The Definitive "VVT swap into 90-97 chassis" Megathread.
#301
Cpt. Slow
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Just finished wiring up a 94 with a '01+ engine harness for cleanness, and plugged in a pnp adapter harness and Hydra 2.7.
Coils according to the first post in this thread were backwards. You can't change the Hydra coil outputs within the software, they have to be wired correctly. Before I dig into the adapter harness to see if it's the issue, has anyone else experienced this? I have brown to brown/white, and brown/yellow to black/yellow.
Also, I went through all the work to install a TSE oil pressure adapter, SS line, and cut/drilled/tapped the upper hard line for a AN-NPT adapter, since I'm putting a VVT head on a 94 block. Did I do all that work for nothing? Am I reading in post #281 that I didn't have to do all that?
Coils according to the first post in this thread were backwards. You can't change the Hydra coil outputs within the software, they have to be wired correctly. Before I dig into the adapter harness to see if it's the issue, has anyone else experienced this? I have brown to brown/white, and brown/yellow to black/yellow.
Also, I went through all the work to install a TSE oil pressure adapter, SS line, and cut/drilled/tapped the upper hard line for a AN-NPT adapter, since I'm putting a VVT head on a 94 block. Did I do all that work for nothing? Am I reading in post #281 that I didn't have to do all that?
#306
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Not sure about the coil wiring but the VVT plumbing works just fine ,no modifications for my swap. I too used a 94 block with a VVT head. No leaks VVT works fine.
Just finished wiring up a 94 with a '01+ engine harness for cleanness, and plugged in a pnp adapter harness and Hydra 2.7.
Coils according to the first post in this thread were backwards. You can't change the Hydra coil outputs within the software, they have to be wired correctly. Before I dig into the adapter harness to see if it's the issue, has anyone else experienced this? I have brown to brown/white, and brown/yellow to black/yellow.
Also, I went through all the work to install a TSE oil pressure adapter, SS line, and cut/drilled/tapped the upper hard line for a AN-NPT adapter, since I'm putting a VVT head on a 94 block. Did I do all that work for nothing? Am I reading in post #281 that I didn't have to do all that?
Coils according to the first post in this thread were backwards. You can't change the Hydra coil outputs within the software, they have to be wired correctly. Before I dig into the adapter harness to see if it's the issue, has anyone else experienced this? I have brown to brown/white, and brown/yellow to black/yellow.
Also, I went through all the work to install a TSE oil pressure adapter, SS line, and cut/drilled/tapped the upper hard line for a AN-NPT adapter, since I'm putting a VVT head on a 94 block. Did I do all that work for nothing? Am I reading in post #281 that I didn't have to do all that?
Last edited by curly; 10-08-2016 at 03:38 PM.
#313
Former Vendor
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Coils according to the first post in this thread were backwards. You can't change the Hydra coil outputs within the software, they have to be wired correctly. Before I dig into the adapter harness to see if it's the issue, has anyone else experienced this? I have brown to brown/white, and brown/yellow to black/yellow.
#314
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But, as an additional data point,
when the '94 oil pressure sender was in the '01 location in the hard line, I noticed oil pressure fluctuations when changing throttle settings. I corolated them to the vvt changing. So I plugged the oem sensor location, welded a AN3 nipple to the end of the banjo bolt, so the sensor would read the pressure in the oil galley and not the hard line. Ran a ss line to the same sensor mounted on the inner fender well. Now rock solid oil pressure indication at any throttle angle. Moral of the story is there is a slight restriction when the oil turns and goes thru the holes in the banjo bolt, enough to cause a slight drop in pressure that can be seen on the oil pressure gauge.
#319
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True, a line might be compliant, but with only 40-60 psi, a stainless braided Teflon line won't absorb the pressure fluctuations. The fluctuations are not pulsation, it is a momentary drop/rise when the vvt valve opens/closes.
A FPD is another animal, used for damping pulses from the injectors opening and closing, a decent description is found HERE.
I was was just stating a problem that I saw and what I did to cure it, take it for what it's worth.
A FPD is another animal, used for damping pulses from the injectors opening and closing, a decent description is found HERE.
I was was just stating a problem that I saw and what I did to cure it, take it for what it's worth.