GT25R Max boost on stock fuel???

[Danner]

Just finished the swap. This is on an s13 Red top. RWD. car is bpu. I have stock fuel accept for a walbro pump. I have injecters/rail/and Regulator in my room. Waiting for ECU tune to put those on.

I just need to know if 10psi is safe out of a gt25r on stock fuel system? I cannot get my hks actuator to boost any lower than this. Any help is appreciated

[drift freaq]

it will work with the upgraded fuel pump. you can always get air/fuel ratio meter to check as well so if you are lean you can install your spare parts. also put in a 300zx fuel filter if you have not yet. stock KA fuel filters bite on SR's

[Id-]

Originally Posted by drift freaq

it will work with the upgraded fuel pump. you can always get air/fuel ratio meter to check as well so if you are lean you can install your spare parts. also put in a 300zx fuel filter if you have not yet. stock KA fuel filters bite on SR's

umm dude; you DO realize that injectors can SEEM to run very rich at 100% duty cycle? Guess what happens when one of htem fails? KABOOM.... you just gave advice that could detonate someone's motor... you know what the difference between 12:1 and 13:1 is on a narrowband meter?


To the original author:

Do not listen to this guy's advice; its a good way to blow a motor... NEVER trust a narrowband O2 sensor when tuning... its only used by the ECU to keep a certain mixture during closed-loop operation (ie. cruising at part throttle)
Your ECU may have a fuel curve that is lean in certain spots... and running a large-volume turbo such as the GT25R, you take a big risk if you try to tune on the edge of the injectors... I say run like 8psi to be safe; then get it tuned... better safe than sorry

[Danner]

I Guess I'll try to lower the actuator setting somehow. Ive made a few little spikes to 10psi. but didnt stay under throttle for more than 2 seconds. no smoke. duty cycle was at high 70's low 80's.

[drift freaq]

Originally Posted by Id-

umm dude; you DO realize that injectors can SEEM to run very rich at 100% duty cycle? Guess what happens when one of htem fails? KABOOM.... you just gave advice that could detonate someone's motor... you know what the difference between 12:1 and 13:1 is on a narrowband meter?


To the original author:

Do not listen to this guy's advice; its a good way to blow a motor... NEVER trust a narrowband O2 sensor when tuning... its only used by the ECU to keep a certain mixture during closed-loop operation (ie. cruising at part throttle)
Your ECU may have a fuel curve that is lean in certain spots... and running a large-volume turbo such as the GT25R, you take a big risk if you try to tune on the edge of the injectors... I say run like 8psi to be safe; then get it tuned... better safe than sorry

dude do you even own or run a SR? the stock injectors are good to 12lbs before hitting maximum duty cycle 10lbs is not the edge for SR injectors.
before you go flaming me understand I am speaking from the knowledge of SR engines do you have expernce with SR's? as far as a air fuel ratio meter goes on a SR its a god send. Oh ya and the GT25R is not that large a volume turbo its capable of around 325hp max.

Oh ya know I see in your sig you don't own a SR never have and are turboing a KA for the first time well mister newbie know it all SR's have different injectors than KA's i.e. 370cc vs KA 270cc. they are nowhere near max duty cycle at 10lbs boost in fact you can run 10lbs boost on them all day long and not have air fuel problems. Once you owned several turbo engines and played with several more you can come out and try to diss my advice until then STFU!!!! I Know what the hell advice I am giving or I would not give it you idgit!!!

[Danner]

Im not judging your knowledge on sr's. But you are wrong on the gt25r maxing 325hp. Ive seen them make close to 400wheel. I probably am pushing the stock 370cc injecters though. my turbo is pushing way more cfm's than the stock one does. So 10psi may be equal or equivalent to max duty cycle on sr's. psi is psi, but what matters is the volume of the air being pushed per square inch.

[msaskin]

Originally Posted by drift freaq

dude do you even own or run a SR? the stock injectors are good to 12lbs before hitting maximum duty cycle 10lbs is not the edge for SR injectors.
before you go flaming me understand I am speaking from the knowledge of SR engines do you have expernce with SR's? as far as a air fuel ratio meter goes on a SR its a god send. Oh ya and the GT25R is not that large a volume turbo its capable of around 325hp max.

Oh ya know I see in your sig you don't own a SR never have and are turboing a KA for the first time well mister newbie know it all SR's have different injectors than KA's i.e. 370cc vs KA 270cc. they are nowhere near max duty cycle at 10lbs boost in fact you can run 10lbs boost on them all day long and not have air fuel problems. Once you owned several turbo engines and played with several more you can come out and try to diss my advice until then STFU!!!! I Know what the hell advice I am giving or I would not give it you idgit!!!

