Turbo IS300 5MT and Stock GE!
cool!
07-30-13, 10:58 AM
#78
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TRD diff installed!
So I haven't been posting my updates here in some time... I still don't know why my pictures come out so small... but ya...
Finally got around to doing this... I picked up a used complete auto LSD carrier from the wreckers and swapped in my TRD unit. In the end after thinking about it long and hard I went with the 3.91 auto ratio instead of the 4.3. Reason being mostly for highway cruising and not wanting the RPM's to be so high to just cruise normally. So far I'm happy with the setup - did my figure 8's break-in and just changed the fluid again last night after that. I have my stock 3.7 LSD carrier now as a complete spare.
Unfortunately I don't have pics of the actual TRD unit being installed as I was on vacation during that time and my buddy went ahead with it.
Finally got around to doing this... I picked up a used complete auto LSD carrier from the wreckers and swapped in my TRD unit. In the end after thinking about it long and hard I went with the 3.91 auto ratio instead of the 4.3. Reason being mostly for highway cruising and not wanting the RPM's to be so high to just cruise normally. So far I'm happy with the setup - did my figure 8's break-in and just changed the fluid again last night after that. I have my stock 3.7 LSD carrier now as a complete spare.
Unfortunately I don't have pics of the actual TRD unit being installed as I was on vacation during that time and my buddy went ahead with it.
Last edited by exist3nce; 12-05-13 at 10:34 AM.
07-30-13, 10:59 AM
#79
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SupraTT Cable Throttle Conversion
Been thinking about doing this mod for quite a while now to eliminate the DBW system and go with something more responsive.... the answer - Supra TT throttle of course 
Always nice to keep it in the family lol
Here's the stock DBW throttle assembly as removed off my car:
Comparing side by side with a 94 Supra TT stock throttle body to plan how this will all fit.... IS300 throttle opening ~56mm, SupraTT ~65mm
Measuring, cutting, and re-flanging the stock upper plenum piece to match the new throttle:
The new completed TT throttle assembly:
And now installed back on the car
The goal was to get it completed for Saturday night because I had a cruise planned with some bike buddies through the escarpments / countryside not far from my area.... luckily we met that goal and I had an awesome time Sunday! The difference in response is night and day - the car feels totally different to drive now! This is how it should have come from the factory
The catch: Up until this point my fuel level gauge has been working perfectly as it reads linearly from full down to empty - I have kept the factory MAF in the piping and the DBW system was functioning properly. Now that the DBW system has been completely removed (and I have several codes related to this) the fuel level gauge is reading strangely. Seems to be only reading in ~1/4 increments as has been discussed in many other threads when people have removed the MAF and the fuel level "calculation" by the ECU is no longer correct. It only samples the tank level once in a while as a backup to its calculations. Also the fuel econ gauge doesn't work properly which as far as I can tell is directly linked to the fuel level calculation (ie. when that gauge stops working - you can bet your fuel level will be off).
So now how to fix this.... I tried removing the "throttle request" sensor as well as the DBW motor itself from the old TB and plugged them in to see if this would make the stock ECU happy enough to give me proper fuel level. No luck on that.... it actually works for a couple min of driving before the system faults out again and my MPG gauge just sits at 80MPG / 0L/100km while moving and 0MPG / 20L/100km while stopped. When its in this fault mode, the fuel level does not move linearly... it just drops in large increments (about 1/4 or so) as has been documented by others. I have another idea in mind to try still ... I'll document how that works out
Always nice to keep it in the family lolHere's the stock DBW throttle assembly as removed off my car:
Comparing side by side with a 94 Supra TT stock throttle body to plan how this will all fit.... IS300 throttle opening ~56mm, SupraTT ~65mm
Measuring, cutting, and re-flanging the stock upper plenum piece to match the new throttle:
The new completed TT throttle assembly:
And now installed back on the car
The goal was to get it completed for Saturday night because I had a cruise planned with some bike buddies through the escarpments / countryside not far from my area.... luckily we met that goal and I had an awesome time Sunday! The difference in response is night and day - the car feels totally different to drive now! This is how it should have come from the factory
The catch: Up until this point my fuel level gauge has been working perfectly as it reads linearly from full down to empty - I have kept the factory MAF in the piping and the DBW system was functioning properly. Now that the DBW system has been completely removed (and I have several codes related to this) the fuel level gauge is reading strangely. Seems to be only reading in ~1/4 increments as has been discussed in many other threads when people have removed the MAF and the fuel level "calculation" by the ECU is no longer correct. It only samples the tank level once in a while as a backup to its calculations. Also the fuel econ gauge doesn't work properly which as far as I can tell is directly linked to the fuel level calculation (ie. when that gauge stops working - you can bet your fuel level will be off).
