carl0s Posted November 16, 2005 Share Posted November 16, 2005 Now that the air is cold, I'm easily hitting my high-boost alarm (which would shortly be followed by fuel-cut) in second gear now, so it's probably time to fit the Thor FCD that's been sat here for a couple of months. What I want to know is, will the car (UK spec) fuel all the way up to 1.2 bar or will it stop fuelling at the boost level it sees (where the FCD clamps it to). Does boost have anything at all to do with fuelling or is this taken care of by airflow meters? Quote Link to comment Share on other sites More sharing options...
SUPRALOOPY Posted November 16, 2005 Share Posted November 16, 2005 i'd like to know this too:D Quote Link to comment Share on other sites More sharing options...
Ian C Posted November 16, 2005 Share Posted November 16, 2005 If you want to stop fuel cut on a UK spec, take the hose off the MAP sensor and stop it up with a screw. That's it. Of course, that means any overboosting won't be registered, unlike with the Thor unit where it moves the fuel cut rather than removes it. The UK spec car uses the MAF for all it's fuelling, the MAP is there for one purpose only - to watch for overboost. On a j-spec it's used for fuelling too, so it's vital. In this case the FCD clips the signal at around 0.99bar of boost as it's only at 1bar+ it initiates fuel cut (it's not a simple switch, cut comes in based on time and level of boost over 1bar but anyway). Fear not about the fuelling because by the time the stock ECU sees 0.9+bar of boost it holds the injectors open 100% anyway. Which on 440's with a decent fuel pump will run 1.2bar of boost on stockers. Seeing as you fuel the same for 1, 1.1, and 1.2bar of boost (100% duty cycle) you may as well run 1.2bar -Ian Quote Link to comment Share on other sites More sharing options...
carl0s Posted November 16, 2005 Author Share Posted November 16, 2005 If you want to stop fuel cut on a UK spec, take the hose off the MAP sensor and stop it up with a screw. That's it. Of course, that means any overboosting won't be registered, unlike with the Thor unit where it moves the fuel cut rather than removes it. The UK spec car uses the MAF for all it's fuelling, the MAP is there for one purpose only - to watch for overboost. On a j-spec it's used for fuelling too, so it's vital. In this case the FCD clips the signal at around 0.99bar of boost as it's only at 1bar+ it initiates fuel cut (it's not a simple switch, cut comes in based on time and level of boost over 1bar but anyway). Fear not about the fuelling because by the time the stock ECU sees 0.9+bar of boost it holds the injectors open 100% anyway. Which on 440's with a decent fuel pump will run 1.2bar of boost on stockers. Seeing as you fuel the same for 1, 1.1, and 1.2bar of boost (100% duty cycle) you may as well run 1.2bar -Ian Very very interesting. Thank you so much Ian So a J-spec would be running rather rich at 1-bar, and probably about right by 1.2bar (AFR wise anyway). How bizzare. I suppose it's like a desperate safety measure. Regarding my UK spec, that seems like the preferred solution for me then, since I have a red-light boost alarm on my SPA gauge, and boost-cut is provided by my right foot. Do people actually *do* this though - block the MAP hose? No cons to it? Quote Link to comment Share on other sites More sharing options...
ronttuk Posted August 11, 2013 Share Posted August 11, 2013 Is this information correct ? Do I need to fit the Thor fcd I bought or not lol Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.