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You are probably washing out the spark some with the distributor. What is your plug situation like? You want something like the Bkr6eix and gap them lower for the distributor. Bkr7eix if you are running over 14 psi.
You can start at the .032 and work your way down to maybe the .024 area looking for where it stays smooth. If you have vvti coils or more advanced coil on plugs you can run more gap before running into the issue.
Some run an amplifier like the HKS DLI on the stock coil, it helps out with the spark issues but I have never run one. I would plan to swap over to coils and ditch the distributor, it will run smoother as well.
Ali,
I took the gap on my plugs from .032 to .026 and the car is running way, way better. It pulls very smooth through all gears. Thanks for the advice.
Hi everyone. I have a 96 auto sc300 and a 92 5 speed sc300. The motor for the 92 is being rebuilt and the 96 I just installed the cx racing turbo kit. My question for the guru is what is a good way to tune the car on the stock ecu? So far I’ve installed a high flow fuel pump, did the valve cover gaskets and spark plugs + wires, and new whole distributor recently before the kit was in, and I’m going to get injectors soon. My plan is to pull the plugs and gap them down since they only have like 150 miles on them and I wanna say I went with the ngk’s you recommended by pure chance. Any idea if I can retard the timing a certain amount just so it can accept a little bit of boost or is there a cheap piggyback or ecu option? Also, idk if it’s a ring issue or what not but I’ve driven the car since installing the kit maybe 50 miles as a shake down just to see if anything is leaking or needs adjusting which of course it does, but if it starts to build even a little bit of boost, when I let off the throttle it will blow a cloud of blue smoke and immediately stop. Could that be a pcv issue or valve seals or rings or something else? Eventually I’m going to build the head and give the motor a freshen up but I’d like to get the car to a point where it can use the boost, only looking for 250ish horsepower at the moment. Thanks for your time
look into the tt ecu mod in the main SC section to use a jdm gte ecu, gte map sensor and 440cc injectors.
either that or go standalone are the best options these days. the stock ge ecu does not do well with boost and will likely cause detonation at some point.
You could have pcv issue, valve stem seals blown, ring issue, turbo seal leaking oil (make sure right feed and drain sizes and no kinks).
Did you check the timing when you did the distributor with a timing light. I would verify base timing before building any boost especially on the stock ge ecu.
look into the tt ecu mod in the main SC section to use a jdm gte ecu, gte map sensor and 440cc injectors.
either that or go standalone are the best options these days. the stock ge ecu does not do well with boost and will likely cause detonation at some point.
You could have pcv issue, valve stem seals blown, ring issue, turbo seal leaking oil (make sure right feed and drain sizes and no kinks).
Did you check the timing when you did the distributor with a timing light. I would verify base timing before building any boost especially on the stock ge ecu.
Thank you for the advice, I’ll search the thread for tips on the ecu mod. Talked to my machinist and we are taking the rebuilt block from the 92 and doing a lil switcheroo, by putting it in the 96 (so there’s not a lot of down time) and rebuilding the 96 block to put into the 92. I’ll post some pics when the build gets started and keep everyone updated. Also another question, what diagnostic system does the jdm ecu use? The 92 is obd1 and the 96 is obd2. Would it affect plugging a scanner in for either if I swap the ecu? I have no idea on jdm diagnostic systems.
The JDM is JOBD, so no the 96 wont retain obd2 if you swap to a jdm ecu.
JOBD will still blink out the CEL codes same as obd1 so you won't really notice in an obd1 car.
Thanks in advance for any thoughts you might have.
As discussed earlier in this thread, I am running the NA-T setup you developed for 95 SC300 with a distributor. I was getting some spark washout at about 4,500 rpm. I closed the plug gap down to .026" and that helped a lot. I have since added an MSD ignition and blaster coil. So now it is really nice. It pulls so hard right up to 6,100 RPM. Then it stumbles hard. Not sure if there is a limiter in the ECU? I have the limiter on the MSD set for 7,100 rpm.
