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I run a SC. Finishing my intercooler and running a .4" smaller pulley. My new boost gauge hasn't arrived yet. I kno I'm under 10psi, but I'm trying to calculate how much smaller of a pulley I can run...
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How much boost with stock injectors & fuel mapping
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I run a SC. Finishing my intercooler and running a .4" smaller pulley. My new boost gauge hasn't arrived yet. I kno I'm under 10psi, but I'm trying to calculate how much smaller of a pulley I can run...
not on the same motor.
yes, it will vary even on the same motor. A GT28RS will flow considerably less than a GT42R at 10psi no matter which motor they are attached to.
I didn't want to muddy this thread up anymore so I started a new one with some fun SAFARI turbo facts, dyno results, and AFR numbers.
https://forum.ih8mud.com/80-series-...o-dyno-results-afr-questions.html#post7525300
Landtank - I'd love for you to check it out as I am considering your MAF plus upping the boost to 10psi.
https://forum.ih8mud.com/80-series-...o-dyno-results-afr-questions.html#post7525300
Landtank - I'd love for you to check it out as I am considering your MAF plus upping the boost to 10psi.
If he is making 20 psi on a !FZ-fe with a small turbo and then making 6psi on the same motor with a large turbo how is it the same air flow and HP?
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- #26
Rick, I think they are saying it is NOT the same airflow. For instance, s pressure washer @ 1000psi has considerably less flow (maybe 0.75GPM) than a faucet with 40 psi (3 GPM).
A turbocharger is a exhaust driven compressor[centrifugal] and the pressure it produces is generally irrelevant, the amount of air it moves is what is important. Fuel systems need to be though of in hp ratings not pressure.
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Sorry I'm a little late to recheck this here thread but to answer the question, no, nothing altered at all with the timing.
Crap, I feel like I'm wussing out here.
What do you have for fuel management? Stock ECU plus Lantank's MAF? Miles on motor? Miles on turbo? Do you tow a lot or have it in constant boost?? (I do about 3k - 4k a year of 4,000 - 6,000 lb boat towing. What about head gasket?
This might warrant another dyno run.
Currently running stock ECU with stock MAF (I removed LT's MAF many moons ago to have him sleeve it and then totally forgot to send to him DOH! I should send that to him huh?).
Miles on motor: 182,000. Miles on turbo 107,000. I tow a trailer that would weigh about 3000 pounds full of firewood maybe 1/10th of the time and the other 9/10ths of the time I'm running it hard and happy without the trailer.
I'm running everything from 6,000 ft altitude to 12,800 ft altitude regularly. I only ever run warm when running really hard above 12K (warm for me is anything above 94C and it has never seen anything above 100C). Head gasket was PM'ed when rig hit 142K by Robbie aka PowderPig. AFR's with stock MAF are about 10.8 to 11.3 (depending on altitude) at WOT and I can't seem to lean that out so there's tons of headroom offered within the stock system. Hope that helps.
BTW, all the advice I've received and all the research I've researched is that the Unichip is best left out of the system totally.
damn .. that ( AFR's ) it's so good with all stock fuel system .. !
So not to be an ass but if the motor is still running rich at 10psi with the stock fueling system, why hasn't anyone turned up the boost to find the threshold?
And I know Turbocruiser said that it is still running rich at WOT, but hasn't it been discussed that the problem was never at WOT, and when it is at WOT it gets very rich? The problem has always been day to day driving under 3k rpm's when the system is in closed loop and trying to maintain a 14.7 AFR?
Has anyone introduced an O2 manipulator into the system to tell the computer it is running 14.7 in closed loop when it is really running 12? Just curious, seems like a lot of really smart people have been kicking this around for a while.
And I know Turbocruiser said that it is still running rich at WOT, but hasn't it been discussed that the problem was never at WOT, and when it is at WOT it gets very rich? The problem has always been day to day driving under 3k rpm's when the system is in closed loop and trying to maintain a 14.7 AFR?
Has anyone introduced an O2 manipulator into the system to tell the computer it is running 14.7 in closed loop when it is really running 12? Just curious, seems like a lot of really smart people have been kicking this around for a while.
