
The A340E takes the cake of pure ****. From 1st to 2nd is a perfect example. You leave 1st at 6500rpm to enter in 2nd at 3500rpm. You have to rev out the engine so far to then end up right under peak torque (remember this is the best calculated acceleration. shift any sooner and you enter too low in 2nd gear). At this point you spend a lot of time out of peak torque which is from 4500rpm to 6500rpm in 1st gear then 3500rpm to 4000rpm in 2nd gear. That is a consecutive 2500 rpm that you are revving out of peak torque.
The W58 and the R154 both have to be revved out completely in first gear to land in a good rpm range which I guess is okay (still a downside). Personally I feel that revving to 6000 rpm or even 6200 rpm (not an rpm more) would be okay but cutting the gears short means accelerating for shorter periods of time and thats what the manuals flaws are. If you see on the W58 and the R154 leaving 3rd and 4th gear early (5600-5700 rpm) is a must to enter the next gear at a decent rpm but the rpms in the next gears are sort of high middle point of the torque (sacrificing time you could be accelerating to have torque to accelerate in the net gear). Not exactly terrible but not as nicely stacked.
The A761E was just an idea to be thrown around for an alternative for a 6 speed but I will leave the judgments up to you on this one. I choose not to do a V160 do to price.
Feel free to look and make your own judgement on what you think is acceptable but this was a crucial part of my decision before I decided to take on this project.
Please take note of a few things:
1) this calculation is specifically for the 1uzfe engine and shift points based off the engines stock torque.
2) this is a stock to stock comparison between all the trannys with their stock parts (especially considering the stock torque converter stalls).
3) the A340E is not a bad transmission. With a modified torque converter with a higher stall and lock-up function that can stay locked up under power you will gain your mph back in the quarter while having great torque multiplication at the launch.
4) there is less rotating mass and less overall mass on the manuals which is the disadvantage of the automatics.
FINALLY THE A650E IS IN THE CAR. Here are the pics of the car with the A650E installed perfectly.
Before the pics this is the list of parts that made it happen and that are 100% confirmed to work:
- A650E from newer V8 vehicles (1UZFE VVTI)
- Stock 1UZFE (non vvti) flexplate paired with the A650E torque converter.
- Stock A340E transmission mount
- Stock transmission lines from A340E
- The transmission linkage for shifting is the same on A340E and A650E
- Front half shaft of 98-00 Sc400 paired with Rear 92-97 half shaft.
- Stock Center support bearing for driveshaft (92-00 is the same.
I have not included the electrical because I have not done it yet but I will show pics of where and how I ran the wires but for now enjoy these few pics.
Diveshaft issue solved Linkage lands in the right spot and shifts the tranny perfectly Stock lines from A340E and they bolt back in the same place Tranny perfectly mated to the engine. Proof that this is a A650E, it says 35-50LS
Today I went to the junkyard with the intentions of getting another external harness for the A650E because I was missing the connector for the Park Neutral position switch but it turns out the there are at minimum three park/neutral position switches. While I have encountered 2 with 9 pins, I have seen wiring diagrams showing 10 pins and all the pins are arranged in a different orders. They all still will bolt on all A650E no problem just remember to keep the locking washer for the nut that holds the position switch where the shaft comes out becasue those are specific to the switch.
Other important news is that I decided to grab more than I needed to see what parts are interchangeable: flex disc, torque converter (keep in mind that the doner car from the junkyard was a gs300 from 98).
I took the gs300 torque converter and decided to try it out on the v8 A650E and it slaps right in no problem. I would assume that the 2jz has a higher stall on the torque converter but that is speculation. Where it gets interesting is when I tried out the flex disc. THE OUTPUT SHAFT FLANGE ON THE 98 GS300 USES THE SMALLER FLANGE BOLT PATTERN WITH THE SMALLER FLEX DISC. I want to stress this because If I would of gotten a Gs300 transmission from 98-2000 I would not of had this driveshaft issue. Meaning at the end of the day that I could of used my stock driveshaft and just swapped the bell housings. So good news is that the cost of the swap is lower than what I had claimed due to the shaft issue which was an issue that could of been avoided. I forgot to bring my 30mm socket so I could not take the flange off and measure the width of the splined section on the output shaft. If I had to guess this section of the output shaft is the same size as the A340E that I measured. On a small side note the 98 sc400 flex disc weight (larger bolt pattern) vs 98 gs300 weight (smaller bolt pattern, same as A340E) is pretty noticeable but what strikes me odd is that the smaller ones are heavier. I have three large flex disc and three small ones and the smaller ones are consistently heavier. Dont know what this means but I thought it was interesting.
