?'s on 1jz (bpu mods, 2jz turbos on 1jz, & single turbo on stock ecu?)
07-22-12, 01:10 AM
#1
Driver School Candidate
Thread Starter
Join Date: Jul 2012
Location: FL
Posts: 4
Likes: 0
Received 0 Likes
on
0 Posts
?'s on 1jz (bpu mods, 2jz turbos on 1jz, & single turbo on stock ecu?)
I'm about to start modding/working on my car soon and I had a couple questions since this is my 1st time modding a turbo motor.
I plan on sticking with these mods & the stock ecu for awhile, but will the following mods be ok? Anything else you guys would recommend?
3" Exhaust
FMIC
Boost Controller
SAFC2
Boost Cut
Fuel Cut
Stage 2 Clutch & resurfaced flywheel
I also have an aeromotive fuel regulator kit & hks dli but didn't know if I could or should use them
And what are the pros & cons of swapping 2jz turbos onto the 1jz? Some say its a waste of time, but why? I have a friend who can fabricate stuff for me if that is the problem.
I've also seen people throwing options of swapping turbos with twin t28's off a nissan, or td04's from a subaru. Has anyone done this and what are the pros/cons of this?
I plan on sticking with these mods & the stock ecu for awhile, but will the following mods be ok? Anything else you guys would recommend?
3" Exhaust
FMIC
Boost Controller
SAFC2
Boost Cut
Fuel Cut
Stage 2 Clutch & resurfaced flywheel
I also have an aeromotive fuel regulator kit & hks dli but didn't know if I could or should use them
And what are the pros & cons of swapping 2jz turbos onto the 1jz? Some say its a waste of time, but why? I have a friend who can fabricate stuff for me if that is the problem.
I've also seen people throwing options of swapping turbos with twin t28's off a nissan, or td04's from a subaru. Has anyone done this and what are the pros/cons of this?
07-22-12, 06:57 AM
#4
3" Exhaust
FMIC
Boost Controller
SAFC2
550cc injectors
AFPR
Stage 2 Clutch & resurfaced flywheel
Boost cut (which is the same as fuel cut, unless you're talking about the speed limiter) basically clamps the voltage at a level below what the ECU cuts at and just leaves it there. This is not ideal since with a SAFC you really have no way of tuning once the voltage is clamped. You just tune it rich at that point and hope you're lucky and don't lean out at one of the most critical points in the powerband. I suggest instead doing big injectors. By using large injectors and tuning down with SAFC, you will artificially skew the MAP sensor range and allow yourself to hit a higher boost level. The FPR is a great way to fine tune the base fuel pressure so that the ECU has no issues idling.
07-22-12, 01:30 PM
#5
Driver School Candidate
Thread Starter
Join Date: Jul 2012
Location: FL
Posts: 4
Likes: 0
Received 0 Likes
on
0 Posts
If i go with a medium size single turbo, what are the pros/cons of doing so with a stock ecu?
07-22-12, 01:38 PM
#6
Driver School Candidate
Thread Starter
Join Date: Jul 2012
Location: FL
Posts: 4
Likes: 0
Received 0 Likes
on
0 Posts
That's a solid setup but I would suggest your list looks more like this;
3" Exhaust
FMIC
Boost Controller
SAFC2
550cc injectors
AFPR
Stage 2 Clutch & resurfaced flywheel
Boost cut (which is the same as fuel cut, unless you're talking about the speed limiter) basically clamps the voltage at a level below what the ECU cuts at and just leaves it there. This is not ideal since with a SAFC you really have no way of tuning once the voltage is clamped. You just tune it rich at that point and hope you're lucky and don't lean out at one of the most critical points in the powerband. I suggest instead doing big injectors. By using large injectors and tuning down with SAFC, you will artificially skew the MAP sensor range and allow yourself to hit a higher boost level. The FPR is a great way to fine tune the base fuel pressure so that the ECU has no issues idling.