So now how to fix this.... I tried removing the "throttle request" sensor as well as the DBW motor itself from the old TB and plugged them in to see if this would make the stock ECU happy enough to give me proper fuel level. No luck on that.... it actually works for a couple min of driving before the system faults out again and my MPG gauge just sits at 80MPG / 0L/100km while moving and 0MPG / 20L/100km while stopped. When its in this fault mode, the fuel level does not move linearly... it just drops in large increments (about 1/4 or so) as has been documented by others. I have another idea in mind to try still ... I'll document how that works out
Last edited by exist3nce; 12-05-13 at 10:37 AM.
12-05-13, 10:39 AM
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Fall Plans and Update
Now that I've changed my picture links here, I'll continue to update this thread.. Here's the latest updates mirrored over from my.is
09-24-2013, 04:12 PM - Well it seems I've neglected my own build thread for some time... so here's a quick update.
Plans for this fall before the snow hits the ground:
- Swapping from SupraTT muffler to X-force Varex muffler and turn up the boost a little more + re-tune. I may also re-circulate the W/G dump back into the exhaust for a smoother/cleaner sounding car under WOT.
- Modifying the upper charge pipe to be able to fit a nice velocity stack on the turbo (if possible)
- TRD lip + repainting front end, passenger doors, rear passenger quarter, trunk and rear bumper.
Aside from that, the car has been running great and reliable all summer. From the time I brought it out of storage this year till now I've put about 8000km on it with no issues.
SupraTT cable throttle has been amazing, and I've found a relatively simple fix for the gas gauge issue when running a standalone, manual trans and eliminating the DBW
09-24-2013, 04:12 PM - Well it seems I've neglected my own build thread for some time... so here's a quick update.
Plans for this fall before the snow hits the ground:
- Swapping from SupraTT muffler to X-force Varex muffler and turn up the boost a little more + re-tune. I may also re-circulate the W/G dump back into the exhaust for a smoother/cleaner sounding car under WOT.
- Modifying the upper charge pipe to be able to fit a nice velocity stack on the turbo (if possible)
- TRD lip + repainting front end, passenger doors, rear passenger quarter, trunk and rear bumper.
Aside from that, the car has been running great and reliable all summer. From the time I brought it out of storage this year till now I've put about 8000km on it with no issues.
SupraTT cable throttle has been amazing, and I've found a relatively simple fix for the gas gauge issue when running a standalone, manual trans and eliminating the DBW
Last edited by exist3nce; 12-05-13 at 10:43 AM.
12-05-13, 10:40 AM
#81
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Fuel Level Gauge Fix!
09-25-2013, 02:38 PM
haha I let that slip as a teaser to see if anyone still cared since it went pretty silent after I posted about the issue LOL
Anyways after many hours of reading through diagnostic manuals and wiring diagrams to understand what is happening on the MPX bus and what data is flowing where, I came up with a simple solution to essentially trick it to keep working, however it only works for manual trans cars because the stock ECU will not see any real throttle position (needed for auto shift control).
Background Info:
First off there's no official information available from Toyota that I could find on EXACTLY how this system works. However, from the reading and experimenting I've done, my conclusion is that the fuel tank level you see on your dash is essentially calculated by the cluster based upon other data points it receives.
Some of these points are direct such as VSS which is wired directly to the cluster, while others have to flow over the MPX bus as serial data such as TPS and MAF. When the system is working normally (stock) it uses a variety of data to calculate your instantaneous fuel economy (your MPG gauge) and also "counts" or "totalizes" this data in the background to determine how much fuel you have used (fuel tank level). This system is kept in check by the occasional tank float level reading to make sure the dropping fuel level stays on track with the amount that is actually left in the tank. As to when exactly the system will check or what triggers it to check I haven't figured that out - but considering that the float level sensors are connected to the body ECU, this means it has to request the data from the body ECU over the MPX bus.