Any thoughts why it might be cutting out or stumbling at 6,100 rpm?
My ECU part number is 89661-14501 from a 95 Toyota JZA80 Supra 2JZ-GTE MT.
If it is running well otherwise I would just suspect the normal things like maybe you are building more boost now up top and thus hitting boost cut.
Boost cut takes the throttle input away for several seconds (nothing will happen and it will slowly decelerate for a couple seconds) and it will flash the CEL at you during that time.
If that is not the case, then you could just be blowing/washing out the spark at a higher rpm now, see if you can slowly accelerate to 6800 which is where it should cut out normally, MT ecu might even be a hair higher than that.
Have you done the distributor cap and rotor ever? sometimes those get overlooked. If the ignition system is working fine it should be able to keep up, you might have to gap down some more.
I still recommended going to vvti coilpacks over any upgrades for the stock coil. The charge time just isn't ideal for one coil supplying 6 cylinders with forced induction.
Some wont go any less than individual cop for each cylinder for pretty much this reason, they want to run a larger gap with higher boost levels.
I wouldn't be surprised if you have to go to .021 with the stock distributor setup to get a clean pull in different weather conditions.
edit* a quick search I saw this thread on SF about rpm and msd igintion. I think you are still getting the IGF signal is what seem to be talking about, but maybe there is something else going on there with the msd and the stock ecu.
Never ran it before so not a huge help unfortunately. https://www.supraforums.com/threads/...try-it.456696/
My 2007 Lexus IS250 RWD is in need of a new torque converter. I bought one off AutoZone (part number TO98) that says it will fit but when I pulled the old one out the size was larger. Would the AutoZone part work our would I need to find a torque converter with the exact same dimensions?
Not the correct section but even if it does slide on and bolt to the flex plate why put a smaller autozone torque converter in there?
Think about the labor of dropping the transmission and reinstalling it again when that unknown quality part bites the dust.
I would get a new OEM one, or worst case find a good used OEM one.
Also the TC on toyota automatics rarely go bad, so maybe look into why or if your original is even bad in the first place.
If it is running well otherwise I would just suspect the normal things like maybe you are building more boost now up top and thus hitting boost cut.
Boost cut takes the throttle input away for several seconds (nothing will happen and it will slowly decelerate for a couple seconds) and it will flash the CEL at you during that time.
If that is not the case, then you could just be blowing/washing out the spark at a higher rpm now, see if you can slowly accelerate to 6800 which is where it should cut out normally, MT ecu might even be a hair higher than that.
Have you done the distributor cap and rotor ever? sometimes those get overlooked. If the ignition system is working fine it should be able to keep up, you might have to gap down some more.
I still recommended going to vvti coilpacks over any upgrades for the stock coil. The charge time just isn't ideal for one coil supplying 6 cylinders with forced induction.
Some wont go any less than individual cop for each cylinder for pretty much this reason, they want to run a larger gap with higher boost levels.
I wouldn't be surprised if you have to go to .021 with the stock distributor setup to get a clean pull in different weather conditions.
edit* a quick search I saw this thread on SF about rpm and msd igintion. I think you are still getting the IGF signal is what seem to be talking about, but maybe there is something else going on there with the msd and the stock ecu.
Never ran it before so not a huge help unfortunately. https://www.supraforums.com/threads/...try-it.456696/
Ali,
Thanks for getting back. I will try to run the rpm up slowly and see if it cuts at the same place. I have replaced the cap and rotor when I did the NA-T. I may end up having to run COP. I will play with it some more and see if I can get some more feedback from the car.
Thank you that does make sense. I just been going off advice from shops and Youtube. The problem is my car wont go past 4th gear and I was guessing it was the torque converter so I just went to the place that usually has the parts that work.... AutoZone. but they only had the one model. My light display also lights up like a Christmas's tree. Check engine light, check VSC, and traction control. When I replaced the valve body and all the shift Solenoids I was still having the same trouble. So my next step was to assume the torque converter. Do you think this would fix my problem or should I just get a whole new trans?
