The Definitive "VVT swap into 90-97 chassis" Megathread.
#525
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For those of you looking to step up your wiring game, I stumbled across www.wirebarn.com a week or two ago. They sell multi-color packs of GXL and TXL cross-link automotive wire in sub-spool quantities for really reasonable prices (a few cents more than you would pay for a full 100ft spool).
#526
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Wirebarn is addicting. TXL wire smells and feels amazing. I have soooo much wire from them. I always buy the like 8 pack of colors so all the wiring is the same color on my car. I wish they did striped wire too though.
#531
For those of you looking to step up your wiring game, I stumbled across www.wirebarn.com a week or two ago. They sell multi-color packs of GXL and TXL cross-link automotive wire in sub-spool quantities for really reasonable prices (a few cents more than you would pay for a full 100ft spool).
I'm guessing this is way better wire than what i was using ( hookup wire)
This is our regulator adapter on a VVT fuel rail with an Earl's Vaporguard 1/8" NPT to 5/16" 90deg fitting. The green goo is Gasoila E85 sealant. There's no way to get a standard FPR in this spot with clearance for vac/fuel hookups, but you can get the NPT fitting oriented correctly so it just barely sneaks out of there. This is a good option for people who are going to run an aftermarket FPR (something like a Fuelab 545 would go inline between this and the return line) since you can use the OEM VVT rail that comes on the motor instead of sourcing a combination of US parts or a hard-to-find EUDM 99-00 setup.
Adapter: Trackspeed FPR Adapter
Fuelab 545-series: Fuelab Fuel Pressure Regulator
Well, if only I read this a few months ago..
#532
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TXL/GXL (crosslink) is what OEMs use to wire cars. Milspec is cool but 3x the price. If I were wiring a race car from scratch, then yes, /32 wire is what I'd use. If I'm adding a few dozen wires for a VVT swap setup, then TXL is the correct wire for the application. Hookup wire won't burn the car down but it's not nearly as robust.
#533
TPS:
The 90-93 manual chassis did not originally come with a 0-5v variable TPS. To use a 94-05 0-5v throttle position sensor in a 90-93 chassis, consult with your ECU supplier to confirm the wiring changes that are necessary.
The 1994-1997 chassis did come with a 0-5v variable TPS. It is a standard 3-wire TPS with an additional fourth wire (red) which serves as a wide-open switch. Your standalone ECU will likely not use this fourth wire, so if you are changing the pigtail to a 99-05 style, simply heat-shrink over this unused wire. If you are using your 94-97 throttle body, there are no wiring changes necessary. If you are using the 99-05 sensor, wiring colors are listed below:
5v Reference:
94-05: Light Green/Red (Light Green/White...97)
TPS
The 90-93 manual chassis did not originally come with a 0-5v variable TPS. To use a 94-05 0-5v throttle position sensor in a 90-93 chassis, consult with your ECU supplier to confirm the wiring changes that are necessary.
The 1994-1997 chassis did come with a 0-5v variable TPS. It is a standard 3-wire TPS with an additional fourth wire (red) which serves as a wide-open switch. Your standalone ECU will likely not use this fourth wire, so if you are changing the pigtail to a 99-05 style, simply heat-shrink over this unused wire. If you are using your 94-97 throttle body, there are no wiring changes necessary. If you are using the 99-05 sensor, wiring colors are listed below:
5v Reference:
94-05: Light Green/Red (Light Green/White...97)
TPS
#534
Wiring:
CAS:
You must use the NB cam and crank angle sensors if you want VVT control. There is no way to control the VVT if you use an NA-style CAS driven from the exhaust camshaft.
The OEM 1990-1997 CAS has 4 wires. One wire is +12v, one wire is a sensor ground, and there is a signal wire for the crank position and a signal wire for the cam position. You will need to cut the factory plug off and extend the +12v and ground wires to each of the NB sensors. The cam signal wire will get routed to the camshaft sensor on the top of the valve cover, and the crank signal wire will get routed to the crankshaft sensor located near the harmonic damper. This will bring the appropriate cam and crankshaft patterns along the OEM harness into the ECU, and all of the other changes necessary will happen in the firmware/software of your ECU.
#535
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Okay so I've just finished reading through the thread again, and this still doesn't make sense to me for a 96-97 late NA. Those cars already had crank position sensors, so couldn't you just plug the 01+ sensor into the 96-97 harness and get the signal to the ECU without having to extend the CAS? It's also weird because those cars also have 4 wires for the CAS. From what I read on the interwebs, the CPS was just used to monitor for misfires on the 96-97. That still doesn't explain why you couldn't just plug the 01+ CPS into the 96-97 harness in the stock location (and make the adjustment on the ECU side, if need be), right?
#537
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The '97 has three wires, but the third wire is a shielding ground for the other two. You could theoretically pass 12v up one of them, the signal up the other, and then wire a new ground as well, and then change all the pinning at the ECU, but **** that.
#539
For those of you looking to step up your wiring game, I stumbled across www.wirebarn.com a week or two ago. They sell multi-color packs of GXL and TXL cross-link automotive wire in sub-spool quantities for really reasonable prices (a few cents more than you would pay for a full 100ft spool).
#540
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For your own sanity, it's much better to order 10ft of wire in 10 different colors than it is to wire the entire extension harness in the same color. I order from Delcity, but I also order 10+ colors 100ft each at a time. Enough to do several cars and other projects before I have to think about reordering. If you're doing one car, the multi-color sub-spool Wirebarn packs are the ticket.