I dont think Ive ever hit 4000 RPM. If I did, it didn't stutter.
Injector Swap 1FZE to WRX
- Thread starter sknyfrnchguy
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is this a stock MAF replacement or one of the SC MAFs tuned for the wrx injectors?
One of the oversize housings with a modern Toyota sensor. Supercharger is not installed yet. Wanted to make sure everything is running properly first.
Does it have the number 3920 machined into the side of it?
I don’t know. Where would I find the number? Do you have a pic?
It would be on the side and very visible. If it isn’t there then you should pull the WRX injectors and put the stock ones back in and fix the lean code.
Ok. It’s not on there. When mine went bad, it was the only one I could find in stock. The WRX injectors fixed the lean code. So I have no codes now. Just starts to run bad about 4000 RPM.
The oversized injectors didn’t fix anything. You need to put the stock injectors back in and then fix the lean code.
I am in Phoenix, so we do a lot of " CHEATS" to keep our rigs running cool so we can wheel all year round. I run an undersized water pump pulley to speed things up a bit. The TYC 1918 radiator seems to run the coolest for us, and it holds up well to lots of trail miles. We juice up the fan clutch quite a bit. I figured out how to run the original fan which is much better than the one supplied with the TRD kit. I did have the OEM pusher fan but I found a stronger Spal fan that fits well. I had to make my own mounting brackets for that. It only makes a noticeable difference while running low ground speed and low rpm.
Measuring fuel trims it was consistently lean due to the cams I’m using.
Cams shouldn't make a difference. The MAF sensor should read the air flow and adjust the base injector timing automatically and avoid the P0170 code.
Other engines I’ve cammed also required additional fuel but back to post 11.
The reason I restarted this thread was because of post number 10 where the poster had seemed to describe the same issue I’m having at 4000rpm. It looks like the poster hasn’t been on in a number of years but I was curious if anyone else had the same experience and what the solution was.
The reason I restarted this thread was because of post number 10 where the poster had seemed to describe the same issue I’m having at 4000rpm. It looks like the poster hasn’t been on in a number of years but I was curious if anyone else had the same experience and what the solution was.
Hey guys question for you all, I have also gone down this route with the wrx blues and an aftermarket maf housing (inner diameter 2.9") and MAF part # 22204-21010 hoping to achieve a bit more fuel under in order to run a few more lbs, turbo'd my 1fz back in November and could safely get 7psi with the stock injectors. Truck is undrivable with MAF 22204-21010, I've also tried 22204-22010 as I had one also. The truck stumbles starting around 2000 RPM and will stop climbing in RPMs and speed is hard to get above 35 mph. Load is at 100% even at idle which is 100% not correct. With the factory maf it runs and runs well but short and long term fuel trims throwing a too rich code as expected with the long term at times as much as -30%. Has anyone else had these issues? Attached is a photo from the torque pro app which I'm using to monitor things. Truck wasn't quite all the way warm yet when I screenshotted the image but hot or cold it is undrivable with the updated MAF sensors. I haven't done any hard diagnosing yet as my first child was born in November and have only had time to swap sensors around but was just wondering if anyone else had experience this. Thanks in advance!
You can’t just through in larger injectors and expect things to work properly. You have to compensate for them by altering the injector timing. This can be done a few different ways, I chose to design a MAF housing specifically tuned to the larger flow. This negates the need to have the system tuned. Other options are a stand alone ECU or MAF calibrator.
Pros and cons for each.
Pros and cons for each.
@landtank thanks for the response, I didn't just throw them in expecting them to work properly but I had more than one sensor on hand, both of which have been tossed around here on mud. Per this thread here I thought a housing of 2.89 works which is what mine measures out to but for some reason only the factory maf will let me accelerate without tons of stumbling and choking. I guess my next test is to make sure I'm getting good contact at all 5 of the pins on the maf.
Other updates while turboing include, kyosan supra fuel pump, new knock sensors, colder NGK spark plugs and wires.
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are you running WRX injectors on your truck?
Yes, wrx blues
Currently have the factory maf in place, I have tried maf 22204-21010 in a 2.89" housing with the wrx blues and the result is terrible
Attached photo is with 22010 and wrx blues barely touching the throttle. Load is 100% at idle
All I can say is that neither MAF is appropriate for those injectors. You aren't gaining anything as well. Look at the LTFT, -39.84. Non of what you are doing is making any sense and only causing problems.
One guy is running my scaled setup on his turbo with great results. But that has a tuned MAF for the WRX injectors.
One guy is running my scaled setup on his turbo with great results. But that has a tuned MAF for the WRX injectors.
"You aren't gaining anything as well."
Clearly... I'm trying to figure out the why
"Look at the LTFT, -39.84."
Right, it's way off. I could swap the factory injectors back in and run the 21010 like others are doing per the thread I linked above for the "ghetto MAF housing" but I'm guessing I'll have the same problem where load is through the roof at idle.
"One guy is running my scaled setup on his turbo with great results. But that has a tuned MAF for the WRX injectors."
So when are you going to have those back in stock?
Clearly... I'm trying to figure out the why
"Look at the LTFT, -39.84."
Right, it's way off. I could swap the factory injectors back in and run the 21010 like others are doing per the thread I linked above for the "ghetto MAF housing" but I'm guessing I'll have the same problem where load is through the roof at idle.
"One guy is running my scaled setup on his turbo with great results. But that has a tuned MAF for the WRX injectors."
So when are you going to have those back in stock?
I upgraded my fuel pump to a Walbro 460 and it was too much flow for the factory FPR which has a restrictor in the return fitting. This caused my AFR’s to run very rich. I replaced the factory FPR with a turbosmart adjustable and adjusted the fuel pressure down to factory specs, how much fuel does the Supra pump flow?
As Landtank said you can’t just fit bigger fuel injectors, most go with an aftermarket ecu to do this. I run 9psi boost with standard injectors with an upgraded fuel pump, 255l Denso pump now with no problems on standard ecu.