If it is running well otherwise I would just suspect the normal things like maybe you are building more boost now up top and thus hitting boost cut.
Boost cut takes the throttle input away for several seconds (nothing will happen and it will slowly decelerate for a couple seconds) and it will flash the CEL at you during that time.
If that is not the case, then you could just be blowing/washing out the spark at a higher rpm now, see if you can slowly accelerate to 6800 which is where it should cut out normally, MT ecu might even be a hair higher than that.
Have you done the distributor cap and rotor ever? sometimes those get overlooked. If the ignition system is working fine it should be able to keep up, you might have to gap down some more.
I still recommended going to vvti coilpacks over any upgrades for the stock coil. The charge time just isn't ideal for one coil supplying 6 cylinders with forced induction.
Some wont go any less than individual cop for each cylinder for pretty much this reason, they want to run a larger gap with higher boost levels.
I wouldn't be surprised if you have to go to .021 with the stock distributor setup to get a clean pull in different weather conditions.
edit* a quick search I saw this thread on SF about rpm and msd igintion. I think you are still getting the IGF signal is what seem to be talking about, but maybe there is something else going on there with the msd and the stock ecu.
Never ran it before so not a huge help unfortunately. https://www.supraforums.com/threads/...try-it.456696/
Ali, I've been doing some reading and found a post on supraforums that says if you have the NA tach running on a GTE ECU with the little jumper wire soldered on, the tach will start to read inaccurately as the RPM climb. So in other words, I am fuel cutting at 6,800 rpm even though the tach is reading about 6,200 rpm. Thoughts? Have you heard this before? This is what it feels like. It is a hard cut at 6,200. Not like a spark washout.
Hey Bruce, interesting read somehow I have not come across that before. On my SC I didn't have that issue, or at least I don't remember it being so off.
Maybe it is a supra na tach cluster thing, or depends on the health of the stepper motor and where its sitting when it should be reading 0 or idle rpm.
Without obd2 the main ways to get an actual rpm reading would be to have one of those timing lights on coil 1 with an rpm readout.
There was also a thread on here about accessing the obd1 on the toyota ecus, cant remember if it also works for jobd ecus for the JDM stuff.
That would also give you rpm readouts to compare to. If you have a safc or other piggyback you could see rpm there as well.
I would ask Gerrb, hes swapped so many supras that if its a thing he would likely know about it, but I remember in his threads mentioning just bypassing the resistor.
I know I have moved the stepper motor by accident on other toyotas before and then had to nudge the needle up and down till it was in the right spot with the key on.
If its off a little bit in the lower rpm range, it might be more off in the upper range then is a guess.
Let me know if you figure it out, this one is new to me. I am about to bypass the rpm board on a 97 land cruiser that I'm swapping a 2jzge into with vvti coils, that will be on aem at first so I will see if there is a discrepancy there.
I always take care now to not let that needle move when I am making modifications.
Another last thought in case it isn't the tach and has something to do with the coil/ignitor. You did the mod with the new ignitor and the old distributor and coil setup.
Maybe the 1 coil is creating more noise than was intended at the ignitor vs 3-6 coils each having more time to charge and fire, so its just not getting clean inputs at the ignitor to feed to the tach line.
The IGF and Tach line are more or less signals created from the inverse magnetic field of the coils firing, so it might just not be registering all the IGF's perfectly up top. The ecu will keep going as long as it is getting some IGF's I want to say.
The other thing that could play in is the MSD box, it creates multiple fire events for each firing or something like that, so it could be confusing the ignitor at higher rpms affecting the tach output.
Just guesses I don't have experience with the MSD box or coil on these cars. I know people run the HKS DLI all the time and still first I am hearing about the tach difference.
08-30-23, 07:36 AM
