injector duty cycles

[AliveAgain]

I have an 2006 flhtcui and am wondering how far with the mods I can go before I would have to change out the injectors to a larger size? I have nothing plan as of yet but just wish to cover the basics of what I'll need should I go bigger.

[INDEPENDENT 1]

I don't think anyone can answer your question until you decide what you're going to do for modifications. Depending on the tuning device you're using, you can see duty cycle of the injectors or pulse width and calculate the duty cycle using pulse width.

[strokerjlk]

4.3 is rated at 55 hp two =110 hp
5.3 135 hp
They will go a little more than that , but your pushing duty cycle.

[Burch753]

according to Zippers, 5.3 will handle a 124" B2 headed 70mm TB to every potential it can throw... and that my 6.2's are way to big. lol.

[AliveAgain]

So I should be fine going to a 95" and head and cams set up. Albeit the upper limit. I don't like to go passed 90%. Burch 753, do you have any atomization issues with the too big injectors?

[strokerjlk]

Originally Posted by AliveAgain

So I should be fine going to a 95" and head and cams set up. Albeit the upper limit. I don't like to go passed 90%. Burch 753, do you have any atomization issues with the too big injectors?

You need to check and see if you have 8 deg or 25 deg injectors in there now. The stock 8 deg could have been replaced with 25 deg if the owner did the service up date.
Either way you could have 3.89 in there now. I would go to 4.3 while it is apart. If it wasent done ready

look on the injector The 8's are pn 27625-06 and the 25's are pn 27709-06A.

[AliveAgain]

Thank you for the replies. I believe I have the up dated injectors but will double check them later. Can some one inform me, should I go bigger, who has the better product for the money. I know a lot of people like to stay with the MOCO, but I have found aftermarket, when you know where to look, can or may have better and cheaper products. What about raising fuel pressure? Marren Fuel Injection http://injector.com/ is in the next town over.

[01fxdx]

I found some of the se injectors cheap used. The 4.3. I had the old injectors and felt it was good insurance. As far as pressure, too much will likely have an adverse effect on spray pattern, perhaps blowing fuel past the needle as well.

[strokerjlk]

Originally Posted by AliveAgain

Thank you for the replies. I believe I have the up dated injectors but will double check them later. Can some one inform me, should I go bigger, who has the better product for the money. I know a lot of people like to stay with the MOCO, but I have found aftermarket, when you know where to look, can or may have better and cheaper products. What about raising fuel pressure? Marren Fuel Injection http://injector.com/ is in the next town over.

Marren is ok.
SE is ok .
HPI is ok
You have lots of choices for your 06 model.
Just stay away from v rod injectors.