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Discussion Starter · #1 · (Edited)
Hi guys,

Just a short info about the car:

It has a PHR Street Torque kit with a 6466, PHR full fuel system with ID1000 running 98RON pump gas and an ATF built auto w/ IP4000 stall. It has a VEMS Standalone ECU for the engine and the transmission runs off of the stock trans ECU.

I know that a lot of you will recommend ProEFI, however currently that is not an option for me as I am located on Iceland and the only tuners here know either VEMS or AEM, plus this is the only automatic Supra in the country. Might possibly go down that road later with some kind of a remote tune.

I would really appreciate it to get your opinion on my VE and Ignition tables just to get different views and see if more experienced individuals have a valuable input for me. Don't know how to upload a log...

SupraLog - VE Table.jpg
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SupraLog - Ignition Table.jpg

It is running about 24psi without any knock. Most turbo guys here are running up to 30psi on 98RON pump, however I know that is not popular is the US with the 93.

AFR's are around 11.2 - 11.6 under WOT

Your input/comments are really appreciated, and if you need any further information, just let me know.

Note. I feel the car should be faster/quicker as it only traps 116mph on the track (no boost leaks whatsoever)
 

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-interpolate the values from 2000rpm to idle regions so that the value is always changing in a way that makes sense.

suggest looking at and comparing advance spring/weight combinations for mechanical advance distributors
and comparing with the factory LS timing tables from various ECU

The old method will work, try to get a full timing in by 2400-2800rpm, then go soft through peak torque if the camshaft is oem or compression is a bit higher than comfortable with fuel and temperature.
More efficient combustion chambers need less timing/can get by with less timing. I found 13* adequate right where you have 12 and 14 so thats good.

The numbers in the midrange are good but heres a tip. Use the sidebar to increase resolution in regions where the car cruises frequently or is used often, and fine tune it to the range of 2-4kpa resolution.
This will unlock fuel savings by allowing discriminant timing values for exact cruise vs weight and prevent unnecessarily large accel enrichment or map dot values in general.
If you'd like an example I can add one

Also, as to why it feels "slow" or down on power,
Usually after a street tune I say the same thing for a given combo.
Then I goto the dyno and find out it's about 40-80hp low for various reasons.
IF the engine is in good shape and there are no leaks (boost, compression) then you may need to do a little dyno tuning to squeeze the last bit out of any given combo. For example if the turbo is 'worth' 500rwhp usually I find my street tunes show up to the dyno around 440rwhp and it takes a little finesse to squeeze every last drop out of it on the rollers. Which then you try and translate to the track but be conservative because dyno roller can accelerate faster than the actual car in "high" gears.
 

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The map doesn't really look beautiful but that won't necessarily affect power, realistically the important part is if the timing numbers are in the right range for the fuel etc that it's on - they certainly don't appear "soft"... if anything I'd be worried about knock if your 98RON is anything like ours, but from what you say that is ok.

Beyond that, datalogs showing what is actually happening would be good. The fact that it is only running 116mph with a 6466 running 24psi on 98RON seems odd - that kind of setup with decent headwork should be well over 120mph imho. Makes me wonder how consistent the boost control side of this is performing. You aren't running stock cams, right?
 

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Discussion Starter · #4 ·
-interpolate the values from 2000rpm to idle regions so that the value is always changing in a way that makes sense.

suggest looking at and comparing advance spring/weight combinations for mechanical advance distributors
and comparing with the factory LS timing tables from various ECU

The old method will work, try to get a full timing in by 2400-2800rpm, then go soft through peak torque if the camshaft is oem or compression is a bit higher than comfortable with fuel and temperature.
More efficient combustion chambers need less timing/can get by with less timing. I found 13* adequate right where you have 12 and 14 so thats good.

The numbers in the midrange are good but heres a tip. Use the sidebar to increase resolution in regions where the car cruises frequently or is used often, and fine tune it to the range of 2-4kpa resolution.
This will unlock fuel savings by allowing discriminant timing values for exact cruise vs weight and prevent unnecessarily large accel enrichment or map dot values in general.
If you'd like an example I can add one

Also, as to why it feels "slow" or down on power,
Usually after a street tune I say the same thing for a given combo.
Then I goto the dyno and find out it's about 40-80hp low for various reasons.
IF the engine is in good shape and there are no leaks (boost, compression) then you may need to do a little dyno tuning to squeeze the last bit out of any given combo. For example if the turbo is 'worth' 500rwhp usually I find my street tunes show up to the dyno around 440rwhp and it takes a little finesse to squeeze every last drop out of it on the rollers. Which then you try and translate to the track but be conservative because dyno roller can accelerate faster than the actual car in "high" gears.
Thank you for your input! By interpolating the values, I assume you are referring to the fuel table.

