I want to run two side by side fuel and ECU systems when I add boost to my project car, a 2000 A8 40v engine.
Off boost ---> Gasoline ---> stock Fuel tank/pump --> stock injectors ---> stock ECU
On Boost --> E85 or E-100 --> Spare-Tire shaped fuel tank/Ethanol safe pump --> AEM F/IC-8 and 8 larger injectors
This guy has been doing it for a long while using Race Gas in tank 2 at low boost with only the stock ECU, 2 tanks, 2 pumps and 2 sets of injectors. Sequential Dual Fuel Turbo Malibu
Turbo Malibu's boost is modest since he's running it all off of the stock ECU. I'd like to take it one step further and use a piggy back controller for the second set of injectors. Both systems would run simultaneously, I'd use a Hobbs switch to sense boost and switch the hot feed from the stock to the secondary injectors. Both systems would think they are in control, but only one system would ever have power to the injectors. The piggy back would take charge of fuel and timing on boost while telling the OEM ECU that there's nothing to see here, remain calm and move along.
The idea would be to run stock injectors and crappy CA gasoline off boost, then toggle the injector hot feed to the second set of injectors using a hobbs switch. Seems a little primitive though. I'm wondering if there is a way to stage sensors or switching relays to have some overlap during the hand-off, so the gasoline injectors keep feeding for two or three revolutions while the ethanol injectors start firing. Is there an easier way to do this? Anyone BTDT?
I've got a supercharger on the shelf and will fab up all the bits. A swappable crank pulley is done, but I want to think it all through before I attack it.
Thanks,
Brian C.
"Oh bother," said Pooh as he chambered another round.
