CAN MY STOCK INJECTORS TAKE IT ?

[migsk8]

ok so im going to the track one last time before the winter and i had my mind set on a high 12. so anyways, i have a SR20 with stock injectors for the moment,and i have all the supporting goodies. i also have a 9:1 compression ratio. the boost controller that i have right now is a apexi avcr and it is really gay to set.im gonna set it to .95 bar aka 14psi and i have to set the duty%. i have to mes with it for lil bit. i think it has to be around 20%. anyways......i wanted to know if stock injectors will be fine for 14psi and a 9:1 compresion ratio? i only plan on putting it at 14psi if i need it and on this coming track day.....1/4 mile track that is

[240lab]

i dont think that your compression should affect you injector wise. ive heard that the stock injecters are only good to 12psi. my friend was getting some fuel cut at 16psi on stock turbo and injecters. just my 2 cents.

[migsk8]

i dont think that your compression should affect you injector wise. ive heard that the stock injecters are only good to 12psi. my friend was getting some fuel cut at 16psi on stock turbo and injecters. just my 2 cents.

i have 2 friends on 14psi and one on 15. i also had one on 17ps1 but his turbo blew lol. it took about 2 weeks for it to blow on 17psi. but anyways i was just making sure compression wont affect it. anyones elses detailed info would really help out

[Emperor_Tha]

are u still on the t25?

This is my afr in 3rd gear at 14psi

2000 0psi 14.12500. 10-12psi. 12.13000 14psi. 11.63500. 14psi. 11.84000. 14psi. 11.64500. 14psi. 11.05000-7000 14psi 10.6

300zx maf, t25 hks wastegate (10 psi) +mbc, afc neo on zero fuel trim adjustment, stock fpr, 255lph pump

On stock mafOn 14 psi 5000-7000 u are actually around 12.1-13.0 even when boost drop

2 different car before the tune. I think the maf is max out

[migsk8]

i dont think that your compression should affect you injector wise. ive heard that the stock injecters are only good to 12psi. my friend was getting some fuel cut at 16psi on stock turbo and injecters. just my 2 cents.

anybody actually sure on this subject ?

[migsk8]

are u still on the t25?This is my afr in 3rd gear at 14psi2000 0psi 14.12500. 10-12psi. 12.13000 14psi. 11.63500. 14psi. 11.84000. 14psi. 11.64500. 14psi. 11.05000-7000 14psi 10.6On 2 different car before the tune. Stock fpr, 255 pump300zx maf, t25 hks wastegate (10 psi) +mbc, afc neo on zero fuel trim adjustment, stock fpr, 255lph pumpOn stock mafOn 14 psi 5000-7000 u are actually around 12.1-13.0 even when boost drop

whats the 11.6-10.6 mean. what are those numbers ? wow you ran a 13.5 on 7 ps1? thats flippin awesome. i ran a 13.6 @ 105 last weekend. did you have slicks or anything? i just had some 255's (street tires)

[Hijacker]

His friend was getting a fuel cut at 16 psi, he was seeing detonation. The compressor efficiency is so horrid at that flow rate, that all he was doing was super heating the intake charge and his fuel mixture was pre-igniting. The stock turbo should NEVER go over 14. 14 straddles the compressor efficiency line, and will shorten the life span of the turbo.

EDIT: The numbers he posts next to the pressure rating are air/fuel ratios

[Emperor_Tha]

10.6 is my air/fuel ratio. That's rich. With my tune i'm doing 11.8 across the whole rpm which is pretty much perfect.

215/45/17 nitto neogen. Launch 6k no tire spin

[migsk8]

10.6 is my air/fuel ratio. That's rich. With my tune i'm doing 11.8 across the whole rpm which is pretty much perfect. 215/45/17 nitto neogen. Launch 6k no tire spin

lol wow my tires must suck ***, i launched at 3k with lil tire spin and when i launched at 3.5 all hell broke loose. i completely lost traction, it was more of a burnout lol. i dont understand how people launch at 5k+. did you like only use 20% throttle or something ? or did you floor it at 6k from a launch? when i left at 3k i used like 90% throttle.......(my apexi avc-r tells me throttle %) ok so prety much what im trying to ask is, if you had to guess what % was your gas down when you left at 6k ?