Went ahead and grabbed all spare A650E solenoids while I could from doner car (98 gs300) As you see from the red mark I got this from the junk yard from the gs300. Smaller flex disc bolt pattern and its the small bolt pattern shared with the A340E. GS300 torque converter grabbed from the junkyard to test fit on v8 a650e. slides in no issues
So I have been working on putting the TCU in the car and now it is. I felt I should stop and show some in the process pics and also me testing out the connections and the display. Details of pics at will be under the picture.
Was debating on putting the TCU on the floor next to the ECU but I didnt want the passenger to be kicking the unit. As far as I know this is the best place to put it.
Im running the wires behind the dashboard/radio/ac control module. Since there is really no good place in the middle of the car to send wires to the Transmission I will be poking a hole in the transmission tunnel to feed the harness right on top of the transmission. Will be using a grommet and wire loom is tight in the grommet so hopefully no leaks.
Different view to see where the wires are going.
The green and yellow wires are for the TPS IN and RPM IN. The other wires with the blue top at the top are the wires that need power form the fuse box. That is what im currently working on.
As you see this is the given info that is shown on the display; What just testing it out prior to putting the TCU in the glove box to insure everything is working. This is one of 3 screens. Screen number 2
Screen number 3
Me testing the the TCU, Testing the Display and uploading the A650E tune into the TCU.
Well these converters that I'm showing are specifically off of A650E transmission. A650E and A340E converters have the exact same dimensions but use a different spline because the splines are not the same on the transmission. But you are correct about the 2jzgte torque converter. Bigger bell housing and bigger converter for sure and a few other goodies. The 2jzgte got the 30-40ls and the others got the 30-40le (both being a340e transmissions). If anyone has photos to show specifically how much bigger and pictures and general that would be awesome
So here is an update on the build. I have been spending a lot of time and care on the wiring and properly running wires to make sure that when the vehicle is moving that I do not have a failure due to bad wiring and/or something coming loose. It really made me realize that to do the job correctly it takes a lot of hours.
So I ran power wires to where they needed to go but I did notice that the diagram does not clarify if a relay for every power wire is required. I contacted one Spitronics dealer and he said it is highly recommended that realys be used. Having consistent power going to the TCU while it is not in use could harm the unit. So I got to work on a relay board to run power to the TCU. I do advise using all of the available tabs that are unused in both fuse boxes of the vehicle (one under the hood and one on the inside next to your left foot). Please check as some of the tabs have constant power and some are already running through the main relay.
Always test for continuity after every connection to insure the best quality job (also tug on the wires to see if it comes apart and if it does, well, you just made a ****). Im am going to show what tabs I used to make it easy on you guys.
So whats hooked up? All of the power wires are hooked up and the negatives for the TCU and the Relays. Now when I turn the key the unit turns on and the display powers up with the tcu.
Whats next? Next things on the list is hooking up the wires on the steering wheel and hooking up the wires to recieve the TPS voltage also well as the RPM signal. The steering wheel I am not to concerned about but it is going to be tricking tapping into the tps signal (concerned with issues of voltage drop) as well as getting the RPM signal. Those I will be getting into later when I go to wire them and will make a specific post just for them.
Enjoy the pics.
Here is where I stared the relay board. As you see there are two negative wires. I wanted to make sure I had a good ground. The relays are only Velcroed to the boars so that way it is easy to take off if one were to go bad. Wires are coming from the floor up across the transmission tunnel to the other side to get to the glove box. If you are are wondering how the wires are coming from the fuse box to inside the car here you go. You have to remove the front left tire and the linder and you have a hole where wires are already running. you have to rip the grommet open a little but I promise it wont leak. I have been running my transmission cooler fan signal power through this same place, This is where I hooked up the relay board. Held up via screws. I put it here so that is anything goes wrong with the relays I can reach it. This is slightly higher than the carpet but enough to where it is not seen. more ground wires = less potential problems. Here also is the two ground wire connections for the TCU. I extended the short wire it had and ran 8 gauged wire to ensure a good ground so the TCU would not fry. The bottom two tabs are pretty big and they have constant power even when car is off. The two wires up top are connected to where the rear defogger use to go. When my tint was done is messed up my rear defogger. The one on the right has consitant power but the one on the left has power only when the ignition is on. The wires are running under this plastic piece and as you see exiting out to the right.