3" Exhaust
FMIC
Boost Controller
SAFC2
550cc injectors
AFPR
Stage 2 Clutch & resurfaced flywheel
Boost cut (which is the same as fuel cut, unless you're talking about the speed limiter) basically clamps the voltage at a level below what the ECU cuts at and just leaves it there. This is not ideal since with a SAFC you really have no way of tuning once the voltage is clamped. You just tune it rich at that point and hope you're lucky and don't lean out at one of the most critical points in the powerband. I suggest instead doing big injectors. By using large injectors and tuning down with SAFC, you will artificially skew the MAP sensor range and allow yourself to hit a higher boost level. The FPR is a great way to fine tune the base fuel pressure so that the ECU has no issues idling.
So if im using the stock 1jz turbos, which limit is ab 13-15psi correct? Won't I damage the turbos if I hit a higher boost level? What ab swapping with 2j turbos?
And i found a medium sized single turbo in my storage unit.... if I use the bigger injectors and tuning down with the safc like you said, I wont damage the ECU or anything? How would the car drive/respond? How would the overall reliability be?
Last edited by kwbeach; 07-22-12 at 01:52 PM.
07-22-12, 04:29 PM
#7
Running a larger turbo WITHOUT bigger injectors can be VERY damaging.
Stock twins can be run beyond 13-15psi. I ran mine @ 23psi for over a year. (Most would not recommend pushing them that hard but 18psi is still relatively safe)
I wouldn't spend money on either the Greddy or HKS unit since a SAFC + big injector combo replaces the FCD in function. Both the Greddy and HKS units are the same in role. The HKS cuts the voltage seen by the ECU by an adjustable percentage while the Greddy unit cuts the voltage seen by the ECU by limiting the max voltage. Both are flawed approaches IMHO.
I would need more info about your single turbo to make any predictions. Depending on size, you can lose horsepower and gain turbo response or,most likely, gain power but lose out on response.
The SAFC and big injectors just lets you safely run more boost and bigger turbos. It shouldn't alone cause any damage or extra wear on it's own. More boost is a different story...
Stock twins can be run beyond 13-15psi. I ran mine @ 23psi for over a year. (Most would not recommend pushing them that hard but 18psi is still relatively safe)
I wouldn't spend money on either the Greddy or HKS unit since a SAFC + big injector combo replaces the FCD in function. Both the Greddy and HKS units are the same in role. The HKS cuts the voltage seen by the ECU by an adjustable percentage while the Greddy unit cuts the voltage seen by the ECU by limiting the max voltage. Both are flawed approaches IMHO.
I would need more info about your single turbo to make any predictions. Depending on size, you can lose horsepower and gain turbo response or,most likely, gain power but lose out on response.
The SAFC and big injectors just lets you safely run more boost and bigger turbos. It shouldn't alone cause any damage or extra wear on it's own. More boost is a different story...
Trending Topics
07-22-12, 05:51 PM
#9
Lexus Test Driver
iTrader: (1)
Join Date: Dec 2008
Location: fl
Posts: 1,540
Likes: 0
Received 0 Likes
on
0 Posts
Running a larger turbo WITHOUT bigger injectors can be VERY damaging.
Stock twins can be run beyond 13-15psi. I ran mine @ 23psi for over a year. (Most would not recommend pushing them that hard but 18psi is still relatively safe)
I wouldn't spend money on either the Greddy or HKS unit since a SAFC + big injector combo replaces the FCD in function. Both the Greddy and HKS units are the same in role. The HKS cuts the voltage seen by the ECU by an adjustable percentage while the Greddy unit cuts the voltage seen by the ECU by limiting the max voltage. Both are flawed approaches IMHO.
I would need more info about your single turbo to make any predictions. Depending on size, you can lose horsepower and gain turbo response or,most likely, gain power but lose out on response.
The SAFC and big injectors just lets you safely run more boost and bigger turbos. It shouldn't alone cause any damage or extra wear on it's own. More boost is a different story...