Wow...you are a complete idiot.

air/fuel meter a godsend? Please. The stock o2 sensor and autometer blinky light gauge you're probably running tell me about as much information about my engine as the clock in the gauge cluster does. Tune with a wideband o2 or don't bother tuning at all.

10psi on stock injectors? Only with the stock turbo. I can tell you with my GT25R I was at 85-90% IDC's @ 8psi. how do I know this? Logging with my AEM. I ran 740's for my 25R, just put the stock ones in to do a bit of testing. (Danner, this is some info for you )

Also, 325rwhp max with a 25R? not really. The .64 a/r will put down 350-360rwhp depending on other mods and tuning, and the .86 a/r will put down close to 400rwhp as proven on multiple cars.

Next time you should do some research of your own and not just spew out the first (wrong) answer that comes to your head.

~matt

[Muzzy]

yea kook...a GT25R and a T25 are so much more different!! a GT25R might as well be a Big T28. cuz i know its bigger and flows more then a S15 T28. thats y they run 480s. bigger turbo...bigger injectors.
i wont run past .85bar cuz at .9bar (12.5psi) im hittin 98% injector duty. so i stay at .8 when i need to squirt(fast driving) and race. i only run .6 daily...yea u all say ".6..i run 12psi daily" i can to but thas jus stupid i think...im askin 4 trouble if i do that. not much can beat me at .6bar and its good enough for me to squirt through traffic effectively.

[Bradman123]

so how many pounds should he be running then...less then 8? i was thinkin about upgrading the gt25r but running on stock fuel(with exception of the walbro) until i could afford tuning and fuel. i was going to do this cuz i think my turbo is on its way out.

[Muzzy]

well if i have a way to monitor your injector duty u can get an idea of how safe to run. My AVC-R tells me my injector duty so thas how i came to the figure i did.

[msaskin]

Originally Posted by Bradman123

so how many pounds should he be running then...less then 8? i was thinkin about upgrading the gt25r but running on stock fuel(with exception of the walbro) until i could afford tuning and fuel. i was going to do this cuz i think my turbo is on its way out.

I have to preface this with a warning: running an upgraded turbo (Especially one as big as a GT25R) is a bad idea on stock fuel. One boost spike (or weak fuel pump, or dying injector, etc...) and you will kill off your motor.

That said, the numbers I logged on stock injectors show 8-9psi to be about the maximum you really want to run.

~matt

[drift freaq]

Originally Posted by msaskin

I have to preface this with a warning: running an upgraded turbo (Especially one as big as a GT25R) is a bad idea on stock fuel. One boost spike (or weak fuel pump, or dying injector, etc...) and you will kill off your motor.

That said, the numbers I logged on stock injectors show 8-9psi to be about the maximum you really want to run.

~matt

well punk ass he is not running stock fuel he is running a walbro pump which for your info happens to run to rich for a stock sr .Oh ya show me the dyno charts for your supposed 400whp on a Gt25r hahahhahha stick it up your ass motherfucker . with that fuel pump my advice was sound.
I stand by what I said not what was construed out of what I said with that fuel pump he is safe at 10 psi with that fuel pump!!! now the rest of you jack ass name calling fucks can go eat turkey.

[Id-]

Originally Posted by drift freaq

before you go flaming me understand I am speaking from the knowledge of SR engines do you have expernce with SR's? as far as a air fuel ratio meter goes on a SR its a god send. Oh ya and the GT25R is not that large a volume turbo its capable of around 325hp max.

experience with SRs? How bout experience with turbocars in general since they all work on the same principles? Since I've seen GT25R dynos over at FA showing 350rwhp consistently on untuned cars, I think that shows that you dont know what you're talking about... SR or not... the SR isnt any different from another turbo motor... if you think you know something more about it than someone else here, please post your knowledge... but so far you're just posting BS that shouldnt be listened to by avid readers that are actually trying to learn something...

Originally Posted by drift freaq

well punk ass he is not running stock fuel he is running a walbro pump which for your info happens to run to rich for a stock sr .Oh ya show me the dyno charts for your supposed 400whp on a Gt25r hahahhahha stick it up your ass motherfucker . with that fuel pump my advice was sound.
I stand by what I said not what was construed out of what I said with that fuel pump he is safe at 10 psi with that fuel pump!!! now the rest of you jack ass name calling fucks can go eat turkey.

jeez man way to give thread-lock fodder for a mod; bet you'll end up pink...

for the record; go do some RESEARCH!!!! injectors dont max out at a preset boost level... a bigger fuel pump wont do anything for the injectors... the fuel pressure is the same, therefore the injector flow is the same (and their max flow) is the SAME... 370s are 370s are 370s...
if you toss on a GT25R and run 12psi you WILL blow the motor pretty quick...

you sound like some of the other guys around here taht claim KA ring lands blow up at 10psi...

as for others on this thread; this guy is prolly worthless to spend time correcting; doesnt listen to anyone when he's proven wrong; seen it in plenty of other threads... i've pretty much given up... if there's something to learn from all this: you wont learn much by reading magazines and watching fast and the curious

[street assassin]

Wow, all this fighting over a simple question. My advice all be it very simple. Dont upgrade one thing at a time. You must make upgrades evenly across the board to supportr each other. So, get you fuel and ignnition to a known/proven good point before you go boosting that "big" turbo.

