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ronglove
11-13-2008, 09:48
It's time to replace my stock injectors; both stock and marine types have been recommended. What should I expect if replacing stock with marine injectors

6.5 Detroit Diesel
11-13-2008, 11:21
Correct me if I am wrong anyone, but seems to me that this has been much talked about. The way it was explained to me was that marine injectors are set to a higher "pop" pressure than stock, but the only way to take advantage of the higher "pop" is to turn/chip the IP up.

DmaxMaverick
11-13-2008, 11:36
True "marine" injectors will have a higher pop pressure, and higher flow nozzles. The two features must go together, for it to be a "marine" grade injector. Most "marine" injectors advertised are not "marine" injectors. Most are either stock injectors shimmed to pop higher, or stock injectors with marine nozzles. A true marine injector does not "require" any pump modification, unless greater maximum fuel delivery is desired (more maximum power). The injectors determine the output pressure of the IP. The IP only controls the timing and fuel volume. Ideally, greater efficiency can be had with only a higher pop pressure. Higher pressure creates a higher rate of fuel atomization. If you couple the higher pressure with a higher flow nozzle, the atomization is not optimized. More fuel will be required to take full advantage of it. Add to that accelerated pump wear due to the higher pressure demand, and your ROI may disappear, even with increased economy.

For this reason, I recommend only stock level injectors. If you want to "optimize" efficiency, opt for the "high pop" stock injectors, with the understanding that it may decrease pump life.

More Power
11-13-2008, 12:11
It's time to replace my stock injectors; both stock and marine types have been recommended. What should I expect if replacing stock with marine injectors


If you have a marine pump, sure get marine injectors.... If you have a stock on-road pump, a set of matching injectors would provide for more predictable results.

On another note, has anyone produced a careful engine dyno or BMSFC fuel consumption comparison between factory new stock injectors and new marine injectors?

Jim

suburbanK-2500HD
11-13-2008, 21:16
feel like sharing some experience with marine injectors.
i have had them since mid summer 08.

installed them before going on vacation. towing my caravan at 2,2ton.
It was a noticeable change.
i had more power towing, specially uphill i notice the change.
My friend with a 97 6,5, and less towing weight disappeared behind me..
fuel economy wasnt too bad, cruising in 80 -90km\h i used about 1,8ltr pr mile.(10km). temperature was monitored with the GMTD scan tech, and didnt reach any critical levels...