Stock twins can be run beyond 13-15psi. I ran mine @ 23psi for over a year. (Most would not recommend pushing them that hard but 18psi is still relatively safe)
I wouldn't spend money on either the Greddy or HKS unit since a SAFC + big injector combo replaces the FCD in function. Both the Greddy and HKS units are the same in role. The HKS cuts the voltage seen by the ECU by an adjustable percentage while the Greddy unit cuts the voltage seen by the ECU by limiting the max voltage. Both are flawed approaches IMHO.
I would need more info about your single turbo to make any predictions. Depending on size, you can lose horsepower and gain turbo response or,most likely, gain power but lose out on response.
The SAFC and big injectors just lets you safely run more boost and bigger turbos. It shouldn't alone cause any damage or extra wear on it's own. More boost is a different story...
A SAFC or equivalent (fuel computer) typically will control <50% or >50% of stock fuel IE: 1JZ stock injector 380cc max comfortably controlled 680cc on a stock computer.
Regarding standalone Megasquirt 3 cost is around $1200 if you go this or any other standalone route then you will not need a fuel computer or FCD/BCC and will run virtually any injector size you would like.
GL.
07-22-12, 06:44 PM
#10
The factory computer is what controls the Boost / fuel cut and SAFC does not remove the cut you will still need a FCD to up the boost pressure.
A SAFC or equivalent (fuel computer) typically will control <50% or >50% of stock fuel IE: 1JZ stock injector 380cc max comfortably controlled 680cc on a stock computer.
Regarding standalone Megasquirt 3 cost is around $1200 if you go this or any other standalone route then you will not need a fuel computer or FCD/BCC and will run virtually any injector size you would like.
GL.
A SAFC or equivalent (fuel computer) typically will control <50% or >50% of stock fuel IE: 1JZ stock injector 380cc max comfortably controlled 680cc on a stock computer.
Regarding standalone Megasquirt 3 cost is around $1200 if you go this or any other standalone route then you will not need a fuel computer or FCD/BCC and will run virtually any injector size you would like.
GL.
That's why I recommended a AFPR which can pick up the slack so to speak and let the injector idle better with stock ECU. A 680cc can be used but you will need to drop base fuel pressure quite a bit which is kind of counterproductive when trying to run more fuel. I would NEVER tune past 35% + or - with an SAFC anyway. There is a pretty massive shift in ignition timing otherwise. I have been running 23psi on previous setup and 21psi currently without either a HKS FCD nor Greddy BCC. How did I manage this magic?
SAFC.
550cc injectors.
Base fuel dropped to 35psi.
Stock MAP sensor.
Why does this work?
The SAFC on these cars does not directly control injection. It controls MAP readings. It can artificially 'raise' the boost threshold if you pull or DECREASE the fuel map on the SAFC. This makes the ECU 'see' lower boost pressures via the MAP.
When I was on stock 370cc injectors with SAFC I ran into boost cut before the theoretical 2.3bar/~15psi magic number and only managed to see ~12psi before cut. Why? Because of other high flow mods (including 3" intercooler piping, 1100cfm front mount, 3" Y pipe off the turbo, 3.5" exhaust without cats, individual turbo intakes ) I was leaning out the stock injectors. I fixed this by cranking up the SAFC fuel map to make sure it wouldn't lean out. As a side effect, my fuel cut threshold was being met sooner.
07-22-12, 07:17 PM
#11
Lexus Test Driver
iTrader: (1)
Join Date: Dec 2008
Location: fl
Posts: 1,540
Likes: 0
Received 0 Likes
on
0 Posts
OEM 1JZ injectors are 370cc btw. Meaning by the 50% range it would be 555cc max That's why I recommended a AFPR which can pick up the slack so to speak and let the injector idle better with stock ECU. A 680cc can be used but you will need to drop base fuel pressure quite a bit which is kind of counterproductive when trying to run more fuel. I would NEVER tune past 35% + or - with an SAFC anyway. There is a pretty massive shift in ignition timing otherwise.
