Hello all, I'm somewhat new to the Corvette, as well as mechanical swaps in any capacity. I've found myself in ownership of an 84 automatic I ended up purchasing last summer. I'm looking to LS swap it and perhaps swap in a different transmission but I don't know what I need or how anything fits.


LS swap side:
I'm not sure how well one would fit and how it would play in. I may go the route of either a 5.3 or 5.7, whatever finds itself to be readily available near me and affordable. I don't know how these play together and what I may need, both in terms of conversions and the electrical side of things as Id like to keep it relatively simple on myself. Anyone who has done this, any input would be greatly appreciated.

4L60:
I don't know how well one will fit? I've heard numerous things about using a tail shaft adapter and VSS stuff but I admittedly don't really know how any of that plays together. Does one fit well, is there anything I should know? Will an aftermarket shift controller be required or do I run with a tuned PCM from a car with a 5.3 and wire it into place? Again, any help would be greatly appreciated. Thank you

 

There a couple c4 ls swap groups on fb. Tons of info.

 

I LS swapped my 84 a long time ago. I started out with a LS6 and a 4L60e and then upgraded to a built 6.0L with a 4L80e. There are several YouTube videos showing how people did these swaps in early C4's. Also search the forum there are tons of build threads showing how people did it. I will say though that lately the forum search function hasn't been working very well. So just use Google. Type in something like "Corvette forum LS swap" and see what you get.

A couple things I would say that will make this much easier for you. Can you weld? Do you own a small welder? If the answer to either of those questions is no then fix that first. You don't need to be a pro just be able to make a basic weld. Also decide how you want to control the motor and trans. GM PCM and harness or aftermarket? If going GM you need HPTuners and a lot of wiring skills. By the time you buy or modify a stock harness and purchase HPTuners your getting close to the price of a Holley Terminator X max ECU that comes with a harness. And the Holley for example is very easy to learn as apposed to HPTuners that has a steep learning curve.

Just some food for thought.

 

How well does the Holley Terminator X work with all C4 dashes, guages?
I would highly recommend putting a Dana 44 with 3.45/3.54 gears and get your suspension/brakes in order prior to going from 245HP to close to 500hp

 

The Terminator has outputs that you can use for things like gauges....but. The signal that comes out of the Terminator is NPN or also called sinking. This means that it pulses ground instead of a +5vdc, +12vdc or a sign wave type signal. That means more than likely your factory gauges (and most aftermarket ones) won't be able to read that signal. This isn't a big deal though. A simple voltage divide circuit will correct this. But to get it to run factory gauges is a lot of work and know how. For me I couldn't get rid of the factory cluster fast enough. I sold it off and used the money to by aftermarket. Intelitronix even has a direct fit cluster for early C4's. I started off with a cheap ebay set of gauges and wasn't happy with it. So I upgraded to Intelitronix round gauges. But the only gauges I have the ECU operate are the tach and warning leds on the dash. Everything else I have separate sending units for or I use the Holley touch screen to display anything I want like knock percentage, fuel pressure and ethanol content. (I run flex fuel) That screen is included with the Terminator.

It's a lot of money but one way you could go is to buy the Holley digital dash. It plugs into the Terminator CAN connector so it doesn't use any inputs or outputs. You can really configure that thing to look however you want and it's a touch screen. But it's expensive.

I completely agree on the gear swap. The higher RPM of even a stock LS is going to love more gear. I kinda feel that in a street car 400 crank HP is a good rule of thumb with street tires as to if you want to swap out the rear for a Dana 44 or not. I swapped mine out with one I bought from a forum member years ago. The guy already had 3.73's installed so I got pretty lucky. But even if you want a mild LS and want to keep the Dana 36 a gear swap is a really good idea. Also don't forget with an LS if you are going with a bigger cam you really need a new converter also. If you don't want to spend a lot the factory 4.2L Trailblazer converter will work as a great budget upgrade over the V8 converter but only for a mild cam.

If you want to upgrade stuff down the road the Holley is really the best option. Over the years I changed engines, cams, swapped to a 4L80e, added progressive nitrous, changed to flex fuel...etc. All of these things were easy and I did the tuning myself. I couldn't have done any of that with HPTuners. But if you KNOW that you're just going to do this once and never change anything then a GM PCM with a good solid tune is the way to go.

 

I did a LS swap over 10 years ago, you can still use the factory gauges as long as use the factory correct sending units. I've went from a Ls factory harness to an after market harness and ECU to a Holley terminator X Max with Autometer gauges. You don't a an ECU all of the gauges EXCEPT for the speedometer, it has to read a pulse from the VSS to work. for the temp gauge I had a factory sending unit milled down an threaded. I had the factory in before the Autometer gauges. But as mention the Holley is the best way to go, oh yea you will loss you mpg gauge. At first I did weld and thing doing the swap, but as time went on that changed.
Randy