OX66 vs HPDI, Whats the difference?

[homey]

Hello,<br /> Whats the difference between these fuel injection systems? I understand the HPDI is high pressure injection which probably means a better more distributed burn in the cylinder...But, does it equal better gas mileage? Which is more reliable? It seems the better deal $$$ maybe with the OX66? Whats your opinion on these EFI's ? Thanks.

 

[bigbrownbuku]

Re: OX66 vs HPDI, Whats the difference?

hpdi is direct injection, directly into the cylinder. ox66 is intake injected, before the crackshaft via intake ports to the cylinder.<br />with correct maintenance both will give you many hours of reliable performance.

 

[WillyBWright]

Re: OX66 vs HPDI, Whats the difference?

DFI (HPDI) engines are different than EFI (OX66) engines in that they shoot the gas directly into the cylinder at the appropriate time which makes them much more efficient. EFI motors lose some of the fuel directly to exhaust without burning first. At higher RPMs 2-strokes are quite efficient no matter if they're EFI DFI or Carbureted. It's in the low to midrange where DFIs can save you a lot of gas as opposed to EFIs and Carbureteds. Tests show that DFIs are generally more fuel efficient than 4-strokes as well as superior in performance (the specs are close).<br /><br />As far as repairing, carbureteds are readily repairable by anyone knowlegable. EFIs need a bit more expertise and sophisticated equipment, DFIs more than EFIs. Reliability is about even accross the board when it comes to Yamahas (excellent). Maintenance varies depending on the induction type, but they all need maintenance. Non-carbureteds seem to need a bit less TLC suprisingly.<br /><br />Many very popular lakes already restrict the use of boat motors to 4-strokes and DFI 2-strokes. More will follow. The wave of the future is definately aganst carbs and EFI in 2-strokes.

 

[swist]

Re: OX66 vs HPDI, Whats the difference?

If you use the topics in this forum as an admittedly unscientific survey, it would appear that ox66 systems seem to be more prone to problems than carbs, but that could also be because they are more sensitive to proper maintenance. There is relatively little talk in here on HPDI problems but that is probably because they are new and the engines are still under dealer warranty so there's not much DIY fixing going on.