I have been running 23psi on previous setup and 21psi currently without either a HKS FCD nor Greddy BCC. How did I manage this magic?
SAFC.
550cc injectors.
Base fuel dropped to 35psi.
Stock MAP sensor.
Why does this work?
The SAFC on these cars does not directly control injection. It controls MAP readings. It can artificially 'raise' the boost threshold if you pull or DECREASE the fuel map on the SAFC. This makes the ECU 'see' lower boost pressures via the MAP.
When I was on stock 370cc injectors with SAFC I ran into boost cut before the theoretical 2.3bar/~15psi magic number and only managed to see ~12psi before cut. Why? Because of other high flow mods (including 3" intercooler piping, 1100cfm front mount, 3" Y pipe off the turbo, 3.5" exhaust without cats, individual turbo intakes ) I was leaning out the stock injectors. I fixed this by cranking up the SAFC fuel map to make sure it wouldn't lean out. As a side effect, my fuel cut threshold was being met sooner.
That's why I recommended a AFPR which can pick up the slack so to speak and let the injector idle better with stock ECU. A 680cc can be used but you will need to drop base fuel pressure quite a bit which is kind of counterproductive when trying to run more fuel. I would NEVER tune past 35% + or - with an SAFC anyway. There is a pretty massive shift in ignition timing otherwise. I have been running 23psi on previous setup and 21psi currently without either a HKS FCD nor Greddy BCC. How did I manage this magic?
SAFC.
550cc injectors.
Base fuel dropped to 35psi.
Stock MAP sensor.
Why does this work?
The SAFC on these cars does not directly control injection. It controls MAP readings. It can artificially 'raise' the boost threshold if you pull or DECREASE the fuel map on the SAFC. This makes the ECU 'see' lower boost pressures via the MAP.
When I was on stock 370cc injectors with SAFC I ran into boost cut before the theoretical 2.3bar/~15psi magic number and only managed to see ~12psi before cut. Why? Because of other high flow mods (including 3" intercooler piping, 1100cfm front mount, 3" Y pipe off the turbo, 3.5" exhaust without cats, individual turbo intakes ) I was leaning out the stock injectors. I fixed this by cranking up the SAFC fuel map to make sure it wouldn't lean out. As a side effect, my fuel cut threshold was being met sooner.
So the 2.3 bar you speak of is 15psi
really cause in my world 2.3bar is more like 33.35 psi but what do I know. I play at 29-31 psi virtually every weekend.Also just to set you straight I was running over 20psi on 1j twins with a AFC and FCD before you probably could drive.
Since when does an SAFC touch timing the curve in timing is limited by the thresholds in the stock ECU.
I on a AFC about 6-7+ yrs ago was controlling a set of precision 680cc injectors on a 1J with a 67mm single turbo at 30psi of boost and making 600 ish hp on 110octane and without the FCD could only get to between 12-14psi before the cut showed.
But I digress I am getting old and my memory apparently is clouded.
07-22-12, 07:28 PM
#12
So the 2.3 bar you speak of is 15psireally cause in my world 2.3bar is more like 33.35 psi but what do I know. I play at 29-31 psi virtually every weekend.
Also just to set you straight I was running over 20psi on 1j twins with a AFC and FCD before you probably could drive.
Since when does an SAFC touch timing the curve in timing is limited by the thresholds in the stock ECU.
I on a AFC about 6-7+ yrs ago was controlling a set of precision 680cc injectors on a 1J with a 67mm single turbo at 30psi of boost and making 600 ish hp on 110octane and without the FCD could only get to between 12-14psi before the cut showed.
But I digress I am getting old and my memory apparently is clouded.
really cause in my world 2.3bar is more like 33.35 psi but what do I know. I play at 29-31 psi virtually every weekend.Also just to set you straight I was running over 20psi on 1j twins with a AFC and FCD before you probably could drive.
Since when does an SAFC touch timing the curve in timing is limited by the thresholds in the stock ECU.