Its like having a 500whp car with stock suspension and brakes. Its useless.

And this is a turbo Im looking at. Yes, its a street driven car, and I will spool it by 3500rpm.
Compressor Specifications:
-T04R 67mm compressor wheel with a max flow rate of 75 lb/min
-0.70AR T04S compressor housing
-Good to 720 whp.

Turbine Specifications:
-p trim turbine wheel
-0.68 AR tangential housing
-v-band turbine discharge

CHRA Specifications:
-360 degree thrust bearing standard.
-Oil cooled&lubricated center section.

[Id-]

Originally Posted by street assassin

Wow, all this fighting over a simple question. My advice all be it very simple. Dont upgrade one thing at a time. You must make upgrades evenly across the board to supportr each other. So, get you fuel and ignnition to a known/proven good point before you go boosting that "big" turbo.

Its like having a 500whp car with stock suspension and brakes. Its useless.

And this is a turbo Im looking at. Yes, its a street driven car, and I will spool it by 3500rpm.
Compressor Specifications:
-T04R 67mm compressor wheel with a max flow rate of 75 lb/min
-0.70AR T04S compressor housing
-Good to 720 whp.

Turbine Specifications:
-p trim turbine wheel
-0.68 AR tangential housing
-v-band turbine discharge

CHRA Specifications:
-360 degree thrust bearing standard.
-Oil cooled&lubricated center section.

I dont think there's fighting over a simple question; its a little bit more complicated than that... but anyway
You definitely hit the nail on the head as far as even upgrading; but you're wrong about having to upgrade the suspension and brakes to compensate for power increases...
suspension is something to upgrade once, MAYBE twice... and thats it... brakes are just once... this isnt gran turismo; barring the 240sx, there are a lot of cars that can get by on 500rwhp, stock brakes and stock suspension...
2nd and 3rd gen RX-7, 2nd gen MR2 Turbo, MKIII and MKIV Supra Turbo, even the Z32TT

You putting that T04R on a Supra? thats a pretty sweet turbo; I've seen a lot of 2jz guys running 67mm turbos... but even on them you wont get spoolup at 3500rpms; more like 4000-4500... and this is on a 3 liter...
if you're doing this on a SR or KA and expecting that, you're crazy, because it wont happen unless your running nitrous; and even then i'd bet it wouldnt happen
67mm turbo on a KA, I'd expect to have full boost by around 5500rpms os so depending on tune and things... but you WILL NOT get spoolup at 3500rpms on any japanese 4 cylinder without nitrous...

[sr240mike]

I guess too many 240 owners are too cheap to do anything the right way. Brakes and suspension "should" come before dropping 350hp into it. Drift Freaq I dont see how you could post that info with over 1000 posts. Even with the stock regulator not much extra fuel gets through with a 255lph pump. How do i know, because I tried it with a fuel pressure gauge!!! mmmm the turkey was good too.

[street assassin]

Originally Posted by Id-

I dont think there's fighting over a simple question; its a little bit more complicated than that... but anyway
You definitely hit the nail on the head as far as even upgrading; but you're wrong about having to upgrade the suspension and brakes to compensate for power increases...
suspension is something to upgrade once, MAYBE twice... and thats it... brakes are just once... this isnt gran turismo; barring the 240sx, there are a lot of cars that can get by on 500rwhp, stock brakes and stock suspension...
2nd and 3rd gen RX-7, 2nd gen MR2 Turbo, MKIII and MKIV Supra Turbo, even the Z32TT

You putting that T04R on a Supra? thats a pretty sweet turbo; I've seen a lot of 2jz guys running 67mm turbos... but even on them you wont get spoolup at 3500rpms; more like 4000-4500... and this is on a 3 liter...
if you're doing this on a SR or KA and expecting that, you're crazy, because it wont happen unless your running nitrous; and even then i'd bet it wouldnt happen
67mm turbo on a KA, I'd expect to have full boost by around 5500rpms os so depending on tune and things... but you WILL NOT get spoolup at 3500rpms on any japanese 4 cylinder without nitrous...

