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Jak's a great guy. The SD box just controls how the turbo operates. The chip is controlling the whole fueling system, interacting with your AMM to fine tune your mixture and keep you from going too rich or too lean. As your turbo spools up it is adding air, so your mixture gets too lean. That can cause a knock, which is a premature detonation in the cylinder that is very bad for your engine.
with the large injectors and FPR and the standard chip, you have a bit of the worst of both worlds. You're outside of the range of your ECU ability to properly mix the fuel. So you're rich at idle and when not boosting, and lean when boosting.
SD also makes a fueling chip that is likely cheaper, but the consensus (at least on this board) is that Jak's chip is the best out there. Landjet has some experience trying out different chips, and he loaned me several different makers to test (many years ago). Jak's gave me the best idle, gas mileage, and smooth power.
If you ever want to change your AMM (which I recommend if you're seriously devoted to the car), Injection Labs in Boulder CO will do wonders. That's really the other half of the equation. The ECU (and its chip) tell the injectors what to mix, but the AMM and the oxygen sensor tell it what the ingredients are (how much air is going in and how much fuel is being used effectively.
The other typical limiting factor on optimizing the performance of these engines is the intercooler. The stock intercooler is tiny and not very effective. The Side-mounted mitsubishi intercooler that Jak has on his website is very easy to install and a major improvement over stock. I made one myself (cost about $150, 75 for the junkyard IC and 75 for the welding to modify it). Eventually I replaced it with a front mounted IC.
the beauty of these cars is that you can modify them bit by bit as your budget allows.
Posts in this Thread:
- First Swedish Dynamics box, now 3 bar & red tops, now CEL?, Bobwithasaab, Mon, 17 Oct 2016 17:19:50
- Re: First Swedish Dynamics box, now 3 bar & red tops, now CEL?, SWEDISHDYNAMICS , Fri, 10 Feb 2017 11:44:291
- The APC box and 3 bar FPR are irrelevent, Notnoel , Mon, 24 Oct 2016 12:59:25
- Re: First Swedish Dynamics box, now 3 bar & red tops, now CEL?, lms, Thu, 20 Oct 2016 08:54:40
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