A question that more than one of us might like to know. Will the engine run with the TPS disconnected? If so, does the timing advance still work or does it stay at idle setting? Does the TPS have anything to do with "total" advance or just the advance curve to a given "set" total timing. My understanding is that the TPS box contains the curve only and adjusts the timing relative to the throttle setting. Any comments? Please specify if you are referring to a carb engine or a EFI engine in any of your comments.
TPS Questions
- Thread starter Outbound86
- Start date
From my understanding/experiences:
-engine will run without TPS plugged in
-to check timing with a timing light you unplug TPS
-if I remember right my timing did indeed change with RPM with TPS unplugged while I was checking my timing. (So this would make timing curve RPM dependant in addition to TPS dependant?)
This was on an 04' 800 Polaris (carbed). Hopefully someone else can answer the more difficult questions...
-engine will run without TPS plugged in
-to check timing with a timing light you unplug TPS
-if I remember right my timing did indeed change with RPM with TPS unplugged while I was checking my timing. (So this would make timing curve RPM dependant in addition to TPS dependant?)
This was on an 04' 800 Polaris (carbed). Hopefully someone else can answer the more difficult questions...
T.P.S.
T.P.S is nothing more than an inexpensive "rheostat" it's not an E.C.U. "box"
The E.C.U. controls the timing AND ADVANCE CURVES, (contingent upon R.P.M.and engine temp and DETonation sensor if equipped) not the T.P.S., so the timing will NOT stay where it is at idle.
With the T.P.S. in use, it modifies the timing (if necessary) depending upon throttle position and R.P.M. I thought I remember something about (4) different advance curves being available to the E.C.U.
The T.P.S. gets set at wide open throttle, 4.0-4.1 volts is spec, although I run 4.3 volts
A slightly higher voltage setting places more advance into the engine
IDLE speed has NO impact upon the T.P.S. setting, that's why there's a big old thumb screw there for the idle screw.
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C.F.I. sleds
For an C.F.I. the T.P.S. can actually change the fuel curve either RICH/LEAN depending upon which direction it's off by, and you do need the T.P.S. plugged in to drive the sled.
As the E.C.U. and injectors have NO other way of knowing how much the throttle blades are open.
T.P.S. gets set with at .70 volts throttle blades slammed shut!, then open until .94 or .95 volts is achieved.
A slightly lower voltage LEANS the engine
The idle speed is determined by the voltage, NOT engine R.P.M.
Adjusting the idle speed AFTER the T.P.S. has been set does ALTER the T.P.S. setting and should NOT be messed with AFTER the T.P.S. has been set (that's why there's a small set screw there for idle speed)
FOR CARB ENGINES: ALSO, ALL THE QUESTIONS ANSWERED ABOVE by GoinBoardin' ARE CORRECT^^^^^^^^^^^^^^^^^
T.P.S is nothing more than an inexpensive "rheostat" it's not an E.C.U. "box"
The E.C.U. controls the timing AND ADVANCE CURVES, (contingent upon R.P.M.and engine temp and DETonation sensor if equipped) not the T.P.S., so the timing will NOT stay where it is at idle.
With the T.P.S. in use, it modifies the timing (if necessary) depending upon throttle position and R.P.M. I thought I remember something about (4) different advance curves being available to the E.C.U.
The T.P.S. gets set at wide open throttle, 4.0-4.1 volts is spec, although I run 4.3 volts
A slightly higher voltage setting places more advance into the engine
IDLE speed has NO impact upon the T.P.S. setting, that's why there's a big old thumb screw there for the idle screw.
********************************************************
C.F.I. sleds
For an C.F.I. the T.P.S. can actually change the fuel curve either RICH/LEAN depending upon which direction it's off by, and you do need the T.P.S. plugged in to drive the sled.
As the E.C.U. and injectors have NO other way of knowing how much the throttle blades are open.
T.P.S. gets set with at .70 volts throttle blades slammed shut!, then open until .94 or .95 volts is achieved.
A slightly lower voltage LEANS the engine
The idle speed is determined by the voltage, NOT engine R.P.M.