I forgot to upload these three pics. As you see the tcu is now permanently in the glove box and the display is working according. The next few post is going to be about how I am going to run the buttons through the wheel clockspring. while I am at it I will also provide the wiring diagram for the a650e from spitronics. someone reminded me that I havent uploaded it yet.
All of the positive and negative wires are hooked up for the TCU and all of the power wires are already run to where they need to go. This is turn key power and as you see the Display is working perfectly. Im gonna get a closer picture next time. The stock wheel clock on my lexus has a total of 8 available lanes if you include the two wires that are for the air bag (this sc400 came with the phone option so it has extra electrical lanes for that). No I did not loose cruise control (im expecting it to still work even though the transmission will be disconnected. hopefully it will). That uses three lanes. The buttons are gonna use three and the horn uses one making use of 7 lanes. this is the clip on the back of the wheel clock on the other side. unfortunately the colors are not consistent on both sides so test for continuity to ensure that the wires you hook up are where you want them to be.
Steering wheel pics here they are! I have hooked up the buttons for the up and down shifter on the sterring wheel. As an extra I decided to work a little on shielding the wires that are sending the signals to the TCU. On the harness this is shielded wiring for these wires already provided by Spitronics so I figured this was them telling me that the wires should be shielded the best than can. Since I play guitar I am very familiar with radio signal interference ****ing up your guitar sound so I used copper conductive tape on the inside of the guitars. Since I still had some left I decided to shield the wires as best as I could and where I could. Keep in mind I put some on the back of the wheel clock spring but forgot to take a picture of it. I dont know how necessary this was to do but I guess you can call this overkill to the max but as long as this eliminates potential problem, I'll be happy and the quality will be better.
FYI: The conductive tape is not something you can buy anywhere if you plan on doing it as well. Keep in mind that even the adhesive on the tape will conduct electricity! be sure to make sure the tape is grounded to the chasis please. Aluminum conductive tape will also work. Both copper and aluminum are the best when it comes to blocking out radio frequencies.
On the back of the steering wheel. on the back of the airbag side. These are the three wires that are going to the tcu. If you follow the wire to where it has the grey covering that is where it is already shielded. Just be sure to ground the extra bare wire that is in there because that is responsible for the shielding. a wider view
So long story short all of the wiring is done on the car and this weekend coming up the tranny will be going in. The last thing I will do is test all connections and wires then I will start the car. hopefully everything goes good. here are some pics.
IT IS DONE. I HAVE SUCCESSFULLY INSTALLED ALL OF THE COMPONENTS AND DRIVEN THE CAR WITH THE A650E.
8 months ago this was just a thought but I have made it happen. I have a few pics now to show. One of them is a a super rare carbon fiber stock spoiler that I paid handsomely for. Vids, pics, ride alongs, new drag times are gonna be up very soon to see if the difference is really worth it. ending cost for me ended up being right under $1200 and the difference is noticeable.
Things I will start to get into: more specifics on tuning, dealing with a few issues the a650e has, diff gearing, pros and cons that I quickly found. all are coming soon.
As you see this looks exactly like the stock spoiler but just in carnbon fiber. will get close up pics later. This is the first night of driving and tuning the transmission which was 2 nights ago. This is how the graphs for the solenoids started but looks very different now.
This was really awesome to read, I was actually trying to decide between the Spitronics TCU and the Dicktator TCU, I think I might just try both to see which one is better/easier.
So It has been a while since I have posted on this thread and I fond it funny that this thread has like 3500 views currently. It is unfortunate that I have to say this but I drove the car for 3 months on this setup and a week after I completing this swap I had decided that I am yanking it out and doing a 5 speed manual. I spent those three plus months trying to see if I can make the setup better but there was no success for one major reason. I am going to do another full right up on this thread to continue where I left off. LONG STORY SHORT, DO NOT FOLLOW IN MY FOOT STEPS BECAUSE YOU WILL BE DISAPPOINTED! Yesterday I finished my r154 swap into my 92 sc400 and the amount of performance that was left on the table with the a650e is almost disrespectful.
Stay tuned for my full right up (again) and review of the spitronics Mercury 2 tcu.
So for the almost 4000 people who have viewed this you are wondering what went wrong and that is what we are here to discuss. I am going to break this up as best as I can.
