hypntyz

There's no way I am resizing hundreds of pics for some guys on an internet forum. They can take it or leave it, I've done enough work by writing and posting all this to begin with. IF the forum auto-resize feature isn't good enough, then I'm sorry, they can muddle their way through their own swaps without any help they might garner from this thread. They can also set the forum to show only 5 posts per page in user settings which will limit how many pics are loaded at one time.

hypntyz

What was most disheartening about the harness was that there was a huge group of unterminated wires hanging off one end of it. Many were labeled, a few were not (I suspect the labels fell off). I realized that this harness was going to be nowhere near as "plug and play" as I had hoped (and paid for). What was much worse though, was the fact that there were basically NO INSTRUCTIONS OR GUIDELINES for completing these connections. The only thing included with the harness was a group of sheets which were wiring schematics. No mention of where to find each relay, or each described junction block, etc.










I was looking at all this in disbelief thinking "WTF, why do I still have to figure out all this crap after paying this guy $850!". If I had wanted to spend hours and weeks poring over wiring diagrams and searching the FSM for "junction block C100 pin D" then I could have damn sure saved 3 or 400 bucks and modified a stock harness or a cheap painless harness. It's not even that I am not capable---I run a fulltime shop and am able to look at the diagrams and figure them out---but this is not really what I asked for nor what I paid extra for. It would have been SO much better if there had been a general guideline sheet to go by...and since Vettaid is supposed to be a corvette specialist, I see no reason why he could not include this info.

Something like "locate the C100 wiring junction block behind the battery on the firewall, remove plastic covering and locate the 8mm bolt in the center to loosen the plug. Once separated, remove pin 1E from C100 and insert the pink wire from the Vettaid harness" etc. for each unterminated wire connection required would have been nice. But no, there was none of that, I had to look at those random drawings and then cross reference that with the 85 FSM to find the location of the part, wire, plug, or junction and then go to the car and physically find it, figure out each wire, one by one, then cut, solder, and heat shrink.

This work took MONTHS because I only had an hour or two per week to work on the swap, and the very thought of having to figure out and research all these connections infuriated me each time I tried to start on it. I could have done the work in a week, had I received basic help and instruction. I specialize in certain mazda cars too, and I've posted more information for free on my website to help people than he gave me with an almost-$2000 parts order (counting the headers etc.).

Instead, I took written notes of each connection I had to locate and change as I went along, and I now have 5 full pages of detailed information about how to locate make each connection. Maybe I'll sell it to Vettaid to include for his future harness customers, and recoup some of my lost time.

hypntyz

Here is an example. Behind the battery and under the clutch master cylinder is the major wiring junction C100. This is the firewall pass-through for most of the functions of the car except the factory fuel injection. The plug on the engine-bay-side is covered with a plastic shield and held onto the block by a bolt in the middle of the wiring cluster that is impossible to see if you don't know it's there already.

So it literally took me hours to figure out how to get the connector apart, by researching in the FSM and more research online. I found this forum to be devoid of information on C100, however camaros and other 80's GM cars share this type of connector so I was able to find more info on a camaro forum. Once you do separate the plug, you find that all the wires and connections are covered in this black tar-like substance. Apparently this was a conductor put on by the factory to prevent corrosion etc. but it has now changed composition. It took hours of scrubbing with fine brushes and many cans of brake parts cleaner to expose the connections.






The connector actually comes apart in halves...



Then to remove wires you have to find and remove this retainer.



I was supposed to remove a major wire from the factory connector and install one of the vettaid harness wires into the connector instead. Here's the stock wire removed...




And here's a comparison with the vettaid wire I was supposed to install. Obviously this is not going to work.

hypntyz

So, here is what I had to do, cut the vettaid connector off it's wire, cut the original connector off the original wire, and solder/heatshrink the original connector onto the vettaid wire so that it could be properly installed into the C100 connector plug.








Here I have done the same for another of the vettaid wires.



And making a couple more wire swaps in this connector.

hypntyz

I had to de-loom one of the remaining wiring harness in the engine bay and trace the leftover stock wires that were not being reused, so that they could be removed.



For example, these stock wires used to run from the distributor to C100 to feed the dash a tach signal (IIRC), and now they aren't used so I removed them.




Same for this alternator field wire set.



And one of the main power wires that used to connect to B+ at the starter that's no longer used.

hypntyz

For each of the two fan control relays (my 85 has the primary fan on the radiator and a secondary aux fan in front of the condenser) plus the fuel pump relay, I had to locate each relay, locate a specific wire on each relay, cut it a couple of inches below the relay, and solder on a vettaid control wire to actuate that relay. Here is the primary cooling fan control relay being rewired.







Here is the secondary fan control relay behind the battery, the same procedure had to be done to it.







The fuel pump relay on my car was located between the wiper motor and the throttle cable etc. bolted to a hole on the driver side of the firewall behind the engine. Both my relay and my wiring connector seemed really suspect, and once I had modified the wiring connection to the relay I had problems verifying that the relay was working.




