about what power/mod level do we start needing more injector? i know a bunch of FBODY guys upgrade them with heads/cam setups and tuning, should we basically follow the same path and upgrade with headers/cam and all the mods that we're seeing more of in trucks? bigtex, you're the injector king, what's your opinion on this??

 

excluding the 99 year model and the flex-fuel vehicles, all the trucks and SUVs have the same basic injector. I think it should support between 320 and 350 rwhp N/A (at stock fuel pressure). Since not many guys are nearing this mark on their trucks, its not too big of a concern. But if you tru to run a dry nitrous shot, you'll be in trouble. If you go with a bigger motor or a good heads cam package, you'll need injectors. The best way to determine you need injedtors is to log the injector pulse width with autotap or similar. You can do a calculation based on the rpm to see if you are needing more injector. I think the value for 100% on time at 6000 rpms is 18ms and 20 ms at 5000 rpms. Just log rpms and pulse width, so you can get a more accurate relation between the values. If your values are larger than those at those rpms, you are going past the physical limits of the injectors, and need to replace them. Typically, if you spin it to 6000 rpms+ and are making some good power, you'll be stretching the stock injectors. If you keep the rpms down, you'll have more time between engine cycles for the injector to spray, letting you get by with smaller injectors.

I don't think this was a very good explanation, sorry.

 

makes sense actually....basically more power=more injector, so since i'll spray a wet shot i should be ok, until i go with the 370 with the heads and bigger cam early next year. but i should be ok for now.