I had my car tuned to approx 97% injector capacity with my TN kit installed. I am making 385 RWHP. I am not intertested in making more power. Will my car be safer by just swapping the 480 injectors since they will be operating at much less % capacity? I will tune the car for the same power. Will this be a safer situation than running with the TN 380 injectors at 97% duty cycle? Or is switching the injectors accomplishing nothing......

Respect
JET

 

it will be safer to get the duty cycle down. factors such as temp or altitude changes from when you had it tuned can change and run those injectors past 100% possibly. the injectors are pretty cheap and easy to do, so safe insurance.

 

440's will get you to around 84% duty cycle. Anything over 80% is considered not good on a daily driver because the injectors tend to start to fail over time. I would go with 550's and get it retuned because then you would be around 67% duty cycle. Just my opinion.

 

getting too big of a injectors is not good either.. getting it right around 80% at peak will yield the best results.

 

I was told by going with the 440 's around 400-425rwhp you will get a much cleaner tune. I am getting my kit installed next week and hope to be in that hp range, should I have went with the 550?

 

I was in that same predicament...440's or 550's...I went with the 440's which should be good for 400+ rwhp (goal) with a good tune and DC.

Jet your going to go get tuned all over again?

 

As a general estimated rule of thumb, the injector size is the HP you can make on a 6 cylinder motor. Ex 380cc=380hp ,440cc=440hp,550cc=550hp



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Yes. I guess I am going to invest in a set of 440's and a new tune.

MRC.... are those HP #'s @ 80% or 100% duty cycle. I imagine those HP #'s are for 100% duty cycle. My 380 injectors gave me 380 rwhp at close to 100% duty cycle.

Thanks for the responses.

Respect
JET

 

80% duty cycle is the industry standard for rating injectors..

 

You will be fine... will actually be safer!!

 

what will my 650cc injectors run at with 500 whp?

Greddy TT / built block / 9:1 compression? should they be safe?

 

I am using 650cc, AAM fuel system at about 53 static psi and at 530 whp were seeing 80% duty cycles with an 11.5 A/F..530 whp is close to the 650hp at the crank.