Its not a must to upgrade suspension and brakes. Thats not the point. The point was how can you put was that you need to upgrade the suspension to put the power down. Yes, upgrade the drive line too. Face it, stock brakes wont slow you down like they should with the added power you can abtain with a boosted powerplant. It is far to easy to double the amount of power. If not tripple it compared to an NA motor.

And, no, I do not own a Supra, nor any other Japanese 4 cylinder.

[drift freaq]

Originally Posted by Id-

experience with SRs? How bout experience with turbocars in general since they all work on the same principles? Since I've seen GT25R dynos over at FA showing 350rwhp consistently on untuned cars, I think that shows that you dont know what you're talking about... SR or not... the SR isnt any different from another turbo motor... if you think you know something more about it than someone else here, please post your knowledge... but so far you're just posting BS that shouldnt be listened to by avid readers that are actually trying to learn something...




jeez man way to give thread-lock fodder for a mod; bet you'll end up pink...

for the record; go do some RESEARCH!!!! injectors dont max out at a preset boost level... a bigger fuel pump wont do anything for the injectors... the fuel pressure is the same, therefore the injector flow is the same (and their max flow) is the SAME... 370s are 370s are 370s...
if you toss on a GT25R and run 12psi you WILL blow the motor pretty quick...

you sound like some of the other guys around here taht claim KA ring lands blow up at 10psi...

as for others on this thread; this guy is prolly worthless to spend time correcting; doesnt listen to anyone when he's proven wrong; seen it in plenty of other threads... i've pretty much given up... if there's something to learn from all this: you wont learn much by reading magazines and watching fast and the curious

dude you have your head so far up your ass you can't even read what I wrote. I said at 10 psi he was safe and guess what that is exactly the question he asked and guess what I am right about that. Having done it . I NEVER SAID BOOST 12 PSI!!! with that setup and only a upgraded fuel pump. I said he was safe at 10 psi. so you guys can make more horsepower with your GT25r 's great . You guys got so high on your own knowledge you forgot the basic question the guy asked.
I did not . In trying to make it clear to you guys what I said you assholes went off on your own describing how much horsepower you got and your mods. Get a life.
I was not wrong in the answer I gave him. He will not blow up his engine running 10 psi with that turbo and the walbro pump.
Does he need other fuel mods to run more boost ? Of course he does but he did not ask that question.
I do know what I am talking about and I answered his question. If you guys want to pump your egos by going off and not really answering his question but dissing on people who do fine by me.
Fact is I answered his question with a correct answer. I did not go beyond that because he did not ask for it. Oh excuse me I should have told that to run 12 psi he needs more upgrades. fuck me. He did not ask for that advice.

P.S. I only came back to this thread because one of you jackasses decided you wanted to rate me as not having enough knowledge to speak. I have more knowledge and years in my pinkie than most of you fuckheads have in your fucking oh smart heads

[Jeff240sx]

Originally Posted by Id-

umm dude; you DO realize that injectors can SEEM to run very rich at 100% duty cycle? Guess what happens when one of htem fails? KABOOM.... you just gave advice that could detonate someone's motor... you know what the difference between 12:1 and 13:1 is on a narrowband meter?


To the original author:

Do not listen to this guy's advice; its a good way to blow a motor... NEVER trust a narrowband O2 sensor when tuning... its only used by the ECU to keep a certain mixture during closed-loop operation (ie. cruising at part throttle)
Your ECU may have a fuel curve that is lean in certain spots... and running a large-volume turbo such as the GT25R, you take a big risk if you try to tune on the edge of the injectors... I say run like 8psi to be safe; then get it tuned... better safe than sorry

100% duty cycle is not possible. The injector will go static, and burn up. Even 95%, sometimes less, will cause the injector to go static. When a static injector fails, it never closes again. No kaboom in this situation.
Next up is that the a/f gauge does something, because the O2 sensor is a 0-1v unit. This gives 10 precise points to move the gauge to. The blinky light gauge is worthless, but assuming that all air/fuel gauges are blinky light style shows a lack of knowledge. Look at a GReddy gauge. It has a needle and numbers. A wideband is 0-5v, and shows the same thing, just more accurate. However, narrow-band gauges can show a trip to 11:1 or 13:1, pointing towards an issue in progress. A wideband will show 12.6:1 due to higher resolution. There is also a middleground. Some companies (GReddy is one I think) give a higher resolution 0-2.5v gauge and sensor.

Stock SR motors are good to 15psi on stock injectors on the stock turbo, about 270hp. And a gt25r isn't a much larger turbo. It's just ball bearing. 10psi on it will be fine. We're not talking t61 here...
Finally, know what the hell you're talking about before making snap judgements, insults, and giving members bad reputation.
-Jeff