I am building a 383 and I need to know what injectors I should use. I don't want to get some that are way too big; however, I don't wanna go to small either. I going to be running a fairly large solid roller cam, lt's...ported everything. So yeah, gimme some advice. Jason

Also, would I have to upgrade my fuel pump ??

 

It definitely wouldn't hurt to upgrade your fuel pump. Racetronix has a nice kit that I got, haven't installed it yet though...search Racetronix for more info on their kit.

I also got my injectors from them. I opted for the 42# injectors, but I think they may be a bit overkill.

It comes down to what injector duty cycle you want to run (Which "they" state at 80% is about right) and what your BSFC (brake specific fuel consumption) is. It will most likely be somewhere between .40 - .50, .40 being extremely efficient and .50 being more of a pig.

This chart should help you out. There's 3 tabs at the bottom.

http://paradox.shacknet.nu/dave88lx/.../injectors.htm

 

42# is what it will take to make decent HP out of a 383.You could go to 36# but you will have to buy a godzilla pump to make HP.You need the Walbro 340 pump anyway to feed the 42# at stock fuel pressure.You can make 530FWHP with 36#@49PSI fuel pressure,with a 85.5% duty cycle.A good 383 should make 600++FWHP,depending on heads,intake,and cam.

 

Well...if my car hits 500rwhp I will definately wet myself....we will have to see....how much do those walbro 340 pumps run anyways?

 

About $100.00.How big are your heads?
That's 530 flywheel HP.

 

I haven't bought the heads yet....but I am getting state 2 from c-motorsports.com. I hear they do really good work and that the heads flow really well so hopefully I will have it runnin nicely in a few months.

 

280CFM is capable of making you 575 at the flywheel,if everything else is correct.Thats 517 to the tire with a stick. Now the 36# won't work.

 

Well i was shootin at least 450.....but 500 was secretly my goal....I am trying not to get my hopes up too high and then get let down big time on the dyno....but if she gets that fast I am all about it!