New turbo! Couple questions...
- Thread starter C.bowles2
- Start date
Hey guys what would be good over size injectors for the 68mm stg2r? Im on stock injectors and stock cp3. Kinda worried because i have 230k miles on them. Everything is running great but id hate to have a costly failure. My question is when the cp3 goes will it wipe out the injectors like the cp4 will?? Also worried about an injector sticking and burning a piston. Now heres the deal im still on stock internals besides head studs. Dont wanna do damage that way either
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Are you ever going to want to go past stock bottom end...if so what is your hp goal?
X2
If you're going to build the motor in the long run then yes, look at larger injectors but it depends on your goals/what you use the pickup for.
If you're not going to build the motor then I'd leave it.
Yellowchevy
Ideally id want to build it one day and im never satisfied haha but i dont know if my wallet will handle it. But id like to see over 600hp at the rear wheels. Im not sure if im there yet or not. I need to get it dyno'd but id be happy with a fun street truck that im still able to daily drive and take to the track a couple times a year.
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U can push your stock inj to 600 if you have more than a stock CP3 and run really high rail pressure. I have a really good buddy that has an LB7 that he did an Exergy 10MM on bone stock inj and turbo. He dynowed 586 and ran 12.2 1/4 mi...CCSB, of course it wasn't real clean at that. He rights his own tunes and mine as well. An S475/stock or similar kit would get you to 600 quicker than a single.
A) can you afford injectors and do you want to?
If you can afford them, or want to, then hell yeah, get the injectors! You can push stock injectors, but at what cost...ya know...IMHO, you're going to want performance I jectors to hit that 600whp goal, and a super strong cp3 or bag o parts/sportaman pump/fleece cp3k
B) you got the bigger turbo... you're doing it, yourself and the money you spent on that, a HUGE disservice running stock injectors, PERIOD! A larger injector delivers more fuel at the proper moment in less time, they'll drive the turbine more efficiently and unleash the MOST potential, and more efficiently from idle to peak.
C) you've already addressed the age of your current equipment...so you're already thinking it...do it now, even if you just get a reman stock cp3, get it in there, and a set of 40's, then if you build it later, you can twin the cp3 and dial the system to the peak potential of the 40's and choose to go past that at a later date...
I'd get 40's if you didn't catch that...
I know I'll probably get bashed for saying that, cuz I swear Ive read guys can/are runnin 100's on stock motors, but they are enough for smooth and easy +700whp and at the chaeper pricepoint.
Edit:
Forgot to mention, NO, the CP3 doesn't trash the whole fuel system like the cp4, but I do believe it can trash a set of injectors?
Double edit:
I speak from experience with the injectors, going from stock turbo/stock inj to 4094/stock inj, to VGT72 stock inj to VGT72/60's and now DP stg2 3794/60's all on a stock cp3 but highly optimized fuel path and assisted fuel delivery
still stock engine, but lost one of those with 160k on the clock and after 40k of ignorant brutality and bliss, at a bitter cost...
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X2 What he said^^, definitely easier on your engine to go bigger Inj, even though you can tickle 600 with stock inj. I'd agree with the 40 or 45% idea they would be really nice for stock bottom end and would also give you the potential to do a lot more. I think 700 is being a little conservative as to what they will support, but its always good to be a little conservative!
X2 What he said^^, definitely easier on your engine to go bigger Inj, even though you can tickle 600 with stock inj. I'd agree with the 40 or 45% idea they would be really nice for stock bottom end and would also give you the potential to do a lot more. I think 700 is being a little conservative as to what they will support, but its always good to be a little conservative!
It is really conservative depending on the setup/elevation etc etc...but my thought is always longevity and making the parts and system as a whole work in an ideal efficiency zone in all parameters, hoping the end result is longevity...and by "smooth and easy +700" I'm thinking the duty cycle of the injector would be running smoewhere +/-1800us with less than or close to 22° timing? Im totally guessing, I dont know chit about tuning:angel: but something smooth and easy
definately not stressing the injection system and engine to sustainably attain 
Correct me if im wrong, but I have heard (from Monte at ATP) that switching between hiss and rumble or changing vane position too much can cause issues...or is this just in the situation of a stock LLY turbo
so that will help 
How would switching between a closed and open vein position cause damage? The ecm changes the vein position all the time. Just curious. I''ve got the lb7 idle on my truck.
Isn't the vanes constantly changing anyways? I don't believe it does cause any more issues than anything else.
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That's why I was unsure. I think he means in the situation of having two separate tunes, ex: DSP 1 and DSP 2 position, each having a different vane position setting and switching between the two.
I really dont know for sure, mine is set to the lb7 rumble, but I do hear it change constantly while im at red lights and stuff
I agree, it don't really make sense:banghead:. Generally I take Monte's word...what was his reasoning?
Edit:answered that while I was typing
Edit:answered that while I was typing
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It really shouldn't change constantly at the red light. The rumble come from low vein percentage. That opens the veins and allows for the lb7 sound. The way I set them up there isn't that problem.
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It isn't a true LB7 rumble if its constantly changing My tuner generally makes tune 1 & 5 have LB7 Rumble. When its idling the vanes stay right at 3% on those.
My tuner generally makes tune 1 & 5 have LB7 Rumble. When its idling the vanes stay right at 3% on those.
By constantly changing, I mean self testing I think. I hear it often but not just changing back and forth
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