I was wondering what size injectors would be a happy medium for size to keep fuel economy when Im not ballz to wall and yet got the power when I want it, I was told 40overs would be perfect any ideas ??
Injector size!
- Thread starter totalanarchy
- Start date
Many say stock injectors provide the best mileage. The question is power level your shooting for.
if your running a stock pump your stock injectors can get you pretty close if not all the way to maxing out the potential of your stock cp3 now that being said larger injectors can yield safer tuning I have 60s and I got 23mpg on a trip from nc to pa
My LMM pump is keeping up with my 50% over quite well. My new Lb7 did alright until my hot tune. Many guys are running a stock cp3 with bigger sticks. I am a firm believer there is no need for dual fuelers on a stock bottom end.
I am holding 22000 psi at 2250pw and what pulse with is your big tune now im not saying that a stock pump can not hold bigger injectors but the pulse with is going to be short resulting in safer tuning example if your stock injectors could hold 3400us a 50 precent injector should be able to hold a 2550us pw do you see what im saying
Pulsewidth has a lot to do with it but there are other factors that play a role also. I see what you are saying and no I am not even up to 3000 cause of my turbo and stock bottom end. With 40% overs he is border line.
What motor ?
I would probably agree with 40s.I wouldn't waste my time with 30s and if you haven't built the motor forget about 60s or higher.JMO
I would probably agree with 40s.I wouldn't waste my time with 30s and if you haven't built the motor forget about 60s or higher.JMO
it was just an example and yes there are many factors in holding rail and in the the case of this gentleman were trying to help it would help to kno what mods he has what his goal is does he have a built trans what model truck he has would all help us help him filling out your sig helps us
why would u stay away from 60s or higher its not uncommon to put 100%s in a stock turbo and cp3 truck it would just help in keeping pulse with down im not trying to call u out i have always respected your opinion and advice you have given me and other people just curious
I just have seen people on here run 50s or higher on a stock lower end (that's why I asked what motor if the lower is stock) with a 366 make 578 horse running out of fuel with 50 overs,now if you had a smller bodied injector like lly lbz lmm I might be tempted to go larger only because I believe the smaller injectors need to be larger for quicker delivery.Theres a reason lb7s with a 90 100 horse tune can run without a lift pump and live.I could put the same tuner on an lly lbz and run the horse power tune and the truck just couldn't run it it would limp.For that reason I love my big fat lb7 injectors.I run 60 overs in my truck at 11.64 and I was told if I want to get serious go to 80s.This is my opinion I have no bullet proff facts to prove it just what ive seen and how I feel.
Yup I still wouldn't waste my time with 30s in either motor and yes to equal 60 overs in my truck you would want to got 100s.Also an lbz lower will handle more horse before things break.Theres a lot of factors to consider really.If a guy is going to dd 90% and hit the track 6 times a year on tune 5 well may be he wants to stay stock and really push the stockers hard at the track............just stay away from tune 5 on the street or things are gonna get hot.
Yes.I believe the op was on a stock pump so I was trying to use comparitives. The truck was also an lb7 with the 366 and 50 overs.
What were you running for fuel? over size pump? stoker? and what size injectors?
i donr know whats in It but their bad so I got dual fuelers mahle pistons carillo rods built lower ompound turbo kit (add turbo) and he never put in a lift pump so any advice I was thinking 200 air dog and I wanna keep my fuel economy then have the ponies at the track so im thinking 40% overs or 60 overs I wana be safe with injectors for my hot tune
A stock pump absolutely will not keep rail up with 50's at 2550us. No chance in hell.
Have you actually logged rail pressure for an entire 1/4 mile run? I have a hard time believing you can maintain 22,000 psi on a 2250us tune with 60% injectors and a stock pump. What is your desired rail pressure on that tune also?
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Everyone has derailed from your question so to answer you either a airdog 165 or 200 will be good. I'm currently running a 165gph with 80 oner injectors. I wouldn't go 40's id go bigger like 60 or more. That way you can always have a little more than a little less.