I want to change my injectors from my stock vette injectors to 46lb fast injectors where do I adjust for the extra fuel at and how should I make the adjustments so that it runs properly? Also Im going to add a ported TB where do I need to make adjusments for the extra airflow etc at idle? Thanks.
For the injectors you need to have first the right clabiration for them and you can have them by having Greg DVD from Summitracing.com it will save you time .but i dont think so that its listed in hes DVD for the fast 46lb .
If you must have the shorter style, then I recommend that you sell those and purchase the LS7/LS3 factory 42# injectors, which you can get all the calibration data for them by opening an '06-'09 Z06 file. Those would be enough fuel for 500 to 525+ rwhp .
If you can run a taller injector, then the Ford Racing 42# injector is what I'd go with.and is enough fuel for approx. 625+ rwhp Actual. Greg Banish (eficalibrator) offers all the proper injector calibration data for both the Siemens 60 and the Ford Racing 42, via his training DVD that he sells through SummitRacing.
so you can go to engin - fuel control - general - Flow rate vs. KPA and hear is where you change for the new injectors .
What prompted you to purchase the Fast injectors blindly without first studying to determine if there were possible injector calibration on them (which there isn't, btw)??? You'll either have to rape your tune, or you'll need to buy injectors with proper calibration data on them (highly suggested).
Formerly known as RWTD
Toys: '22 Tesla Model S Plaid / '20 Chevy Duramax / ?20 Sea-Doo RXT-X (2)
They were suggested as the correct size for the application. Im going to a larger cam soon and also NOS and will be over the 500rwhp mark. The 60lb was not recommended due to the fact that there may be too much fuel at idle and 42lb was a little too low. Im sure that there wont be a problem for a good tuner to calibrate these injectors but i wanted to give it a crack myself if possible.Originally Posted by RWTD
So my current values are at 33 up to 36.24. Would I just need to adjust the numbers here to match the injector size? I believe stock is 33 or 36 cant remeber.
Don't take this as a knock, but you're definitely not educated in the realm of tuning, especially in regards to injector calibration.
First of all, I am a tuner (I'll let my credentials speak for my abilities). Second, I don't care if you're Jesus, without the proper injector calibration, you can NOT tune properly for an injector, regardless of what injector you're using.
Whomever told you that you'd have too much fuel at idle on the 60s hasn't a clue WTF they are talking about. The Siemens 60# (which actually flows over 70 on a GM) run perfectly everywhere, provided you have the proper injector calibration data. Going on, the Ford 42# actually flows 52.x at GM's 58 psi factory fuel pressure, which is MORE than what that FAST injector you have flows. Plus, we have ALL the proper injector calibration data on the injectors offered by Ford Racing (thanks to Greg Banish, aka eficalibrator here on the boards). See here:
http://www.hptuners.com/forum/showth...584#post185584
You'll need to get your hands on a copy of Greg Banish's GM Training DVD in order to get the correct values for your injectors. You can purchase it new from Summit here:
http://www.summitracing.com/parts/SME-DVD-1/
You may be able to find a used copy of it, as well, so feel free to search around.
Keep in mind, you are buying a great training tool in order to help you understand and learn the basics and intermediate levels of tuning, so don't scoff at the price.
Again, more reason I *highly* suggest you purchase Greg's training DVD. After reviewing it just once, you'll understand why it is so critical to have ALL the injector calibration data, NOT just the IFR values you're asking about above. You either want to RAPE your tune (no lube either), or you want to do it the correct way. It's your choice.
Regards,
James
Last edited by RWTD; 10-20-2009 at 05:43 PM.
Formerly known as RWTD
Toys: '22 Tesla Model S Plaid / '20 Chevy Duramax / ?20 Sea-Doo RXT-X (2)
I dont have a clue what Im doing thats why Im asking not just changing things. I want to learn. I can do simple stuff like change some timing or adjust my shift points but other than that Im asking questions to increase my knowledge. I guess this adjustment would be too hard for me to make on my own.
I dont exactly understand what you mean by raping my tune to adjust for the injectors. Are you saying that there are a lot of different parameters that need to be changed to make em work?
Thanks for the replies. Like I said Im new to this and want to learn as much as possible.
Yes sir, there's 5 various parameters that need to be modified in order to properly control the injectors. For your C6, those are:
Offset vs. Volts vs. VAC (or Offset vs. Press vs. IGNV on the '07+ Gen4 vehicles)
Flow Rate vs. KPA (or Flow Rate vs. Press on the '07+ Gen4 vehicles)
Short Pulse Limit
Short Pulse Adder
Min Injector Pulse
BTW, are you going to be running a dry shot or a wet shot of nitrous? If a wet shot, which I recommend, you'll only be using additional pump, not injector.