So now what happens when we mess with it? One thing I've found is that there are many different fault or failure modes the system can go into - some almost indistinguishable from others. The first key to knowing whether your fuel level will drop linearly as you drive is the MPG gauge - this gauge must continue to work. If this gauge just starts pointing right to the top (80MPG or 0L/100km) it means the fuel calculation has stopped working and you can guarantee that your tank level will stay right where it is - until the next time it references the floats.
In some failure modes the gauge will stop working as soon as you start the car, while in others it happens after a few mins of driving or a certain set of conditions is met. When I first ripped out all the DBW components it fell into the former category.
Solution:
After much experimenting I believe I have found a failure mode that forces the system to read from the MAF full time and still allows the fuel level to be accurate given these requirements:
- Cable throttle conversion using any T/B of your choice.
- Standalone/EMS controlling fuel and spark - it must also have its own dedicated TPS and wiring to read the actual throttle position. You cannot piggyback off the stock sensor and wiring.
- Stock ECU must still be in the car and functional and be able to interface with OBD2 software.
- Stock MAF must still be functioning in near-stock size piping and connected to stock ECU. MAF flow readings need be relatively accurate and should be verified via OBD2 at idle and free revving comparing to the diagnostic manual's factory numbers.
- The stock TPS (just the sensor) must be left plugged in to stock ECU - but it will not be reading any real throttle position. The sensor will just be chilling in your engine bay.
- The stock APPS (just the sensor) must be left plugged in to stock ECU - but it will not be reading any peddle position. The sensor will just be chilling in your engine bay.
- The stock TCM will not be used - do not plug it in.
Once those conditions are met, you can proceed with the following:
- Plug in an OBD2 scanner and start watching TPS - manually adjust the sensor until it is showing about 7.5% on the software. This is the value that I found to work for me - you may need to adjust yours a little more or less. Now you need to find some way to hold the sensor there permanently... perhaps some superglue, a custom fabricated bracket or shoving something in against the stopper with the just the right thickness ? In any event if the sensor is at 0 or not in the right position you will know it because the MPG gauge will stop working under some load and decent RPMs once you start driving.
- An error code for the TCM is normal, since it stays unplugged. You will also have a flashing TRAC light.
And that's about it! LOL
You will know if it worked for you because the MPG gauge will continue to work just like stock - if it shuts down at any time your fuel level is not being calculated. I would highly suggest after doing this to ensure the accuracy on your own car by driving through a tank until the light comes on and filling up again - the fill up should be 56-58L. You may want to carry a jerry can with a few liters of extra gas during your "testing" phase just in case - that's what I did!
Enjoy your working fuel gauge
haha I let that slip as a teaser to see if anyone still cared since it went pretty silent after I posted about the issue LOL
Anyways after many hours of reading through diagnostic manuals and wiring diagrams to understand what is happening on the MPX bus and what data is flowing where, I came up with a simple solution to essentially trick it to keep working, however it only works for manual trans cars because the stock ECU will not see any real throttle position (needed for auto shift control).
Background Info:
First off there's no official information available from Toyota that I could find on EXACTLY how this system works. However, from the reading and experimenting I've done, my conclusion is that the fuel tank level you see on your dash is essentially calculated by the cluster based upon other data points it receives.
Some of these points are direct such as VSS which is wired directly to the cluster, while others have to flow over the MPX bus as serial data such as TPS and MAF. When the system is working normally (stock) it uses a variety of data to calculate your instantaneous fuel economy (your MPG gauge) and also "counts" or "totalizes" this data in the background to determine how much fuel you have used (fuel tank level). This system is kept in check by the occasional tank float level reading to make sure the dropping fuel level stays on track with the amount that is actually left in the tank. As to when exactly the system will check or what triggers it to check I haven't figured that out - but considering that the float level sensors are connected to the body ECU, this means it has to request the data from the body ECU over the MPX bus.
So now what happens when we mess with it? One thing I've found is that there are many different fault or failure modes the system can go into - some almost indistinguishable from others. The first key to knowing whether your fuel level will drop linearly as you drive is the MPG gauge - this gauge must continue to work. If this gauge just starts pointing right to the top (80MPG or 0L/100km) it means the fuel calculation has stopped working and you can guarantee that your tank level will stay right where it is - until the next time it references the floats.
