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scarceller scarceller is offline
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Join Date: Oct 2006
Location: Southern MA
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I do not know of any 4 or 6 hole injectors that are lo-imp. All modern 4 and 6 hole injectors are now disk style injectors and they no longer require lo-imp. Basically lo-imp was used in the early single spray injectors to achieve very fast on times, these lo-imp injectors typically have on times in 0.5ms range.

But the more modern injectors are now hi-imp and can have on times in the 0.6 to 0.8 ms range without needing to be lo-imp. The technology between the older single hole and the newer 4 and 6 hole is very different. The newer injectors can really help clean up idle as well as slightly better MPG simply because they atomize fuel better at low flow rates. The older injectors did not atomize fuel very well and they sprayed at the back side of the closed intake valve to utilize the hot valve surface to help atomize the fuel but at low flow rates this practice is not perfect. However, at hi flow rates (Heavy load like Wide Open Throttle) either injector functions well.

Originally Posted by 911 tweaks View Post
possible dumb question... do you know of any "drop-in" 4 or 6 hole injectors that are LOW impediance so the chip does not need reprograming...? thx, bob
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Old 09-30-2015, 06:56 AM
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