So I eventually decided to abandon that relay altogether and use a relay from an 86-91 mazda rx7 which would work exactly the same way (still a 5 wire connector) but seemed much more reliable and solid. I traced the wires for the fuel pump relay and moved them all inside the car and placed the relay there.

hypntyz

Here is another wire on the vettaid harness that seemed wrong to me. It's apparently a main power supply wire. It came with an eyelet/ring terminal soldered on. It is supposed to hook to the battery positive post. Clearly this isn't going to work, there's no way to hook it up.



So I had to do it the hard way.

hypntyz

I wanted to mount my LS PCM in the engine bay just like the 92-96 models. so I bought one of those PCM mounting trays. The PCM's are shaped a bit differently so I had to modify and trim the late C4 PCM tray to hold the C5 PCM. I also had to modify the C5 PCM a bit too. For now, the PCM just lays in place in the tray with no lid or clamps, but with the hood shut there is only about half an inch of space so it's not as though it can go anywhere.






The vettaid harness comes with this fuse block that's meant to be mounted nearby. I wanted it accessible but also cleanly out of the way, so I modified it slightly to attach to the bottom of the PCM tray.

hypntyz

I had to hook up the reverse lights manually, and make/modify a wiring connector to fit the stock plug. I believe that's the green wire with the red connector. The other two wires going to a common connector carry 12v+ power to the backup light switch (to power the reverse light circuit when the switch "makes") and to the reverse lockout solenoid (again to actuate the solenoid when the PCM triggers the ground to make the solenoid release). The LS PCM supplies ground to the solenoid anytime the vehicle speed is <3mph to allow you to shift into reverse, without the worry of accidentally hitting R instead of 5 at highway speeds when the solenoid is turned off/locked out.




The vettaid harness came with a tachometer adapter box from Dakota Digital, to convert the LS PCM tach output to a signal the C4 dash can use. I bought a matching Dakota Digital speed signal adapter box to do the same thing for the speedometer, since the C4 dash could not operate off the signal fed from the LS PCM. Since the boxes are identical in size, I just ziptied them together. All of this later got stuffed up in the passenger side dash above the "hush

panel".

hypntyz

Once the car was running and driving, I had to do something about the big hole I had cut for the shifter. So I got a small fiberglass kit and filled in some of the open area with fiberglass, leaving myself just enough room to remove the T56 shifter for repair/etc. should I ever have to service it.

But I still needed some sort of insulating boot to keep hot air and fumes out of the cabin. This was kind of hard to find because the shifter shape is long and skinny, and it also needed to be flexible at the top since my shifter was offset to the left and backward, and also had that extra bolt welded in for support. I bought a 4wd transfer case boot from a chevy tracker (I think) and it seemed to fit pretty well. IT was quite thick and should last forever and keep hot air out.





I had a custom shift boot made by redline performance, but I needed a way to hold the top ring of the boot up flush against the bottom of the shift ****. So I put a spring around the shifter and opened the top of the spring up to fit inside the boot. This way the boot can never ride down the shifter no matter what gear it is in.

hypntyz

For the shift **** I spent a little extra cash and went with a C6 alacantra **** and had it modified for the Fbody shifter threads. Then I had the matching shift boot and e-brake boots made by redline goods (a forum vendor). I couldn't be happer with their quality and appearance.

hypntyz

Here are some pics of the swap as it sits now, mostly finished except for the inevitable details such as a/c and cruise actuation which I still have to figure out. I've put a couple hundred miles of mostly city driving on it and it runs

great, although the tune could use a bit of driveability tweaking due to the cam.

hypntyz

Here's a vid of first startup in the garage.



Another just after I rolled it outside.



A video of a quick pull on an on-ramp.



And a short one of just cruising on the highway in 6th. As you can see all the gauges work accurately except the MPG calculator.

mrmtrtrnd

The car looks and sounds amazing and I can only imagine how it preforms. The swap is hard for me to even wrap my head around there is so much that needs to be changed or customized. Very interesting read and thanks for taking the time to put all that info together.

hypntyz

Bear in mind that mine makes it look harder than it really is because I not only did the LS swap but I did an auto to manual swap at the same time. IF you keep your existing trans and rear the same, the work is greatly reduced.

With the correct parts picked out in advance, I could do another LS engine-only swap in a month or less.

Fastime

Great job I hope you can re-size the pics so I can see them all.

85MikeTPI

The pics stopped loading for me after the second post

We'll have to start organizing a C4-LS swap get together for next year..

Great job on the swap!

hypntyz

Go into your usercp and options, then change posts per page to 5. Now go back and refresh the thread.

If a mod or a user with more time wants to come up with a quick way to reformat the thread then more power to you...when you're done give me the file and I'll delete this thread and repost yours. I've spent enough time on this already, probably 3 or 4 hours at least writing it all up and inserting the pics in the right places.

I thought I'd be getting complaints about lack of videos, track times or dyno sheets, rather than complaints about pictures. I thought we were in 2013 instead of 1995. Do you guys use AOL 56k and view the forum on 15" CRT monitors still?

Tom400CFI

This is a fantastic thread, with incredibly good documentation of the swap. Thank you so much for the contribution! one of the best threads that I've read on here lately.

Now...let's see how it does at the drag track! Car ought to be able to go into the 11's.

Tom400CFI

Just one question; "from an '05 Corvette Z06"...what's with the flex plate?