950cc injectors

[Ironnman]

Hey guys, my first post. I'm currently upgrading my injectors to 750 cc deatschwerk injectors. I had an opportunity to upgrade to 950 cc injectors free of cost.
I have a dual intake set up with selin translator and a jwt ecu i'm gonna have re-tuned once the injectors come in.
My question is do any of you have any experience running 950cc injectors? are those too big? will a normal idle be achievable with a tune or should I stick with 740s?
Sorry I've tried to research online but I can't find any info of anybody running 950cc injectors.

[NolimitZ32]

1. If your car is NA anything larger than stock 270cc is TOO BIG a useless waste of money and will very likely cause your car to run MUCH worse since it wont be able to control the amount of fuel well at the lower volumes.
2. Deatschwerks has been known to produce less then stellar re-drills with questionable performance. It's not just about the volume, its about the spray pattern and atomization as well.

Who is going around telling people that bigger injectors are better? This is like the 3rd or 4th post in under a month where NA folks have been asking about up-sizing injectors?

[Ironnman]

Sorry I forgot to mention. I have a TT and they were 740ccs. I was looking the dw injectors up for the last few days and people have been saying they’ve have some good results for them. I also wanted to try them since they had a 3 year warranty.

[NolimitZ32]

3 year warranty on injectors isn't going to do any good when you have to replace the engine, I AM NOT saying this WILL happen with DWs or any others just pointing out that you need to be mindful when leaning on such things as a 3 year INJECTOR warranty. DW, at least in the past have produced more than an allowable quantity of sub-par product, specifically sidefeed JECS based units, I have no experience with other brands. All that said DW is known for having great customer service and being proactive in resolving issues with their injectors but they wont replace an engine. My advice is spend the additional $200 and get some Nismo injectors, they are manufactured by JECS directly for NISMO, they are manufactured as 7400cc units not redrilled like DWs are (or at least used to be). Also what type of power are you chasing and what turbos are you running to warrant such big injectors?

[DCaff300ZX]

3 year warranty on injectors isn't going to do any good when you have to replace the engine, I AM NOT saying this WILL happen with DWs or any others just pointing out that you need to be mindful when leaning on such things as a 3 year INJECTOR warranty. DW, at least in the past have produced more than an allowable quantity of sub-par product, specifically sidefeed JECS based units, I have no experience with other brands. All that said DW is known for having great customer service and being proactive in resolving issues with their injectors but they wont replace an engine. My advice is spend the additional $200 and get some Nismo injectors, they are manufactured by JECS directly for NISMO, they are manufactured as 7400cc units not redrilled like DWs are (or at least used to be). Also what type of power are you chasing and what turbos are you running to warrant such big injectors?

Agreed, DW in the past had a LOT of issues and personally I will not deal with them.
Also, as mentioned your spray pattern and reliability of the injector are your two main concerns, plus of course that they will work with our engine. Extra injector cc are wasted beyond what the engine needs, so 700-800cc is probably the best range for 400+ HP builds with all of the supporting mods such as upgrade intake/smics, ECU, turbos/DP's, etc. I believe some Subie injectors are usable and personally I had Bosch 800cc units used with my build, it all comes down to the correct pattern and tuning that in through your AFC.

[evildky]

Just to ballpark the size question a bit. on a 6 cylinder, those 740's will supply enough fuel for over 700 WHP, if you run E85 closer to 500 WHP. 950's can support up to around 900 WHP, and if E85, closer to 700 WHP. So the question is what fuel are you running, and what kind of power are you aiming for? If you are sport 550 turbo's, the 740's are more than enough fuel even on E85. This math is all ballpark, you can look up and do the math yourself but it gets you in the neighborhood.

You want your injectors to be a little larger than you need for safety margin, but not a lot. The larger the injectors the shorter the injector pulse will be, ideally the injector pulse matches the time the intake valve spends open for the best chance to mix with the air completely.

[DCaff300ZX]

Just to ballpark the size question a bit. on a 6 cylinder, those 740's will supply enough fuel for over 700 WHP, if you run E85 closer to 500 WHP. 950's can support up to around 900 WHP, and if E85, closer to 700 WHP. So the question is what fuel are you running, and what kind of power are you aiming for? If you are sport 550 turbo's, the 740's are more than enough fuel even on E85. This math is all ballpark, you can look up and do the math yourself but it gets you in the neighborhood.

You want your injectors to be a little larger than you need for safety margin, but not a lot. The larger the injectors the shorter the injector pulse will be, ideally the injector pulse matches the time the intake valve spends open for the best chance to mix with the air completely.

Good stuff evildky, I forgot about the injector pulse part and how that's also a huge player in the injector game. When I had my work done the Subie injectors were judged just a tad too large at 850cc, and the 800's would work better for a short, correct-sized dosage as the valve opens.

[NolimitZ32]

I'm running EJ257 STI Yellow tops which are rated around 520cc, this will be my next upgrade (once the car is put back together). I've had to keep the boost down since I don't have enough headroom but otherwise they work great.

[zxFarside]

I run DW 740s. They work good for my setup, and have great drivability. I make somewhere in the low 400s.

950s can drive normal if they are tuned right.

[Ironnman]

I really appreciate all the replies, it's been a great help. I'm trying to achieve around 450-500 hp and my next upgrade are going to be my turbos, down pipes and test pipes. One of my injectors crapped out
so that's what warranted the injector upgrade and since I had everything apart, I just upgraded to a dual intake set up. I'm eventually going to upgrade everything that's why I'm shooting for 740s so I wouldn't have upgrade a second time
but since they offered a free upgrade, I wanted to get your guys' opinions.

[NolimitZ32]

740s will handle any T25 frame turbo unless you're planning to run e85, if you're planning on running e85 you're likely going to need much larger than 950. For 500chp you can run 620s safely.