Natural Flaws of The A650E: To start off the A650E is over complicated from the get go. I have seen both A340E and A650E side by side and the casing is exactly the same. Toyota decided to cram more components into the same box. Therefore brings the second downside of the 5 speed auto box, more weight. It weighs 30-40 lbs more (this is without fluid or converter). The third is that it is now more complicated to control. To shift into second gear I had to manipulate the shift solenoids (1, 2 are the 2nd gear solenoid position but solenoid three has to be blipped for 1 second and the lock up solenoid has to be active to bleed off some pressure to make it just right). To adjust 2nd gear harness you have to adjust the lock up solenoid pressure on the TCU. All this for just second gear. If I remember correctly, to adjust harness to get out of 2nd into third you have to play around with line pressure (which I really don't like because if you lower the pressure it meant you have a risk of burning the clutches overall and in between shifting). This tranny also has problems with being laggy which means a shift kit would help but it already shifts rough as F*** with lag imagine if you amped up the speed and harshness (kill me now). Also to install this this tranny to the stock diff on my car I had to get a 98-00 front half of a driveshaft and 92-97 rear half. Lexus decided to increase the size of the bolt pattern for the flex disc so thats the reason for the mashup. Do you know how hard it was finding the front half of the 98-00 driveshaft? I ended up buying the whole shaft. Note that A340E and A650E torque converters are not interchangeable because of different splines so you have to buy the torque converter with it. The 2jz A650E converter will go onthe the transmission but will not bolt up to the flexplate on the v8 and the v8 torque converter is thicker and goes into the crankshaft more. Im pretty sure you could use the 2jz converter if you wanted to but you would have to use the matching flexplate and since it smaller and rated for a higher stall it would be the cheapest way to get a higher stall............................what am I saying? Don't bother. Forget my bright ideas.
Real quick the way you shift gears in the A340E is by changing the sequence of two shift solenoids. There is no extra adjustment, line pressure and clutch hydraulic pressure can stay high and you feed it the gears with the shift solenoids and thats it; simple, awesome, fast.
Flaws of the Spitronics Mercury 2 TCU: I could be here all day telling every little flaw but I'll just get straight to the points. Its hard to get support since these people are in South Africa. The processing power of these units to me was underwhelming. I got it to work okay but your tune better be super easy and not complex. It can get complex at low speeds so what I did was have the shift points far away so that the engine reved out and had a specific zone to shift. Same thing on the downshifts. Sometimes it would not register that you made a full stop and it wouldn't go to 1st but when you start moving in traffic it would realize you are driving away from a dead stop and shift from 2nd to 1st (I was pulling off in 2nd) then scream up the rpm then shift harsh as F*** into 2nd. Second thing about the unit is that when you told the TCU you wanted full manual mode if you took off from a light in first it would shift into second and third gear then not shift anymore. Found out that is you have the shift points setup for full auto then switch to manual, it would still shift on its own. Then whats the point of full manual? Third thing is that all of the pressure solenoids went off of TPS. Very bad thing. The only way this tranny will engine break is when you have the shift lever in the physical position of the gear you are in but I could never get it to work. I asked for help and these people told me to up the pressure on the clutch hydraulic and line pressure solenoids (keep in mind my neck was already snapping from hard shifts and roasting the tires all the way up to 4th gear) and I wasn't going to do that. So what would happen was when i was in 1st, 2nd or 3rd and I let off the gas the rpm would drop and the drivetrain would be disconnected. I tried this with the lever in different positions but the same S***. I know for a fact the stock TCU does not have this problem but I think a combination of poor design, lack of thought process for the control of this specific tranny and lack of computing power is what makes this TCU suck hard. I do have an idea on how to fix all of these problems but thats for another post.
So why go manual? At this point the $3000+ is super worth it. I spent $1200 on the 5 speed auto setup and it went straight to the trash and I cannot find a buyer for this tranny or any other part I used.
Pros: Less weight, less drivetrain loss which means power gained, less rotating mass, more direct feel (especially with one piece driveshaft), if you want to do road racing or drifting this is the only route, less complexity, increase in gas mileage. I REPEAT DO NOT MESS WITH THE A650E UNLESS IT CAME STOCK IN YOUR CAR AND YOU HAVE THE STOCK ECU/TCU TO PROPERLY CONTROL IT. There is still no good controllers on the market for this tranny.
SIDE NOTE: Although I am not going to mess around with the A650E I will be messing around with the A340E that I took out of the car to build it and use a proper tranny controller to make another SC400 into a drag car. ATF SPEED makes a very good fully built A340E and the Baltic Supra is proof doing 200mph in the 1/2 mile. After the A340E then I plan on moving onto the the A761E and see what that can do.
It was a good read and lots of detailed info so thanks for that. Glad you decided to go 5 speed, the only thing better is a 6 speed
look into the ar5 from the solstice if you want a newer box, with all the work you did on the auto that should be no problem.
04-28-17, 01:25 PM
