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just read your build after helping you in the performance forum, the maps are looking very nice.
I think you can probably creep into the 40 degree spark range for cruise loads and take a few degrees off that 900 rpm column no need to work your motor that hard at idle, i would even try a run with lowering the 1250 column as the motor really isn't "loaded up" yet so extra timing may just end up making it go slower vs using the right timing, try and get most of the advance in (30ish) by/around 2000rpm's as that's when the motor is loaded up pretty well, otherwise its looking good to me.
just read your build after helping you in the performance forum, the maps are looking very nice.
I think you can probably creep into the 40 degree spark range for cruise loads and take a few degrees off that 900 rpm column no need to work your motor that hard at idle, i would even try a run with lowering the 1250 column as the motor really isn't "loaded up" yet so extra timing may just end up making it go slower vs using the right timing, try and get most of the advance in (30ish) by/around 2000rpm's as that's when the motor is loaded up pretty well, otherwise its looking good to me.
Hi, thanks! I need to do a lot of smoothing in the VE table, but I dont see the point until I get the MAT compensation table working better. The stock values are to high and the VE changes a lot with temperature.
About the timing table, I idle the car at 700RPM, but I will look into lower timing in this region. 30* by 2000 sounds very agressive. Im not saying you are wrong, and you definately have more 1UZ experience then me! But I hope its OK if I ask if this is guesswork or if you have tuned a 1UZ and for some other reason know that this is ok to do? My knock detection is not up and running yet, so Im a bit worried about running to much timing at this point .
On a side note, I just recieved my magnaflow high flow cats. Im still waiting for the headers, but hopefully they will arrive in cople of weeks or so. Once they are installed, I can book a dyno for a spark hook test. I will spend some time on cruising and midrange on the dyno and of course update this thread with my results. In the meantime I will attempt to get the knock system and MAT correction working properly. Once that is functioning I will look into the closed loop idle tables and hopefully have a very good tune ready for the dyno, reducing the very high cost of Norwegian dyno opertors.
your spark table above has values larger than 30 @ 2000 rpm's ( I am referring to the least loaded cells or idle load row of the spark map) so I am not sure what you mean by more timing I actually meant your timing looks good @ 2000 rpm's but your ramp up (the region between idle and the 2000rpm plateau into cruise) is going up too fast, and you could be knocking between 900rpm and 1600rpm's (hard to know without a knock sensor). without knowing for sure I would have lower numbers towards 900rpm's (there is no reason a 10:1 compression motor needs 17 degrees of timing at 900 rpm's you are just raising the combustion temps for a minimal or adverse affect in performance) and keep the same end numbers at 2000 rpm but increase more slowly between.
you do not want most of your advance preset before 2000rpms's generally speaking, as in you do not want to hit most of your advance at 1400 or 1600rpm's.
This is not specific to a 1uz at all its more of the different sections of the timing map and how loaded a motor needs to be. Riding the edge of the advance curve like you are will minimize your emissions at the expense of power (until the cylinder temps get outrageously high and the nox numbers shoot up), but I am just assuming that maximizing emissions is not what you are trying to do.
the air temp, I see alot of people have it to add in % when very cold, but above lets say like 90 deg F it should start to zero out the trim, as in once you hit 30 degrees C, it should be 100% and stay at 100% until its at an absurd temperature then it should still be 100% or some people like to ramp up the fuel as a safety then. it looks like right around the temp I said (30 in C), your map goes to 100% which is 0 trim and right, but then it starts to go down little by little. this will cause fluctuations in the main map, normally you have a better correction with a 0 trim across all the normal operating air temps (100% in your software), and then optionally you can have the trim go way up at the end at a way too high air temp like lets say 200 F you can set it to go from 100% to 125%, and thats to let you know something is up when the car runs overly rich that something is wrong with your air temps.
the idea is that small fluctuations in air temp is handled by the o2 sensor and the richness of the main basemap, not depending so accurately on the air temp sensor that the base table look up is always fluctuating and then the slow to react o2 after that, its like a double correction happening too slowly... so it would get to 100% at 30C like you have but should stay 100% till like 90C and after that you can have it ramp up for the feature as mentioned above, cause if you air temp is over 200 degrees F then you have a serious problem you should not let the ecu try and make up for that by removing fuel, cause although it would theoretically help the AFR, it might also non-theoretically cause the motor to run hot and lean then when you could be using that extra fuel to cool the combustion down. 99.999% of the time your vehicle will never enter this air temp its only in that .01 when there is a problem or heatsoak.
