4 ms·
If described correctly, it is a different concept. Variable cam timing in the context of VANOS / Vtec / VVT refers to variable timing on the camshaft that contr
by unregistereddev 5y ago
If described correctly, it is a different concept. Variable cam timing in the context of VANOS / Vtec / VVT refers to variable timing on the camshaft that controls valves.
This sounds different, and I think it refers to mechanical fuel injection. Several automakers experimented with mechanical fuel injection in the 80's and early 90's, but I think the concept died pretty quickly. It was rather complex, failure prone, and less efficient than EFI.
- linksnapzz 5y agoMuch earlier than that; there were running mechanical fuel injection protoypes for gas engines before WW1 (diesel got FI quicker); mass-market mechanical fuel injection followed WWII-the Mercedes 300SL had FI in 1955. Thing is, mechanical FI is almost as hard to tune for emissions and economy as carburetors, so electronic control is necessary. Chrysler offered an EFI system based on the Bendix Electrojector in '58, but the tech was not fully baked, for one thing, the electronic controls were vacuum tubes in an enclosure in the dash; I think there may be one remaining operational '58 Imperial with that system still running.... Anyway, Bendix sold the patents for the Electrojector to Bosch, which a decade later had developed them into the J- and K- Jetronic transistorized throttle-body EFI systems so beloved by Porsche 914 enthusiasts.
- dclowd9901 5y agoOh interesting. The way I read it it sounded like it was manipulating the cams. I have heard of mechanical fuel injection — pretty cool stuff but yeah very finicky.