Planning a 5.3 Swap; Have several questions!

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C10man

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So, im planning to drop a 5.3 or 6.0 into my 86 c10. I know im going to be running the original 700r with a adapter flexplate and spacer, ported heads, cam upgrade, headers, and probably a stock truck intake. Here is where the questions start...

What is the most painless (and fairly cheap) way to run the ignition?
How can I make A/C and power steering work with the newer motor?
How can I control the older trans shifting?
Is there anything I need to be aware of that will bone me with what I have planned?
 

C10man

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Also, I want to replace my stock gas gauge (the big one next to the speedo in the original cluster) with a tach and relocate that gas gauge to where the clock is. Anybody out he tried this or something similar or should I just suck it up and put one of those huge ugly tachs on my column?
 

ajd89

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Also, I want to replace my stock gas gauge (the big one next to the speedo in the original cluster) with a tach and relocate that gas gauge to where the clock is. Anybody out he tried this or something similar or should I just suck it up and put one of those huge ugly tachs on my column?
If you cant find a factory tach gmsports sells them or lmc
 

Crispy

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In regards to the 700R4, if you are going with a drive be cable setup then they sell bracketry to connect a TV cable to the LS throttle body. When it comes to drive by wire I'm not 100% sure. Why are you keeping the 700r4? The LS harness is already set up to control a 4L60E and you can find them everywhere now a days. If you do go with a 4l60E youll have to convert the mechanical speedo to a VSS signal, or get aftermarket gauges, or not have a speedo.

AC is a whole nother can of worm$$$. Do you have factory AC?

Power steering is pretty easy. You can use your existing lines with adapters the LS style thread. I've seen swaps where people claim the lines bolted right up. So try that first. They also sell custom hoses to marry the two for around $150 depending on your budget.

I've seen people run the factory tach. This is a nice OEM solution available to you since you fall within the year compatibility. Aftermarket gauges can get pricey. Like almost as much as your engine pricey.
http://www.73-87.com/7387garage/interior/factory tachometers.htm

What are you planning to do for a fuel system?
 

smurfasaur

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So, im planning to drop a 5.3 or 6.0 into my 86 c10. I know im going to be running the original 700r with a adapter flexplate and spacer, ported heads, cam upgrade, headers, and probably a stock truck intake. Here is where the questions start...

What is the most painless (and fairly cheap) way to run the ignition?
How can I make A/C and power steering work with the newer motor?
How can I control the older trans shifting?
Is there anything I need to be aware of that will bone me with what I have planned?

Definitely not the most knowledgeable source on this stuff but here goes:

If you want painless and fairly cheap I would say having someone rework your stock harness for you and reflash your computer would be the cheapest and easiest. I want to say I’ve seen a guy that will do both for $300 and his work looks nice.

A/C most people buy a high mount bracket from Holley, dirty dingo, etc. Agearhead4life on YouTube has done it in the stock location but it’s real tight.

Power steering most seem to use the stock LS pump with factory c/k lines. Or get custom ones made

700r4 shifting is controlled via TV cable. I don’t know how you do it with an LS swap but I know it can be done. I’d advise searching “ls swap 700r4” you should find what you need

The only thing I would advise is if you’re planning on ported heads, a cam, and headers, also do stiffer valve springs and make sure your tranny can handle 400+ hp because that’s probably what you’ll have with that combo. And I know everyone says this but try to find a low mile, running pullout with all the accessories and harness - your life will be made much easier.


Sent from my iPhone using Tapatalk
 

Derrick

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as a person with a 5.3 truck factory, i can tell you the pros and cons of it in my case I only have 120,000 miles on the truck and so far with regular maintenance, the truck runs greats. now for the cons, the wiring the truck uses is like looking at spaghetti for me so, I would take the wiring to a shop or if you have the time and patience you could go with painless http://www.painlessperformance.com/webcatalog/lstruck . also i would go with 4l60e you can get them out of your donor truck if that is how you are getting the engine, hell you could even take the wiring harness out of your donor truck
 

C10man

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Thanks for all the tips. In response to a few questions, I have a shift kit for a 700r4 from TCI that a friend of mine gave me and I wanted to keep the tranny anyway just because I wont have to mess with anything with the shifter column so that would be one less thing to worry about when swapping and I think it will be cheaper to go that route. I do have factory A/C, and I have had a few different ideas for the fuel system. The one I think would be the coolest is to use a stock single tank (which I believe was a 20 gallon) and put an in tank fuel pump. Then custom make a fuel neck to go to both fuel doors so I can still fill up the truck from either side (the truck came from the factory with dual tanks.) I can bend all the pipes and lines I need at work and I can do the power steering lines too if need be.
 

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