I on a AFC about 6-7+ yrs ago was controlling a set of precision 680cc injectors on a 1J with a 67mm single turbo at 30psi of boost and making 600 ish hp on 110octane and without the FCD could only get to between 12-14psi before the cut showed.
But I digress I am getting old and my memory apparently is clouded.
The OEM 2.3bar MAP will not let you get anywhere near 33psi. Fuel cut is well below that. Once the ECU sees x volts, it cuts out. Well below 2.3 bar of pressure. I agree.
SAFC does NOT have any control of timing. However it DOES affect timing through it's manipulation of MAP voltage. Like I said before, if you had the SAFC tuned DOWN to lower the amount of fuel, you wouldn't have hit the fuel cut as soon. It's still there. It's just proportionally shifted in relation to how much you fuel you pull.
I don't make 600HP any day of the week. I don't come close to maxing my 550's. However, I do have room with my fuel pressure still set pretty high, to pull fuel, which does raise the boost cut by tricking the ECU into seeing less MAP voltage.
07-22-12, 07:48 PM
#13
Lexus Test Driver
iTrader: (1)
Join Date: Dec 2008
Location: fl
Posts: 1,540
Likes: 0
Received 0 Likes
on
0 Posts
Whoaaa relax. Not trying to get into a pissing match here. Not doubting your credentials. I wish I could play at 31psi every weekend.
The OEM 2.3bar MAP will not let you get anywhere near 33psi. Fuel cut is well below that. Once the ECU sees x volts, it cuts out. Well below 2.3 bar of pressure. I agree.
SAFC does NOT have any control of timing. However it DOES affect timing through it's manipulation of MAP voltage. Like I said before, if you had the SAFC tuned DOWN to lower the amount of fuel, you wouldn't have hit the fuel cut as soon. It's still there. It's just proportionally shifted in relation to how much you fuel you pull.
I don't make 600HP any day of the week. I don't come close to maxing my 550's. However, I do have room with my fuel pressure still set pretty high, to pull fuel, which does raise the boost cut by tricking the ECU into seeing less MAP voltage.
The OEM 2.3bar MAP will not let you get anywhere near 33psi. Fuel cut is well below that. Once the ECU sees x volts, it cuts out. Well below 2.3 bar of pressure. I agree.
SAFC does NOT have any control of timing. However it DOES affect timing through it's manipulation of MAP voltage. Like I said before, if you had the SAFC tuned DOWN to lower the amount of fuel, you wouldn't have hit the fuel cut as soon. It's still there. It's just proportionally shifted in relation to how much you fuel you pull.
I don't make 600HP any day of the week. I don't come close to maxing my 550's. However, I do have room with my fuel pressure still set pretty high, to pull fuel, which does raise the boost cut by tricking the ECU into seeing less MAP voltage.
These have always been my experiences without a FCD on a AFC/SAFC/NEO.
07-22-12, 08:24 PM
#14
Point taken ^^^^ and neither am I but your explanation does not work out in several vehicles I've owned none of them have ever been able to move the boost cut you speak of moving just because I was using a larger injector and pulled fuel from the mix the boost cuts always hovered in the 12-14psi range depending on the IAT temp cooler more dense faster cut warmer air slower cut(higher).
These have always been my experiences without a FCD on a AFC/SAFC/NEO.
These have always been my experiences without a FCD on a AFC/SAFC/NEO.
I can't speak for other cars but because the recommended wiring for 1JZ's w/SAFC taps into MAP voltage (as per Apexi website, page 6 http://www.apexi-usa.com/manuals/ele...eo_diagram.pdf ) , it does not directly control the fuel injectors. Also, because the ECU uses this same MAP voltage reference for boost cut, the SAFC can skew this value percentage-wise. It's the same concept as running a 3bar MAP sensor to raise boost cut. You lower the voltage seen by the ECU. If you tune down an injector via SAFC because you are running too large of an injector for your setup, you are in effect lowering what the ECU will 'see' for boost pressure.