In some failure modes the gauge will stop working as soon as you start the car, while in others it happens after a few mins of driving or a certain set of conditions is met. When I first ripped out all the DBW components it fell into the former category.
Solution:
After much experimenting I believe I have found a failure mode that forces the system to read from the MAF full time and still allows the fuel level to be accurate given these requirements:
- Cable throttle conversion using any T/B of your choice.
- Standalone/EMS controlling fuel and spark - it must also have its own dedicated TPS and wiring to read the actual throttle position. You cannot piggyback off the stock sensor and wiring.
- Stock ECU must still be in the car and functional and be able to interface with OBD2 software.
- Stock MAF must still be functioning in near-stock size piping and connected to stock ECU. MAF flow readings need be relatively accurate and should be verified via OBD2 at idle and free revving comparing to the diagnostic manual's factory numbers.
- The stock TPS (just the sensor) must be left plugged in to stock ECU - but it will not be reading any real throttle position. The sensor will just be chilling in your engine bay.
- The stock APPS (just the sensor) must be left plugged in to stock ECU - but it will not be reading any peddle position. The sensor will just be chilling in your engine bay.
- The stock TCM will not be used - do not plug it in.
Once those conditions are met, you can proceed with the following:
- Plug in an OBD2 scanner and start watching TPS - manually adjust the sensor until it is showing about 7.5% on the software. This is the value that I found to work for me - you may need to adjust yours a little more or less. Now you need to find some way to hold the sensor there permanently... perhaps some superglue, a custom fabricated bracket or shoving something in against the stopper with the just the right thickness ? In any event if the sensor is at 0 or not in the right position you will know it because the MPG gauge will stop working under some load and decent RPMs once you start driving.
- An error code for the TCM is normal, since it stays unplugged. You will also have a flashing TRAC light.
And that's about it! LOL
You will know if it worked for you because the MPG gauge will continue to work just like stock - if it shuts down at any time your fuel level is not being calculated. I would highly suggest after doing this to ensure the accuracy on your own car by driving through a tank until the light comes on and filling up again - the fill up should be 56-58L. You may want to carry a jerry can with a few liters of extra gas during your "testing" phase just in case - that's what I did!
Enjoy your working fuel gauge
12-05-13, 10:42 AM
#82
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09-29-2013, 12:50 AM - So the W58 just took a dump.... which sucks, but I'm not overly surprised. At least I got 1 year out of it and about 10,000 km with some track use lol
Better things to come...
Better things to come...
12-05-13, 10:45 AM
#83
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09-30-2013, 10:39 AM - So while there was some bad news this weekend with the W58, I had just finished up some of my posted plans for the fall and thought I might as well share...
New axle-back section with Varex muffler, and the old SupraTT muffler in the background:
Shot of the entire exhaust with the new wastegate dump re-circulation tube:
As for the W58... I did some quick street tuning earlier Saturday afternoon at low boost (7psi) as we ran out of time to dyno tune Friday night (finished up the piping work at 4am lol). The plan was to come back Monday for the final tune and hit some new numbers. I was really liking the new sound of the open exhaust and it was definitely spooling up the turbo quicker...
Fast forward to that evening, and I was going out to dinner with the gf. About 10 mins into the drive I got on it in 3rd and then BANG, I thought I had just popped out of gear, but when I tried to select another gear and engaged the clutch I felt the unmistakable sounds and grinding of a broken trans
issed: Luckily I was driving right beside a Canadian tire plaza so I was able to coast in.
Whats next ? Definitely something stronger than a W58
CAA membership FTW haha
New axle-back section with Varex muffler, and the old SupraTT muffler in the background:
Shot of the entire exhaust with the new wastegate dump re-circulation tube:
As for the W58... I did some quick street tuning earlier Saturday afternoon at low boost (7psi) as we ran out of time to dyno tune Friday night (finished up the piping work at 4am lol). The plan was to come back Monday for the final tune and hit some new numbers. I was really liking the new sound of the open exhaust and it was definitely spooling up the turbo quicker...