I am not sure what kind of timing the 1FZFE runs, I think I remember reading somewhere that you mechanically adjust to 3* and then the computer adjusts on the fly. Tapage are you concerned that the computer would advance too much timing? Do we know under what conditions it advances timing? Does it retard if any knock is detected?
I have a MAF manipulator that I plan on using to install larger injectors.
I think that doing so will extend closed loop operation during boosted times. If that is the case I then want to try a O2 manipulator to do as you suggest and trick the ECU into managing the AFRs at 12.3
Not sure if that is how things will go but it is my plan at this point.
Not sure if I will be ready to try it out in a timely fashion but if so, I will let you know if the O2 manipulator works. I was just going to push to the max of the stock fueling system with a supra pump, and possibly an upgraded FPR. Possibly a 7th injector.
I wasn't thinking about larger injectors, what size are you going with? Are they same type as Supra injectors of the same time frame? Have you thought about just changing the size of your MAF housing? for example going to a 20% increase in MAF housing area and a 20% increase in injector size? I haven't really thought this through or done any math, but increasing the injector size the pulse width would stay the same and you would flow more fuel to match the extra air. Then using the O2 manipulator to think it is at 14.7 while it is at 12?
I wasn't thinking about larger injectors, what size are you going with? Are they same type as Supra injectors of the same time frame? Have you thought about just changing the size of your MAF housing? for example going to a 20% increase in MAF housing area and a 20% increase in injector size? I haven't really thought this through or done any math, but increasing the injector size the pulse width would stay the same and you would flow more fuel to match the extra air. Then using the O2 manipulator to think it is at 14.7 while it is at 12?
I got a set of WRX blues. They are high impedance, the same physical size and will drop right in.
The problem with enlarging the bore of the MAF is whether or not the sensor can read the lower air flow it would then see at idle. And then if it would yield a linear signal matched to the air flow.
With those running my MAF on boosted trucks we do see the sensor delivering a consistent signal throughout the operating range so using the MAF manipulator is pretty much a given as far as it working. You then would also be able to manipulate the signal during WOT to hopefully pull out some of the excess fuel the stock system likes to add.
The problem with enlarging the bore of the MAF is whether or not the sensor can read the lower air flow it would then see at idle. And then if it would yield a linear signal matched to the air flow.
With those running my MAF on boosted trucks we do see the sensor delivering a consistent signal throughout the operating range so using the MAF manipulator is pretty much a given as far as it working. You then would also be able to manipulate the signal during WOT to hopefully pull out some of the excess fuel the stock system likes to add.
Ok sounds good, I am guessing that the MAF sensor is a 5v signal. On a turbo'd truck how close to the max 5v's are you seeing? On my other car, I had to increase the housing size of the MAF about 20% so that it wouldn't max the signal, I guess if you are using the MAF modulator though it doesn't really matter. I would love to see someone crack the code to more boost.
here is where I'm going .. for us heat it's huge problem as well as gas quality .. 95 that isn't 95 under our outside temp conditions .. and under load we need to use kind of water / alcohol injection to help there ..
Nothing wrong with using a water/meth injection. I used it on my Supra for years with no issues and was able to run high boost on pump gas with it in 50/50 form. I may try it on the LX when I boost it before I go though to cost of a Water/Air set-up.
I used to have water/alcohol in my 2JZ too but that was factory turbo engine and having the possibilities of play with timing much more efficient make world of difference for us
Sent from my GT-N7000 using IH8MUD
Sent from my GT-N7000 using IH8MUD
I agree to get full benifit out of the w/m you need to have controle of the timing. But the w/m its self will cool the charge and act as a detonation deterrent with out any adjustment to the timing. They key will be selecting the correct size nozzle to prevent over use of it. I found on my 2jz with big turbo and boost that i would loose about 50whp just turning the system on but i was able to at 10psi more and go from 14deg at 4500rpm to 18deg with no det. The combination of the two netted 160whp still on 94oct gas.
It will for sure take tweeking and tuning (pressure on and max flow point) but its very doable and effective when set up right.
My hope is with water/meth i can run reg 87oct gas and have no issues with det. This will keep the system simple and effective, it will also reduce the risk of full boost part throttle on hills and so on when the ecu is trying to keep the afr at 14:1.