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MAJJ
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Discussion Starter · #1 ·
Sorry if this was brought up before. I'm planning to get the Cobb v3 with a PROtune from Bren and also go with the Cobb big Sf intake, which claims +150whp with my current mp/exhaust (548whp/588tq).

I'm keeping the stock downpipes and I'm not planning to run e85 at all. At what whp/tq am I supposed to increase injectors to 750cc?

I did not go for a tune earlier because I'm worried about warranty and issues from my dealership. What have you guys done, is your dealership ok with the tunes or giving you headache? Appreciate the help.
 

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Now would be a great time, especially since your getting it protuned, but don't forget dp's will make a huge power difference with everything you have plus protune
 

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If you are tuned and have a power train failure you will likely not be covered. You can pretty easily max out the injectors with just bolt-ons.
 

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MAJJ
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Discussion Starter · #4 ·
I'm not planning to add downpipes yet. Too loud n smelly to be daily driven. So just with tune id have to go with larger injectors??

Have other had engine/drivetrain problems caused by just a tune?
 

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MAJJ
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Discussion Starter · #5 ·
Forgot to mention. Im not tracking the car yet or anytime soon. Daily driving street mainly and highway
 

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I'm not planning to add downpipes yet. Too loud n smelly to be daily driven. So just with tune id have to go with larger injectors??

Have other had engine/drivetrain problems caused by just a tune?
You could have your tuner limit the power so your injectors are not maxed, but I think I would rather be safe then sorry. By the way, you will not get 150 whp with those mods, maybe close to 50whp.
 

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You can pretty easily max out the injectors with just bolt-ons.
Very true, you can always go with a catted down pipe and catless mid pipe. I went this way while I was FBO E85 and you leave maybe 10-15hp on the table, but no gas smell and at full weight you still trap 136 +/-
 

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Something is up with that dyno if a stock DBA only put down 400 whp, they are around 450 or so. Regardless, you will not gain 150whp, does anyone disagree with me? Kind of weird that he would show you such a misleading comparison.

You could look at Cobb Tuning website for some more realistic numbers.
 

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GT-R pilot
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Their baseline is certainly low, but recall that not all dynos read the same, nor are they calibrated to do so. More information would be required.
 

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A related question from me is when do you need to go to bigger fuel pumps? Meaning, I'm definitely aware that an FBO car has to be tune-limited not to exceed stock injectors, but if you had 1050/1100cc injectors how far can you go on the stock pump(s)?

Thanks!
 

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A related question from me is when do you need to go to bigger fuel pumps? Meaning, I'm definitely aware that an FBO car has to be tune-limited not to exceed stock injectors, but if you had 1050/1100cc injectors how far can you go on the stock pump(s)?

Thanks!
I ran out of Injector at Midpipe/Tune only.

I HIGHLY recommend reading your datalog and looking at your Injector Duty Cycle. I was max'd out at 15 psi, so I ordered 3" intakes and 1050cc injectors and a protune. It drives smoother/cleaner and IDC is 60% at 15 psi.

As for pumps on stock turbo/pump the factory pump is just fine.

Upgraded turbo and or E85(Flex fuel) then you NEED fuel pumps.
 

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Sorry if this was brought up before. I'm planning to get the Cobb v3 with a PROtune from Bren and also go with the Cobb big Sf intake, which claims +150whp with my current mp/exhaust (548whp/588tq).

I'm keeping the stock downpipes and I'm not planning to run e85 at all. At what whp/tq am I supposed to increase injectors to 750cc?

I did not go for a tune earlier because I'm worried about warranty and issues from my dealership. What have you guys done, is your dealership ok with the tunes or giving you headache? Appreciate the help.
Also just talk to your tech at the dealership, each one is different. From my experience if you take care of them then they will take care of you.

PS get injectors.

Cooper
 

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GT-R pilot
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I ran out of Injector at Midpipe/Tune only.

I HIGHLY recommend reading your datalog and looking at your Injector Duty Cycle. I was max'd out at 15 psi, so I ordered 3" intakes and 1050cc injectors and a protune. It drives smoother/cleaner and IDC is 60% at 15 psi.

As for pumps on stock turbo/pump the factory pump is just fine.

Upgraded turbo and or E85(Flex fuel) then you NEED fuel pumps.
Thank you my friend! I appreciate it.
 

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I agree with the majority here,a 650HP (550WHP) package would include 1050cc injectors,midpipe (catless) 3" intakes + filters +tune but not the pumps. Injectors are an easy install as are the other parts. I`m not in the States but have had no problem with Nissan when the car has been in for a service. Then again i`ve had no problems either.
 

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MAJJ
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Discussion Starter · #16 ·
I see. So in that case i would have to consider injectors (750,950 or 100cc?) if i go with:

-Hks midpipe
-3" intake
-tune

Correct? Keeping stock dp's

Thank you guys for the great feedback!!!
 

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I see. So in that case i would have to consider injectors (750,950 or 100cc?) if i go with:

-Hks midpipe
-3" intake
-tune

Correct? Keeping stock dp's

Thank you guys for the great feedback!!!
Yes 1050cc Bosch injectors accompanied my 650HP package. Dp`s can be exchanged for catless it all depends on your inspection. More power with catless dp`s and catless midpipe. I still have catted dp`s to pass inspection. I could though do catless dp`s and catted midpipe (which is the best power option) if i wanted.
 

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You new guys should really start reading some of the posts on here and use Google to search for all this, it has been discussed a million times. A midpipe alone will max out your injectors. If you want to go higher than 15psi you will need them. Period.

I was tuning my own car with the excellent Access Tuner Race this past year and found this out first hand. I found that if I stayed at and under 16psi I was almost at 100% IDC! So the OTS Stage 2 maps are safe for stock injectors, so use that and don't bother with a Pro Tune until you are ready for injectors and other supporting mods!
 

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GT-R pilot
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Yup, I just cannot soak up the information fast enough!
 
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