Adjusting the idle speed AFTER the T.P.S. has been set does ALTER the T.P.S. setting and should NOT be messed with AFTER the T.P.S. has been set (that's why there's a small set screw there for idle speed)
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Thanks guys for the reply -- you answered my questions. About the 4 curves --- I understand that the 2002 Edge CDI box has 4 curves, but the 2003-05 have 16 different curves and as it turned out the boxes from 03-05 did not perform as well. Not sure that the boxes were all the fault because the 03-05 had factory jetting changes as well. The newer box was less timing to stop the possible "rattle" during midrange, but this cost performance. Any comments welcome.
2002 EDGE 800 vs. 2003 800
Comparing the 2002 800 to the 2003 800 (we have both in our fleet) the 2002 had 500 mains (flat lander) and the 2003 had staggered 460/470 mains due to the deficient air box design,
Agreed on less aggressive timing on the 2003 and newer E.C.U. compared to the 2002 E.C.U.
Comparing the 2002 800 to the 2003 800 (we have both in our fleet) the 2002 had 500 mains (flat lander) and the 2003 had staggered 460/470 mains due to the deficient air box design,
Agreed on less aggressive timing on the 2003 and newer E.C.U. compared to the 2002 E.C.U.
Just wondering -- how did the two sleds (02 - 03) compare in performance? Mileage? Throttle response?
2002 compared to 2003 800's
The 2002 and 2003 800's rode over 4000+ miles side / side.
We check the mileage at every fuel stop.
Mostly aggressive groomed trail riding
The 2002 was always faster in acceleration and top speed.
Mileage was almost identical, with the 2003 being ever so slightly better at times.
10-11 M.P.G. was the norm prior to the ATAAC. Riding E-Z, mileage improved to 12+M.P.G. with the ATAAC, on both of these and on another 2002 800 that rides in a different group.
The 2002 was noticeably more responsive/crisper, but to be fair, I jetted the 2002 down from 500 mains stock to 480's when it was brand new. The 2003 retained the stock staggered jetting.
After a couple of seasons, we installed the ATAAC's, and the 2002 was still crisper.
I sold the 2002 at 6400+ miles, (.0025" crank run-out at the time) my bud still has the 2003, 4500+ miles,(never broke down, spark plugs and go) only .0015" crank run-out.
Until I rode my D7, I felt that EDGE was one of the best sleds I ever had.
And I wish my CFI D7 was as crisp and responsive as my old EDGE 800.
The 2002 and 2003 800's rode over 4000+ miles side / side.
We check the mileage at every fuel stop.
Mostly aggressive groomed trail riding
The 2002 was always faster in acceleration and top speed.
Mileage was almost identical, with the 2003 being ever so slightly better at times.
10-11 M.P.G. was the norm prior to the ATAAC. Riding E-Z, mileage improved to 12+M.P.G. with the ATAAC, on both of these and on another 2002 800 that rides in a different group.
The 2002 was noticeably more responsive/crisper, but to be fair, I jetted the 2002 down from 500 mains stock to 480's when it was brand new. The 2003 retained the stock staggered jetting.
After a couple of seasons, we installed the ATAAC's, and the 2002 was still crisper.
I sold the 2002 at 6400+ miles, (.0025" crank run-out at the time) my bud still has the 2003, 4500+ miles,(never broke down, spark plugs and go) only .0015" crank run-out.
Until I rode my D7, I felt that EDGE was one of the best sleds I ever had.
And I wish my CFI D7 was as crisp and responsive as my old EDGE 800.
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I have seen the 02 ECU boxes on ebay and they go pretty cheap -- I think you could use the 700 or 800 box. Everything that I have read seems to point to the 02 box having a better spark curve for performance. I have not been involved in a given test, but seems to be the general understanding on the forums. Maybe someone will jump in that knows for sure from testing.
The stock mains are 500's (I ran 480's at 1200') for the 2002 and the needles on an '03 are different as well.
I see you're in Minnesota, so I would start with 480's and watch the plugs and wash and let that guide your decision from there
