T-leg Piggyback ECU R&D
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- Fourth Gear
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- Third Gear
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- Fifth Gear
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I want my shop.... working out of a hotel room is not very productive.
I've got a reservation for a week-long rental of a huge Caterpillar 420 front-end loader / backhoe to clear and level my new 2-acre lot, and will be able to begin building the real shop there. This new land is already surveyed, has a clear title, and has power lines just two blocks away. The old land was in an area that had all kinds of survey problems and we just couldn't get anything done there.
I can't wait to have a real workshop again!!
I've got a reservation for a week-long rental of a huge Caterpillar 420 front-end loader / backhoe to clear and level my new 2-acre lot, and will be able to begin building the real shop there. This new land is already surveyed, has a clear title, and has power lines just two blocks away. The old land was in an area that had all kinds of survey problems and we just couldn't get anything done there.
I can't wait to have a real workshop again!!
-Chris
91SS 4EAT stock
91SS 5MT awaiting engine rebuild and VF36...
92SS 4EAT - RIP
94SS 5MT4.11+rLSD 289k km: RobTune550,TD05-16g @ 18psi,FMIC,3"TBE,Forester lift
91SS 4EAT stock
91SS 5MT awaiting engine rebuild and VF36...
92SS 4EAT - RIP
94SS 5MT4.11+rLSD 289k km: RobTune550,TD05-16g @ 18psi,FMIC,3"TBE,Forester lift
I really wonder if the comments he mentioned about unshielded wire could be a cause for some of my issues with the extension harness I have the PP hooked up to.
Josh
surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT
If you need to get a hold of me please email me rather then pm
surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT
If you need to get a hold of me please email me rather then pm
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- Fifth Gear
- Posts: 2266
- Joined: Wed Nov 12, 2003 12:26 am
- Location: USA: Portland, OR (Tigard, ~200ft elevation)
- Contact:
Josh,
I've definately found that every signal you want to run somewhere has to be in it's own, separately-shielded wire (not sharing a shield with other signals) to avoid signal bleeding. Also, if the PP doesn't buffer it's inputs, you'd need an op-amp at each point you're taking a signal from (unless you grab them from the ECU, where they should already be buffered)...
I've definately found that every signal you want to run somewhere has to be in it's own, separately-shielded wire (not sharing a shield with other signals) to avoid signal bleeding. Also, if the PP doesn't buffer it's inputs, you'd need an op-amp at each point you're taking a signal from (unless you grab them from the ECU, where they should already be buffered)...
-Chris
91SS 4EAT stock
91SS 5MT awaiting engine rebuild and VF36...
92SS 4EAT - RIP
94SS 5MT4.11+rLSD 289k km: RobTune550,TD05-16g @ 18psi,FMIC,3"TBE,Forester lift
91SS 4EAT stock
91SS 5MT awaiting engine rebuild and VF36...
92SS 4EAT - RIP
94SS 5MT4.11+rLSD 289k km: RobTune550,TD05-16g @ 18psi,FMIC,3"TBE,Forester lift
Hmm....does the shielded wire need to be grounded?
I do not know if the PP buffers inputs. It is something I can ask. Can you provide a little more detail so I can intelligently ask the question and provide feedback if asked a question?
Thanks
I do not know if the PP buffers inputs. It is something I can ask. Can you provide a little more detail so I can intelligently ask the question and provide feedback if asked a question?
Thanks
Josh
surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT
If you need to get a hold of me please email me rather then pm
surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT
If you need to get a hold of me please email me rather then pm
Other question is regarding the harness Vikash made.
http://www.main.experiencetherave.com:8 ... fectpower/
Do you think having the wiring the way it is could be causing some of my issues?
http://www.main.experiencetherave.com:8 ... fectpower/
Do you think having the wiring the way it is could be causing some of my issues?