your spark table above has values larger than 30 @ 2000 rpm's ( I am referring to the least loaded cells or idle load row of the spark map) so I am not sure what you mean by more timing I actually meant your timing looks good @ 2000 rpm's but your ramp up (the region between idle and the 2000rpm plateau into cruise) is going up too fast, and you could be knocking between 900rpm and 1600rpm's (hard to know without a knock sensor). without knowing for sure I would have lower numbers towards 900rpm's (there is no reason a 10:1 compression motor needs 17 degrees of timing at 900 rpm's you are just raising the combustion temps for a minimal or adverse affect in performance) and keep the same end numbers at 2000 rpm but increase more slowly between.
you do not want most of your advance preset before 2000rpms's generally speaking, as in you do not want to hit most of your advance at 1400 or 1600rpm's.
This is not specific to a 1uz at all its more of the different sections of the timing map and how loaded a motor needs to be. Riding the edge of the advance curve like you are will minimize your emissions at the expense of power (until the cylinder temps get outrageously high and the nox numbers shoot up), but I am just assuming that maximizing emissions is not what you are trying to do.
the air temp, I see alot of people have it to add in % when very cold, but above lets say like 90 deg F it should start to zero out the trim, as in once you hit 30 degrees C, it should be 100% and stay at 100% until its at an absurd temperature then it should still be 100% or some people like to ramp up the fuel as a safety then. it looks like right around the temp I said (30 in C), your map goes to 100% which is 0 trim and right, but then it starts to go down little by little. this will cause fluctuations in the main map, normally you have a better correction with a 0 trim across all the normal operating air temps (100% in your software), and then optionally you can have the trim go way up at the end at a way too high air temp like lets say 200 F you can set it to go from 100% to 125%, and thats to let you know something is up when the car runs overly rich that something is wrong with your air temps.
the idea is that small fluctuations in air temp is handled by the o2 sensor and the richness of the main basemap, not depending so accurately on the air temp sensor that the base table look up is always fluctuating and then the slow to react o2 after that, its like a double correction happening too slowly... so it would get to 100% at 30C like you have but should stay 100% till like 90C and after that you can have it ramp up for the feature as mentioned above, cause if you air temp is over 200 degrees F then you have a serious problem you should not let the ecu try and make up for that by removing fuel, cause although it would theoretically help the AFR, it might also non-theoretically cause the motor to run hot and lean then when you could be using that extra fuel to cool the combustion down. 99.999% of the time your vehicle will never enter this air temp its only in that .01 when there is a problem or heatsoak.
Hi, OK now I understand, I thought you were suggesting 30* WOT at 2000RPM. Thats some really good advice on the timing, thanks, I will look into this! As for emissions, I only need them to be good at idle as that is the only thing tested in our 2 year smog tests.
Your logic on the air temps make perfect sense. My AFR is fluctuating from day to day, I will try to zero out the table @30C and then work on the low temp IAT values. I will frequently have 0C-20C, so Ill still need some tuning, but right now my filter is still in the engine bay and 30C is common.
Thanks for your advice, this is really helpful!
No updates on the car though. Still waiting for those headers, and I have not had any time to work on anything else.
Mini update: I have been up to the neck with work lately, as I just started a business and the work load is quite huge at the moment. So there is so little time for any work.
However that is just as well, as PPE is really taking their time with the headers. They were delayed and are currently beeing coated in that black finish I ordered for stelthy looks.
Im currently looking for wheels and sideskirts. II have some OK wheels now, 8.5" and 9.5", but Im looking for something with lighter weight. As for tires, Im considering the Michelin pilot super sport tires. 265 rear and 245 fronts should do the job both on and off the track.
As for styling, I have a Wise front lip, and Im looking for some side and rear bumper skirts. Any suggestions?
Today I finally found some time for the Lexus. I took it for a drive for VE adjustments, and the VE table is looking quite good now! There are still some areas that need a bit more work, but Im not interested in making it perfect until the exhaust is improved anyways. But PPE is really taking their time on those headers, and there are a few 1/8 mile races and other events coming up soon, so I figured I could give it some more work in case I want to enter. Here is the latest revision of the VE table:
During the VE adjustments I did 110mph or so and noticed a humming noise from the rear differential.. The diff has become "clunky" lately, but this time it made a lot of noise. So I got it to the garage and on too the lift - I was going to replace the oil anyways - And I noticed the diff had a terrible noise from the driver side bearing area. Not good.
