95 Geo Tracker with Audi turbo, no intercooler. We have an Air/Fuel gauge. We are wondering if anyone else has a similar set up that could give us a head start on how to increase fuel under boost. Thanks.
You need around 30 pph injectors, you also need to ohm out the stock injectors to see if they are high or low Z units, stock ecm does an OK job with a turbo, but 4 or 5 psi, ya, that will change because boost is addictive 😉. Definitely take the time to do something for an intercooler, you need it, either an air to air or water to air, which is more compact, the more cool the air the better, you can't get best power without one. And premium gas won't be enough to stop knocking, you will destroy your new engine otherwise. I added 4x19 pph ford escort injectors to the 8v manifold, or were they 15 pph, I forget now, but they were the light brown ones. Those along with the TBI injector which is 50 pph gave me enough fuel for 10 psi boost but a little bit lean, they were maxed out in pulse width, I fired those separately from a Megasquirt 1 unit, I now have the daughter card for an upgrade to more tables and spark control / boost retard. I got some turbo Thunderbird injectors, but they totally drowned the engine and I didn't ever fix my tune before I stopped driving my kick, now it's been sitting a long time taken apart for repairs and upgrades in the driveline and I never finished her.