[migsk8]

10.6 is my air/fuel ratio. That's rich. With my tune i'm doing 11.8 across the whole rpm which is pretty much perfect. 215/45/17 nitto neogen. Launch 6k no tire spin

wait what? you have a tune?......i dont haha. i just have the basic upgrades, the z32 maf is not on the car either

[migsk8]

His friend was getting a fuel cut at 16 psi, he was seeing detonation. The compressor efficiency is so horrid at that flow rate, that all he was doing was super heating the intake charge and his fuel mixture was pre-igniting. The stock turbo should NEVER go over 14. 14 straddles the compressor efficiency line, and will shorten the life span of the turbo.EDIT: The numbers he posts next to the pressure rating are air/fuel ratios

yeah im not too worried about the turbo, i have t04b chillin in my room. but im only putting it at 14psi for that one day pretty much. or if i just happen to race an sti or something like that haha

[migsk8]

10.6 is my air/fuel ratio. That's rich. With my tune i'm doing 11.8 across the whole rpm which is pretty much perfect. 215/45/17 nitto neogen. Launch 6k no tire spin

crap i forgot to ask you, what is your duty % set on your boost controller when the car is on 14psi ?

[Tulsa_S-13]

Wow, you have an AVCR and you haven't even taken the time to program it yet?

To get the most out of it you need to set the duty cycle for rpm increments.

You need to get on google and try to find programming guides.

[jr_ss]

i dont think that your compression should affect you injector wise. ive heard that the stock injecters are only good to 12psi. my friend was getting some fuel cut at 16psi on stock turbo and injecters. just my 2 cents.

Having higher compression will change your whole AFR's through out the entire map... Running 14psi on your car is dumb, let alone a T25... Get it tuned and stop asking stupid questions once again. Search, you know that 370cc's aren't worth a ****...

[migsk8]

Having higher compression will change your whole AFR's through out the entire map... Running 14psi on your car is dumb, let alone a T25... Get it tuned and stop asking stupid questions once again. Search, you know that 370cc's aren't worth a ****...

im going by what the 2 other guys are saying.....not you. i have to leave for school in like 2 seconds, can anybody find a good website on how to program the avc-r. the manual sucks and the only website i found was to set it per gear. which i dont want. well im off to school. hopefully someone can help out

[240_SeX]

14psi w/o a tune? that sounds like something you would do, Do you understand that that is twice stock boost?

[migsk8]

14psi w/o a tune? that sounds like something you would do, Do you understand that that is twice stock boost?

are you really this dumb ? do you know how many people turn the boost up to 14 and the computer just adjust on its owns? people do it all day long. im not even joking. everyone that i know that has an SR has a boost controller and has at one point or another turned it up to 14.

[Emperor_Tha]

are you really this dumb ? do you know how many people turn the boost up to 14 and the computer just adjust on its owns? people do it all day long. im not even joking. everyone that i know that has an SR has a boost controller and has at one point or another turned it up to 14.

Get a wideband gauge it's the only way to see if it's safe to run 14psi on stock maf+ecu

I have afc tune two different car with s13 sr with t25 stock maf+ecu. I do not recommend running on 14psi becuz the stock ecu don't compensate welL and starts running lean on the higher rpm power band

[240life]

I do it I don't recomend driving all day like that cause you are close to maxing your fuel injectors,maf and turbo at that point. But for a race or fun you will be ok. I ran a completely stock set up like that and if I hadn't f'ed my catch can routing up the engine would still be running strong. good luck with your build

[jr_ss]

Listen, I may dog on you alot, but you seriously need to do some research on what you want or what you are building. Even though I dog on you, I still try to help out in the least amount of way possible. The only way to learn is doing it yourself, not having someone hand you all the answers.

Think about it this way, your stock engine is 8.5:1, running 7psi and 370cc's injectors. Lets say your 8.5:1 comp is a 4x4 box. By increasing the compression to 9:1, you've decreased the size of your box to a 3.5x3.5 and doubled the boost. Now you're cramming twice the amount of air into that box, but not compensating with fuel. This leads to pre-ignition and detonation. 370cc's cannot and will never flow enough to let it be safe. Even with your 4x4 box at 14psi you're running the risk of leaning out.

Sure, short bursts or a pass at the drag when the car is cooler is fine, but turning your turbo into a heat pump which at 14-15psi on the T25 you are doing, increases the risk of blowing something... Heat soak is a ***** and it will raise the temps in your engine the way you are running it.

And yes, people do raise the boost to 14psi, but usually it's on a stock compression ratio bottomend. You've increased the compression by .5 which makes it even more dangerous...