Josh
surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT
If you need to get a hold of me please email me rather then pm
surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT
If you need to get a hold of me please email me rather then pm
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- Fifth Gear
- Posts: 2266
- Joined: Wed Nov 12, 2003 12:26 am
- Location: USA: Portland, OR (Tigard, ~200ft elevation)
- Contact:
Yep, the shields of each signal wire should be grounded to the chassis somewheres.
Since you're taking those signals from the ECU though, it probably wouldn't be an issue. If you were taking the signals from the actual sensors themselves and running cables through the firewall then shielding would be a good idea.
To guarantee that connecting the signals to additional inputs doesn't draw the signal levels down at all, each signal should optimally have an op-amp in line for protection. May or may not be necessary depending on the hardware they used, may or may not be necessary on the LegacEBC but I'll probably do it anyway to ensure that sort of thing won't be an issue.
Since you're taking those signals from the ECU though, it probably wouldn't be an issue. If you were taking the signals from the actual sensors themselves and running cables through the firewall then shielding would be a good idea.
To guarantee that connecting the signals to additional inputs doesn't draw the signal levels down at all, each signal should optimally have an op-amp in line for protection. May or may not be necessary depending on the hardware they used, may or may not be necessary on the LegacEBC but I'll probably do it anyway to ensure that sort of thing won't be an issue.
-Chris
91SS 4EAT stock
91SS 5MT awaiting engine rebuild and VF36...
92SS 4EAT - RIP
94SS 5MT4.11+rLSD 289k km: RobTune550,TD05-16g @ 18psi,FMIC,3"TBE,Forester lift
91SS 4EAT stock
91SS 5MT awaiting engine rebuild and VF36...
92SS 4EAT - RIP
94SS 5MT4.11+rLSD 289k km: RobTune550,TD05-16g @ 18psi,FMIC,3"TBE,Forester lift
I am tapping off that harness near/right at the ECU for the PP leads. So you don't think that harness or the PP wiring needs to be shielded?
Josh
surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT
If you need to get a hold of me please email me rather then pm
surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT
If you need to get a hold of me please email me rather then pm
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- Fifth Gear
- Posts: 2266
- Joined: Wed Nov 12, 2003 12:26 am
- Location: USA: Portland, OR (Tigard, ~200ft elevation)
- Contact:
I wouldn't think so, no. The leads aren't very long, are they? If you're moving signals any more than a few feet there will be some drop, not sure how much would be acceptable in this application.
I might be wrong though - I still haven't used any signals directly from the ECU so I don't have direct experience just yet. I hate not having my shop yet
I suppose if you've got a digital voltmeter so you can see small changes, you can measure each signal in relation to ground with the key on (engine off so they don't fluctuate) at the ECU and at the PP, and see if there are any noticable differences. That might give us some clue as to which signals are problematic, if any.
I might be wrong though - I still haven't used any signals directly from the ECU so I don't have direct experience just yet. I hate not having my shop yet
I suppose if you've got a digital voltmeter so you can see small changes, you can measure each signal in relation to ground with the key on (engine off so they don't fluctuate) at the ECU and at the PP, and see if there are any noticable differences. That might give us some clue as to which signals are problematic, if any.
-Chris
91SS 4EAT stock
91SS 5MT awaiting engine rebuild and VF36...
92SS 4EAT - RIP
94SS 5MT4.11+rLSD 289k km: RobTune550,TD05-16g @ 18psi,FMIC,3"TBE,Forester lift
91SS 4EAT stock
91SS 5MT awaiting engine rebuild and VF36...
92SS 4EAT - RIP
94SS 5MT4.11+rLSD 289k km: RobTune550,TD05-16g @ 18psi,FMIC,3"TBE,Forester lift
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- Fifth Gear
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are there any updates on the legaCU or the legaEBC? this thead can't be dead. it is what inspired me to join here.
93 legacy wagon L, 22T swapped (TW imitator) now with five forward speeds. (Gone, but never forgotten)
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