New guy with a Fitech 70051
Just about to install a 5.3 in my 78 Blazer. Glad I found this forum, especially all the posts from. Ill surely be in here asking questions and will post about my install in hopes that it will help someone else some day.
My truck is a 78 Blazer that was originally a 350/350/np203. Im installing the 70051 on an LM7 5.3 crate motor from Summit. Using the Summit fabricated intake manifold and Holley LS swap accessory drive system 20-137. Trans is an NV4500. I got the harness with the auto trans control before deciding to swap to manual so Ill just leave out the trans harness.
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Wont let me edit the post, I was trying to tag @paul-bell in the first sentence.
Mike, do you have a question?
Quote from Paul Bell on December 16, 2023, 7:40 pmMike, do you have a question?
Not yet! Apologies for tagging you a bunch if you got multiple prompts. The edit function did not seem to be working correctly. I was simply trying to introduce myself and give you props for all the great info you've provided. I'll be installing my Fitech system in the next week or so and Im sure I'll have questions then.
Alright Ive finally started wiring. I have a few questions that someone can hopefully help with. First is the alternator. My truck had a 3 wire alternator stock. One power wire coming off the stud on the back of the alternator that goes to a power distribution block. Then a plug with 2 wires, red and brown. The red wire went to the power distribution block and from there to the firewall junction box. The two red wires actually connected in the middle before going on to their respective places. The brown wire went straight into the firewall junction box. My understanding of the red wire in the plug of the old alternator is the voltage detection lead that tells the alternator how much to charge the battery. Do I need this connected in addition to the EFI harness or is that taken care of by one of the wires on the new alternator plug?
The brown wire is the exciter that goes to the firewall junction box and ultimately to an ignition source which tells the alternator to start charging. Do I need this wire with the EFI harness?
On the new alternator Im planning to run a wire from the stud to the battery. Im also planning to run a wire from the battery to the distribution block and run the red wire from the firewall junction box(the old voltage detection lead) to the distribution block so the cab has constant 12v.
Lastly, if I want the stock volt meter to work correctly, which wire is the correct one to connect to?
@paul-bell if you are able to answer any of the questions above that would be excellent. Ive also come up with a coupe more after staring at the harness for a while.
- If im running a manual trans do I need the VSS plug to be connected to anything?
- Can I ghost tap one of the CTS wires so my stock water temp gauge works? If so which one?
Edited because duplicate post.
Edited because duplicate post.
Edited because duplicate post.
Edited because duplicate post.