E-Force with Cam Fuel Injector Question
Thread Starter
Safety Car
Joined: May 2016
Posts: 4,669
Likes: 1,849
From: Erlanger, Kentucky
E-Force with Cam Fuel Injector Question
Hello.
I have the 599 E-force kit on my 6-speed manual 2011 Grand Sport. I had it dyno tuned about a month ago and the car is running good.
But I am thinking of adding an LS9 cam. I know there are several options of cams that will make more power but the bang for the buck of the LS9 plus being able to keep my existing valve springs is very attractive to me.
To the point however, when I had the car dynoed, my tuner said that my injectors were at about 87% duty cycle. If I am not mistaken, it is recommended to not go much above 85% (tuner said I was fine). Should I go with an LS9 cam, would it push the duty cycle even higher? Would I need bigger injectors?
Since the LS9 cam is specifically optimized for PD blowers would the injector duty cycle stay the same or possibly go down since it would be better matched to the engine?
I have the 599 E-force kit on my 6-speed manual 2011 Grand Sport. I had it dyno tuned about a month ago and the car is running good.
But I am thinking of adding an LS9 cam. I know there are several options of cams that will make more power but the bang for the buck of the LS9 plus being able to keep my existing valve springs is very attractive to me.
To the point however, when I had the car dynoed, my tuner said that my injectors were at about 87% duty cycle. If I am not mistaken, it is recommended to not go much above 85% (tuner said I was fine). Should I go with an LS9 cam, would it push the duty cycle even higher? Would I need bigger injectors?
Since the LS9 cam is specifically optimized for PD blowers would the injector duty cycle stay the same or possibly go down since it would be better matched to the engine?
Race Director
Joined: Mar 2011
Posts: 13,262
Likes: 3,151
From: SW Florida
2021 C6 of the Year Finalist - Modified
Your now at 87% duty cycle ... The LS9 cam certainly will increase your RWHP ... How much? ... I don't think anyone here can can give you an accurate number.
LS3 Cam:
Dur: 204°/ 211°
Lift: .551” / .525”
LSA: 117°
ICL: 120°
Overlap: -26°
_______________________________
LS9 Cam:
Dur: 211°/ 230°
Lift: .558” / .552”
LSA: 122°
ICL: 122°
Overlap: -23°
LS3 Cam:
Dur: 204°/ 211°
Lift: .551” / .525”
LSA: 117°
ICL: 120°
Overlap: -26°
_______________________________
LS9 Cam:
Dur: 211°/ 230°
Lift: .558” / .552”
LSA: 122°
ICL: 122°
Overlap: -23°
Le Mans Master
Joined: Dec 2005
Posts: 6,999
Likes: 1,685
From: Southeast TX
If you're going to all of the trouble and expense of a cam swap, why not use a cam that fits your goals? If your goals are a miniscule increase in power along with great manners, use the LS9 cam (but why?). Congrats, you just saved a few hundred bucks, you have a minimal power increase, use your stock LS3 valve springs, you're also putting your valve train and your engine at risk. Lots of really good cam and valve train options out there that will give you more power, good reliability, and good driving manners. An LS9 cam is good for a trot line weight and not much else. Probably why it's so cheap. You'd be better off taking that $140 along with the labor cost, to Vegas and bet on the Houston Texans to win the super bowl.
And yeah, if you increase power much at all, you're going to need more injector.
And yeah, if you increase power much at all, you're going to need more injector.
Race Director
Joined: Mar 2011
Posts: 13,262
Likes: 3,151
From: SW Florida
2021 C6 of the Year Finalist - Modified