Fast forward to that evening, and I was going out to dinner with the gf. About 10 mins into the drive I got on it in 3rd and then BANG, I thought I had just popped out of gear, but when I tried to select another gear and engaged the clutch I felt the unmistakable sounds and grinding of a broken trans
issed: Luckily I was driving right beside a Canadian tire plaza so I was able to coast in. Whats next ? Definitely something stronger than a W58
CAA membership FTW haha
12-05-13, 10:47 AM
#84
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11-05-2013, 10:31 AM
I would agree - It was a bit of a gamble but I got the whole package (W58 + flywheel + brand new ACT clutch) for such a decent price I had to give it a shot. The W58 was nicer to shift (may have been due to it being less miles/better condition). I'm happy that I got at least one full season out of it and that it didn't break in the middle of the summer LOL.
New updates coming soon
New updates coming soon
12-05-13, 10:49 AM
#85
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Coming back to life! (R154 swap in progress)
12-04-2013, 4:32PM - Finally I have an update... Between work and other obligations progress on this has been slow... but also the season (at least where I live) is over and winter is here so there's no rush anyways.
I'm going with the most proven and reliable route for now... R154 conversion! I actually had my eyes out for one for the past year or so and finally found what I was looking for. Also had to order a whole bunch of other bits to make the swap work. The R154 threads on this forum were very helpful!!
This was my parts list roughly:
MK3 R154
1JZ bellhousing
ACT clutch kit TS2-XTSS
1JZ OEM Toyota flywheel
C's short shifter for R154
Custom fabricated shifter housing extension
Custom modified stock driveshaft to fit R154
ARP 1JZ flywheel bolts
1JZ/2JZ flywheel bolt Locking Ring
Transmission/Bell housing bolts
Pressure plate bolt set R154
Center clutch release hub washers/clips only
R154 slave cylinder
Marlin Crawler vehicle speed sensor for R154
Marlin Crawler Urethane Shifter Bushing R154
Dowel Pin For R154 And W58 Flywheel (x3)
^ alot of the items above can be bought from Driftmotion, the custom stuff was done in house.
Note that with my used R154 trans, the selling also included the full stock clutch assembly, so I was able to re-use the center release hub piece and just replace the washers/clips. Also he included a stock slave with the hardlines - I decided to buy a new slave but re-use the hardlines.
Here's some comparison shots of the R154 vs W55/58 hybrid:
Fabricating the shifter housing extension
More pics to come..
I'm going with the most proven and reliable route for now... R154 conversion! I actually had my eyes out for one for the past year or so and finally found what I was looking for. Also had to order a whole bunch of other bits to make the swap work. The R154 threads on this forum were very helpful!!
This was my parts list roughly:
MK3 R154
1JZ bellhousing
ACT clutch kit TS2-XTSS
1JZ OEM Toyota flywheel
C's short shifter for R154
Custom fabricated shifter housing extension
Custom modified stock driveshaft to fit R154
ARP 1JZ flywheel bolts
1JZ/2JZ flywheel bolt Locking Ring
Transmission/Bell housing bolts
Pressure plate bolt set R154
Center clutch release hub washers/clips only
R154 slave cylinder
Marlin Crawler vehicle speed sensor for R154
Marlin Crawler Urethane Shifter Bushing R154
Dowel Pin For R154 And W58 Flywheel (x3)
^ alot of the items above can be bought from Driftmotion, the custom stuff was done in house.
Note that with my used R154 trans, the selling also included the full stock clutch assembly, so I was able to re-use the center release hub piece and just replace the washers/clips. Also he included a stock slave with the hardlines - I decided to buy a new slave but re-use the hardlines.
Here's some comparison shots of the R154 vs W55/58 hybrid:
Fabricating the shifter housing extension
More pics to come..
12-06-13, 02:21 PM
#86
Driver School Candidate
Nice car! Alot of work went to this. I would agree the title needs to change since the motor is no longer a true GE one.
How did you fabricate the LS430 lights into your stock ones? I see the pics but not really understanding the method...plus how did you 'aim' them? making sure they are shooting the road?
Thanks!
Eddie
How did you fabricate the LS430 lights into your stock ones? I see the pics but not really understanding the method...plus how did you 'aim' them? making sure they are shooting the road?
Thanks!
Eddie