Sorry for the long post, but sometimes you don't think outside the box man and you can't expect everyone to hold your hand. Time to grow up and learn something...

[migsk8]

Listen, I may dog on you alot, but you seriously need to do some research on what you want or what you are building. Even though I dog on you, I still try to help out in the least amount of way possible. The only way to learn is doing it yourself, not having someone hand you all the answers.

Think about it this way, your stock engine is 8.5:1, running 7psi and 370cc's injectors. Lets say your 8.5:1 comp is a 4x4 box. By increasing the compression to 9:1, you've decreased the size of your box to a 3.5x3.5 and doubled the boost. Now you're cramming twice the amount of air into that box, but not compensating with fuel. This leads to pre-ignition and detonation. 370cc's cannot and will never flow enough to let it be safe. Even with your 4x4 box at 14psi you're running the risk of leaning out.

Sure, short bursts or a pass at the drag when the car is cooler is fine, but turning your turbo into a heat pump which at 14-15psi on the T25 you are doing, increases the risk of blowing something... Heat soak is a ***** and it will raise the temps in your engine the way you are running it.

And yes, people do raise the boost to 14psi, but usually it's on a stock compression ratio bottomend. You've increased the compression by .5 which makes it even more dangerous...

Sorry for the long post, but sometimes you don't think outside the box man and you can't expect everyone to hold your hand. Time to grow up and learn something...

ok ok ok, got it, point taken. well you said its ok to run 14psi at the track for one day correct? because i am REALLY REAllY TRYING TO RUN 12'S THAT DAY. IDC IF ITS A 12.9999999. THAT IS MY GOAL.WELL CRAP. what about 12 psi ?

[migsk8]

its possible !!!!! but do you think i can do it on 12 psi? will my extra compression compensate for those lost 2 psi of boost ?

http://www.dragtimes.com/Nissa....html

[jr_ss]

You're car at 9:1 and 7psi is going to be faster than a normal car at 8.5:1 and 7psi. I honestly wouldn't go over 10psi... It's your car, your money. If you want to risk blowing it up it's on you... Personally, I wouldn't be driving it how it is right now, but that's me.

[240_SeX]

Just tune the damn car, even if you run 7psi you are going to get spark knock because the ecu dosent know you have 9:1 comp. the knock sensor can retard timing, but only to a certial amount. spend the money, tune the car, or you will be starting over.

[migsk8]

You're car at 9:1 and 7psi is going to be faster than a normal car at 8.5:1 and 7psi. I honestly wouldn't go over 10psi... It's your car, your money. If you want to risk blowing it up it's on you... Personally, I wouldn't be driving it how it is right now, but that's me.

wait what? whats wrong with the car how it sits stock? you cant say its ugly cuz i haven't done anything to it. what gives?

[migsk8]

Just tune the damn car, even if you run 7psi you are going to get spark knock because the ecu dosent know you have 9:1 comp. the knock sensor can retard timing, but only to a certial amount. spend the money, tune the car, or you will be starting over.

p.s. my car is running just fine on .9 bar or about 13 psi. i ran the crap out of it while i was figuring out my boost controller on the highway and it seemed just fine. then i redlined it from 1st to 4th and everything runs perfect.

[s14s14s14]

so if you alredy ran it at 13 psi why ask?

[jr_ss]

I was talking about your untuned motor configuration....

[240_SeX]

p.s. my car is running just fine on .9 bar or about 13 psi. i ran the crap out of it while i was figuring out my boost controller on the highway and it seemed just fine. then i redlined it from 1st to 4th and everything runs perfect.

you cant always feel knock, all im saying is that if you keep doing what your doing it will blow up, its your car, do what you want. but after it blows up i want you to admit to your complete failure and leave this fourm forever. because i really dont want to scrool through 129 more threads on why this happeded.

[migsk8]

you cant always feel knock, all im saying is that if you keep doing what your doing it will blow up, its your car, do what you want. but after it blows up i want you to admit to your complete failure and leave this fourm forever. because i really dont want to scrool through 129 more threads on why this happeded.

haha you're funny, nah i can do what i want. oh yeah and i also talked to my local 3 shops to make sure thats its ok to turn up the boost, im going with what they say. its fine to turn up the boost if i want. its just a smaller space and bigger explosion. plus you are an idiot. im never even considering anything you ever say