Injector size and brand
That cam with a carb, 243 heads, and good supporting parts could get up to 500HP at the crank. Less with LS6 intake and even less with an LS1 intake. So you will have to come up with your current power expectations and what you will add later.
You need about 50lb/hr for each 100HP, but you want to run the injectors with about a max of 80% duty cycle so use 62.5 as a fast number. It also takes about 32lb/hr per 100HP when running dry nitrous.
500/100=5
5*62.5=312.5lb/hr total
312.5/8=39lb/hr injectors or
39*10.5=409.5cc injectors
Since most are rated at 3 bar or 43 psi and LS runs at 4 bars or 58psi you can use smaller injectors. 353cc rated @ 43 will flow 410cc at 58psi. So,
353/10.5=33.6lb/hr should work for you at 500HP NA
You need about 50lb/hr for each 100HP, but you want to run the injectors with about a max of 80% duty cycle so use 62.5 as a fast number. It also takes about 32lb/hr per 100HP when running dry nitrous.
500/100=5
5*62.5=312.5lb/hr total
312.5/8=39lb/hr injectors or
39*10.5=409.5cc injectors
Since most are rated at 3 bar or 43 psi and LS runs at 4 bars or 58psi you can use smaller injectors. 353cc rated @ 43 will flow 410cc at 58psi. So,
353/10.5=33.6lb/hr should work for you at 500HP NA
hi i also have 1998 5.7 all stock looking to up grade. looking like th. body ,injectors ,fuel rail ,intake ,maybe cam. does the efi run better with return line. i see u r knowledgeable on this my first ls engine.been looking all over internet for some help.been looking at the intakes get trail blazer or 6,0 is that worth it. thanks
I just got a FAST 92mm intake and TBon eBay for 1100 shipped, normally a 1500$ deal before shipping and it’s brand new in box, that’s the same price as a LS6 intake and TB, could pass up, there r still 3 available! I recommend it.






