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Wiring/Computer related question for 350 swap

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Old Apr 2, 2020 | 03:53 PM
  #1  
Moonan55's Avatar
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From: Connecticut
Car: 1985 Chevy Camaro Sport Coupe
Engine: Chevy 350 w/ Vortec heads
Transmission: 700R-4
Axle/Gears: Stock 2.73
Wiring/Computer related question for 350 swap

Hi, I was wondering if I could get some answers cleared up for a few things. I have an 85 camaro which currently has a 305 with a cc quadrajet in it which is mated to 700r4. Well the motor recently took a dump and instead of pouring more money into it I decided im gonna swap a 350 in it. I want as little electronics in this thing as possible, just a carbed setup, nothing fancy, nice and simple. I understand the 700r4 needs the computer for the lockup. So here's my questions:

-If I were to not touch the computer at all and just take the engine wiring harness and route it into the inner fender and only pull the wires I need (gauge wires, grounds, etc. No sensors) would that cause the computer to not work properly? If I did this would I have to keep all the stock ignition stuff? What other problems (besides a check engine light) could this potentially cause?

-If I kept the 700r4 lockup plugged into the computer would it shift properly? does it rely on other components such as the tach?

The reason for my asking is because it would be a lot easier and cheaper to do it this way so I wouldn't have to wire a solenoid to the tranny, and that way I can keep the stock wiring if I ever want to go back to the stock setup. Im on a tight budget, so im willing to save as much dough as possible. It should also be noted that im getting rid of all the smog stuff and the air pump, along with the computer controlled quadrajet so that might cause the computer to act wonky. These old computer systems are so primitive that I feel like if you take one thing away, everything else catches on fire lol. Thanks for any help
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Old Apr 2, 2020 | 04:10 PM
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Re: Wiring/Computer related question for 350 swap

You'll spend as much money eliminating stock components as you'd spend swapping the existing carb/distributor into the 350. If the carb works on the 305 it'll work on a 350.
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Old Apr 2, 2020 | 04:39 PM
  #3  
Moonan55's Avatar
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From: Connecticut
Car: 1985 Chevy Camaro Sport Coupe
Engine: Chevy 350 w/ Vortec heads
Transmission: 700R-4
Axle/Gears: Stock 2.73
Re: Wiring/Computer related question for 350 swap

Originally Posted by Drew
You'll spend as much money eliminating stock components as you'd spend swapping the existing carb/distributor into the 350. If the carb works on the 305 it'll work on a 350.
The carb barely works on the 305. Just gonna get a mechanical quadrajet for it. So I would have to keep the stock distributer in order to keep the 700r4 lockup running with the computer? I might as well just take the computer out completely and get a lockup switch. I really hate wiring though lol. If I take it out completely I would need a new wiring harness correct? Sorry for these dumb questions I've never swapped a motor before
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Old Apr 2, 2020 | 08:03 PM
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Car: '83 Firebird (T/A Clone)
Engine: 350 with L-69 components
Transmission: 700R-4, 2000 RPM stall converter
Axle/Gears: 10-bolt/3.73 ..
Re: Wiring/Computer related question for 350 swap

Originally Posted by Moonan55
The carb barely works on the 305. Just gonna get a mechanical quadrajet for it. So I would have to keep the stock distributer in order to keep the 700r4 lockup running with the computer? I might as well just take the computer out completely and get a lockup switch. I really hate wiring though lol. If I take it out completely I would need a new wiring harness correct? Sorry for these dumb questions I've never swapped a motor before
The computer operates and/or monitors the emission control equipment, so if you are keeping all that, stick with the cc carb and distributor.
On my '83, I removed all the emissions stuff except for the cat. Took out the wiring harness for the computer (passenger side), and installed a non-cc quadrajet, a vacuum advance HEI distributor, and a non-computer lock-up kit for the torque converter. Just using the main engine wire harness from the driver side of the firewall...
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Old Apr 2, 2020 | 09:21 PM
  #5  
Moonan55's Avatar
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From: Connecticut
Car: 1985 Chevy Camaro Sport Coupe
Engine: Chevy 350 w/ Vortec heads
Transmission: 700R-4
Axle/Gears: Stock 2.73
Re: Wiring/Computer related question for 350 swap

Originally Posted by T.L.
The computer operates and/or monitors the emission control equipment, so if you are keeping all that, stick with the cc carb and distributor.
On my '83, I removed all the emissions stuff except for the cat. Took out the wiring harness for the computer (passenger side), and installed a non-cc quadrajet, a vacuum advance HEI distributor, and a non-computer lock-up kit for the torque converter. Just using the main engine wire harness from the driver side of the firewall...
Yeah that's probably the route I'm gonna take as well, I don't want any emissions stuff. Plus a previous owner already cut the cat and messed with all the vacuum lines... Thanks for clearing stuff up
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Old Apr 2, 2020 | 10:29 PM
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Re: Wiring/Computer related question for 350 swap

If the system is already horqued, the easy route is a non-computer Qjet and a vacuum advance distributor. Tie all the old wiring out of the way where it won't get into anything that moves or gets hot, and drive on. It looks a bit tacky with all the wires tied off, but it works.
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Old Apr 3, 2020 | 10:13 AM
  #7  
Moonan55's Avatar
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From: Connecticut
Car: 1985 Chevy Camaro Sport Coupe
Engine: Chevy 350 w/ Vortec heads
Transmission: 700R-4
Axle/Gears: Stock 2.73
Re: Wiring/Computer related question for 350 swap

Originally Posted by Drew
If the system is already horqued, the easy route is a non-computer Qjet and a vacuum advance distributor. Tie all the old wiring out of the way where it won't get into anything that moves or gets hot, and drive on. It looks a bit tacky with all the wires tied off, but it works.
So basically all the wires on the passenger side aren't needed except the heater blower right? I might just take all those out and sell it on ebay lol, along with the computer. And all the ac stuff. Any $$$ I can scrape out of this boat anchor engine I'll take lol
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Old Apr 3, 2020 | 10:37 AM
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Re: Wiring/Computer related question for 350 swap

The second you cut something out, sell it, etc you'll need it. Deleting the A/C is right up there with cutting the roof off with a sawzall, ie resale suicide.
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Old Apr 3, 2020 | 11:28 AM
  #9  
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From: Connecticut
Car: 1985 Chevy Camaro Sport Coupe
Engine: Chevy 350 w/ Vortec heads
Transmission: 700R-4
Axle/Gears: Stock 2.73
Re: Wiring/Computer related question for 350 swap

Originally Posted by Drew
The second you cut something out, sell it, etc you'll need it. Deleting the A/C is right up there with cutting the roof off with a sawzall, ie resale suicide.
It's funny you say that because one of the previous owners put a sunroof in it. Probably why I got the car so damn cheap lol. It has to be clamped closed a certain way or the rain leaks in. I bought it from the ghetto and it never left that street, every time someone sold it someone a few houses down bought it lol. But I figured if I don't need the parts, someone else might for their build. I get what you're saying though, my closet is full of the stock gauges that came with it, but the speedo shot itself. I don't want to throw it away because if I ever do sell it they might want it.
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