I am rebuilding my 500 engine and one of the things I will be doing is installing an MT #5 cam from MTS. This is one step above the base or factory spec cam. My question is will I need to reprogram my ecu for this cam?
Another thing I heard of some guys doing was wire in a variable
resistor in place of the temp sensor so by telling it was still cool it would richen it up by the dial
of the resistor..
A 76 EFI system has a rather simple minded curve, completely open loop, and with no ignition
control at all. But it is not true, that it can't be retuned. Varying one resistor can shift the
amount of fuel (injector pulse width) to match a different displacement, or breathing. I have
already done this multiple times making 350 ECUs run 403s. Easy to do while driving.
Changing the temp sensor resistance is a very poor approach to the issue. This was well
demonstrated when comparing the methods on the Maidment Haverhill car project. This
adapted a 350 EFI to a highly modified 403. I don't have the details on my PHOTOBUCKET
just yet. Bruce Roe
Why do a rebuild and use a different cam? It will require a lot of other fine tuning which makes the project unnecessarily complex, without getting noticable gain. Unless you want a lot of gain for racing I would stick to the original setup to have like-new state of engine which will give you plenty of performance to cruise.
Well according to the guys at MTS the cam I would like to use wont require anything like that. I can use the factory valve train etc. It's one step up from the basic factory type cam. I know I am taking what they say on faith since I am not a mechanic but MTS seems to know their stuff.