A quick disassembly revieled the source of the noise:
Lucky for me I already had a replacement - The Torsen T2-"racing" diff. Im hoping to install this tomorrow and go for a test drive! Perhaps a youtube video will be added shortly.
So I did a 0-60mph test today. When I got the car it was about 7 seconds. With the megasquirt and open diff it was 6.1. Now it is 5.7seconds! On 225mm wintertires - Cant wait to get the 275mm tires on!
The tune is a bit better, so the LSD is not the only mod, still, this is beyond expectations and Im so far really happy with the new LSD!
Now, where are those headers? They should net another 20hp+ over most of the RPM range.....
a LSD is great on the SC! much more handling and a stiffer rear. i changed from the open to a supra LSD and now a TRD 2 Way... great difference, with the 2 way much more traction, but less sliding
a LSD is great on the SC! much more handling and a stiffer rear. i changed from the open to a supra LSD and now a TRD 2 Way... great difference, with the 2 way much more traction, but less sliding
My first choice would be the TRD diff, but I could only find them complete with a differential housing, and that would simply be to expensive in shipping over here. But the LSD upgrade totally transformed the car. It did however make the terrible stock suspension feel even worse. I was planing to wait for my bushing kit before I installed the TRD coilovers, but now Im thinking maybe I should just install them to get rid of the "boaty" ride. I almost fell out the window today when I pushed the gas going uphill through a long turn.. Thank god for seatbelts and those beefy doors
First impression is that the headers look great! They look like a tight fit on the engine /firewall but I guess this has been done before. In the picture is also the new high flow cats from Magnaflow that I will install to keep the car road legal - ish.
I also went shopping, and Im waitng for stoptech rotors and brake pads for Supra MKiV. I already have a calippers, and Ill start working on them first thing. They will get new gaskets, and a new colour as corrosion white really isnt my favorite. I also got a set of new bushings for the front suspension to complement the TRD coilovers.
Im hoping with some luck to get this done over the weekend, and then Ill book the dyno by the end of the month.
i have this thread bookmarked because i'll be doing basically everything exactly the same. some awesome info in here, please document the header install, there's not much info on how to install headers.
Will do. I had a look at the stock headers just to imagine how the new ones would be to install, and I really hate myselfe right now for buying them. But I guess there is no way back
Anyways, I made some more progress last night, and replaced the overly comfortable stock coilovers with the TRD coilovers that I got for 300$.
I have absolutely no comparison to any other supra/sc coilover, so I cant say if they are better than this or that. First impressions is of course is that they are much harder than stock with the 11/9 (615/521) FR springrates compared to the stock 6.3/3.2 357/182 and those Bilstein shocks said to be stiffer than Yellow bilsteins for JDM Supras. Im yet to test the handling, but the grip has improved a lot in low speed cornering. Ill come back with results when I have tested it more properly.
I noticed Im yet to post any pictures of the car, so I figured I could upload some. No time for washing the car though.
The previous owner painted it with a flat black "clear" coat to seal the paint. I would prefer a clear coat on it, but time and money does not allow that at this time. Im thinking I should get some stickers or something to "break up" the flat black colour, but Im not sure what to do without making the car look like some freakshow from "fast and furious".
Hopefully my next update is headers. Im not the best at taking pictures of my work, as Im always in such a hurry, but Ill do my best this time
Will do. I had a look at the stock headers just to imagine how the new ones would be to install, and I really hate myselfe right now for buying them. But I guess there is no way back
What aspect are you unhappy with, the tight space for installing them?
Im thinking I should get some stickers or something to "break up" the flat black colour, but Im not sure what to do without making the car look like some freakshow from "fast and furious".
Decorate each body panel with something different themed from each of the movies.
Originally Posted by Sc400NL
i know its not easy for us euro owners
I've read that MKIV Supras are much, much cheaper outside of North America, and are basically considered economy sports in Europe ... much like the SC is here. Is that perhaps why there's less of a European SC community represented here on CL?
02-18-15, 09:55 AM