Using sidebar you are referring to in the fuel table to increase resolution makes totally sense as I often notice excessively rich fuel mixture on my a/f gauge on deceleration and especially daily driving on light load (2500-4500rpm).
I would really appreciate an example if you have time for it,

The car was actually tuned on a dyno, however that dyno did not have a brake in it. We increased boost via EBC, but then when on the street, it seems as the DC input on it wasn't working properly as the boost was much lower on the street (about 5psi lower boost)

It made about 391whp/394ft lbs, which I find a little odd.

We then adjusted it slightly on the street for boost by speed reference and that seemed to work okay.

I am however having it put on another dyno in a week or two, which has a brake in it for better tuning basis and more accurate numbers, even though they don't mean as much with a high stalled auto.

First drag strip practice of the season it about 2-3 weeks away. We only get about 4-6 practices over the whole year, so I got to use every chance I get.

The map doesn't really look beautiful but that won't necessarily affect power, realistically the important part is if the timing numbers are in the right range for the fuel etc that it's on - they certainly don't appear "soft"... if anything I'd be worried about knock if your 98RON is anything like ours, but from what you say that is ok.

Beyond that, datalogs showing what is actually happening would be good. The fact that it is only running 116mph with a 6466 running 24psi on 98RON seems odd - that kind of setup with decent headwork should be well over 120mph imho. Makes me wonder how consistent the boost control side of this is performing. You aren't running stock cams, right?
I really appreciate the input!

Over here guys have been running 98RON for over 10 years on high boost settings without issues, also a buddy was running a mid 10sec Supra on 28psi for many years - that was about 3-4 years ago and it is still running well on the same engine.

I am actually switching tuners to a more experienced 2JZ tuner locally who tuned that Supra. Hoping he will smooth out my setup and make it more reliable in the long run.

I am running stock USDM cams, yes. It does fall off a little on the top end on the dyno, however I am only reving to the stock rev limit of 6700.
 

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There are some 2L using 37psi of boost by ~4000rpm with straight 93 octane (0* of timing there too) that make 600rwhp apparently
https://www.evolutionm.net/forums/e...in/754079-bw-s362-sxe-twinscroll-project.html

Once I saw that I threw away the rule book for pump gas boost. I'd say its less about boost (the pressure number in the intake of 30-80psi) and more about the pressure in the cylinder that peaks at some 2000psi or whatever. And keeping the air cool enough not detonate of course.
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for decel there must be some fuel-cut function. Deceleration fuel cut.
It isn't really recommended to lean the fuel map out in high vacuum areas. Just in case you are coming on the throttle and especially at higher rpms. Just leave the a/f there reasonable 13's 14's
and resolve the decel fuel cut function
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On the side of the map you can change the number that it corresponds to. If the engine cruises 48-63KPA then adjust the side to give more cells in that region, for example this:
20 40 60 80 100 120 140 160 180 200 KPA

is a typical line given from a factory/default.

Whereas this:
25 35 45 50 55 60 65 75 90 120 150 170 190 210 KPA

Is giving more resolution through the mid-regions and less resolution where it isn't needed.

That way you can fine tune the box at exactly 55 or 60 or make one for exactly 62KPA or whatever. The software averages from nearby cells so those are just as important as the 'main' cell, and when the resolution is poor the a/f can swing wildly for just a small error %.
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stock cams severely limit power potential. I wouldn't worry about power output at all until cams are changed. Use a low-lift cam and the matching spring (same manufacturer) if possible.
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When I said interpolate, I mean the TIMING values. Never use the same timing value in a cell side by side. It should always be moving.
digital electronics aren't *that* accurate. If you command say 15.000 the actual timing results will be more like 15.004, 14.998, 15.007, 15.0011, 14.999, 15.002, etc... this could create an oscillation in the output, wasteful of energy, inefficient. Digital microprocessors need a direction, going UP or going DOWN. They are either ON or they are OFF. They hate being "in the middle / not moving" It will never run as good because the mechanical part of the engine *IS* timed perfectly, it's rotating frequency will always be some rate of change + initial velocity component.
 

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On a 6 speed he would probably trap 122 even on those stock cams. The converter is taking power away as seen by his torque numbers. Cams definitely could help.
 
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