When is a motor just a motor, just a motor?
When is a motor just a motor, just a motor?
(OP)
Dear Gentlemen,
I have another head scratcher that's really been squeezing my melon ever more and more. Here's what I don't get...
Let us take, for example, two engines like the Ford 4.6 sohc and the Ford 4.6 dohc. Both motors are fuel injected, metered by mass air amd O2 sensors, have identical stroke and identical bore yet a sohc computer will not run a dohc engine and visa versa. Moreover, as long as you have the same number if pistons, it doesn't make sense (to me) why all computers aren't interchangeable because the built in feedback systems should compensate for any values unexpected by the computer. I do understand that this isn't so. You can't even get a 4.6 dohc to start with a sohc computer... but I fail to understand exactly why. I once read an article about some Ford engineers building a proto-type V12 and they used two computers from two in-line 6's to run it, so maybe a motor IS just a motor. What kind of gamble would I take attempting to wire GM's 4.6 dohc Northstar to Ford's 4.6 dohc wiring loom and computer? Please explain why that's just a boob-shooby idea.
Happy Holidays,Walter Carter
Palm Springs, California
I have another head scratcher that's really been squeezing my melon ever more and more. Here's what I don't get...
Let us take, for example, two engines like the Ford 4.6 sohc and the Ford 4.6 dohc. Both motors are fuel injected, metered by mass air amd O2 sensors, have identical stroke and identical bore yet a sohc computer will not run a dohc engine and visa versa. Moreover, as long as you have the same number if pistons, it doesn't make sense (to me) why all computers aren't interchangeable because the built in feedback systems should compensate for any values unexpected by the computer. I do understand that this isn't so. You can't even get a 4.6 dohc to start with a sohc computer... but I fail to understand exactly why. I once read an article about some Ford engineers building a proto-type V12 and they used two computers from two in-line 6's to run it, so maybe a motor IS just a motor. What kind of gamble would I take attempting to wire GM's 4.6 dohc Northstar to Ford's 4.6 dohc wiring loom and computer? Please explain why that's just a boob-shooby idea.
Happy Holidays,Walter Carter
Palm Springs, California





RE: When is a motor just a motor, just a motor?
If there is no standard for the number of pin-outs on the ECU and what there assignments are, and the number of teeth on the crankshaft position sensor wheel, and the nature of the reference zero-position on that sensor wheel, and what the waveform of that sensor is, and how the cam position sensor signal and waveform is, and on and on and ON, there cannot be interchangeability because every designer will make their own choices.
And, don't forget the possibility that the parts are *deliberately* not interchangeable, for a wide multitude of possible rationales, rightly or wrongly.
RE: When is a motor just a motor, just a motor?
RE: When is a motor just a motor, just a motor?
If crank position sensors are out of phase, depending on how they are set up, it is not that much of a stretch to rephase them.
Regards
Pat
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RE: When is a motor just a motor, just a motor?
Is there anything that makes you think otherwise?
Cheers
Greg Locock
SIG:Please see FAQ731-376: Eng-Tips.com Forum Policies for tips on how to make the best use of Eng-Tips.
RE: When is a motor just a motor, just a motor?
RE: When is a motor just a motor, just a motor?
Cheers
Greg Locock
SIG:Please see FAQ731-376: Eng-Tips.com Forum Policies for tips on how to make the best use of Eng-Tips.
RE: When is a motor just a motor, just a motor?
Walter Carter, Palm Springs, California
RE: When is a motor just a motor, just a motor?
It seems to have some pretty capable members. Not a lot of theory, but a lot of practical application.
Jay Maechtlen
http://www.laserpubs.com/techcomm