As for different injectors than your stockers, either the LS3/LS7 42# injector is recommended (since they are shorter, you'd have to have injector extenders if you're going to run your factory LS2 intake), or the Ford 42# ("green-top", the same injector that was the factory injector on the '99-'04 Lightning), which flows 52.x on a GM 4-bar (58 psi) system. On all motor, the LS3/LS7 42# injector is good to approx. 550 rwhp at 90% DC (duty cycle).
That's one of the reasons I recommend Greg's training programs (whether his training DVD, or his in-person classes). It's honestly more important than the tuning software, especially for individuals new to tuning (hell, even those who've been around for years).Thanks for the replies. Like I said Im new to this and want to learn as much as possible.
Last edited by RWTD; 10-20-2009 at 06:14 PM.
Formerly known as RWTD
Toys: '22 Tesla Model S Plaid / '20 Chevy Duramax / ?20 Sea-Doo RXT-X (2)
Alright well thats some valuable info. I appreciate it. Im going to be over 550 rwhp with the shot. I should be at about 470-480 with the new cam and with a 75-150 shot of nitrous that puts me over the limit of 550 with the ford 42# which is why I was told to use a 46# and i will still probably be around 85% DC. Im not sure if Im going to use wet or dry yet. Both have been recommended for different reasons and there is a lot of speculation and opinions on which one is better. I need to do a little more research so I can decide exactly which kit I want to use on my application.
I looked at the dvd. Guess after I get the parts together Ill have to add the dvd to the budget. I would really love to be able to decently tune a car, especially my own.
No, you didn't read my post properly. I specifically said:
"On all motor, the LS3/LS7 42# injector is good to approx. 550 rwhp at 90% DC (duty cycle)."
Those are factory GM injectors. They are rated approx. 42# at 58 psi.
As for the Ford 42s, they flow approx. 42# at 39.15 psi. Your system runs at 58 psi, which makes them flow 52.x #. They are good to approx. 675 rwhp N/A (naturally aspirated). On a blown GM setup they are only good to approx. 575 (you have to account for the power loss that is required to turn the blower).
Also, you didn't answer if your going to run a wet or a dry shot. If you're running a wet shot, which is highly recommended, injector size does NOT matter. The injectors only come into play if you're running a dry system.
Formerly known as RWTD
Toys: '22 Tesla Model S Plaid / '20 Chevy Duramax / ?20 Sea-Doo RXT-X (2)
Ok I understand now. Im not sure if Im running a wet or dry yet. Ive read a lot of different opinions on both and need to do a little research for myself to see which one will be right for my application and my preference.
I am in 100% agreement with RWTD, I would seriously consider the wet shot if I were you.
2017 Silverado LTZ
What are some of your opinions on wet vs. dry? Why do you consider the wet kit better?
There is program that you can adjust any injector size its done by EC_tune in the sticky but i don't recommended . because you are going to rap your tune as RWTD says it better you get the DVD it will tell you every thing you need for the injectors and it will learn you how to tune .
I got the DVD but it doesnt really help because all the injector data that is included comes off the excel sheet and doesnt really explain how to scale injectors from nothing.
What ever happened with this? why does finding info about scaling injectors seem to be so difficult? Buy a $259 cd is the answer I see most often
I looked in the help menu and see where to change the info and it says it will do it for you.. I think... LOL but I'm not sure where to enter the info still or am wrong?
Open up the Unit Conversion window found under the Tools menu.
In the lower right, enter in your new injector flow rating and the fuel pressure it is rated at.
Then enter in the fuel pressure of your fuel rail.
Your new injector flow rate will be calculated automatically. This rating is for 0 VAC.
As manifold vacuum increases the injector flow rate will slightly increase
So..... I look there and the boxes are current fuel pressure and current INJ flow and new fuel pressure and new INJ flow...
I don't know what was in there for injectors, can't remember but I do what I have now and what my pressure will be as soon as I get a reading....
So. if I have 62 lbs on the rail and the infamous 60 lb what ever its called now Siemens then what do I do next?
I figured the avg of the flow rate of the Siemens at 43.5 and 87 psi which is what they list info for and come up with 72.54 for my application at 62 psi.
then what do I do? Enter the 62 and 72.54 in the new FP and new INJ box?
If so then what? it Doesn't really say what to do in the help after that?
Ok I found redhardsuprahs excel sheet..but the question is still how to use that conversion calculator?
The spreadsheet will work just fine if you have Greg's DVD and you're not running GM spec'd 58 PSI or 4-Bar (or OEM vacuum referenced on '03 and earlier trucks) fuel pressure. BUT it's ONLY good for rescaling the injectors for different pressures to give you a proper Injector Flow Rate based on known GOOD values.
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update.... bought a fuel pressure tester to use to get an accurate pressure reading off the rail
started another thread and got some answers to the questions about HP as well so between that thread and the GB dvd I'm on the right path now.
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