Low hanging fruit to improve performance - request for input

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Jeff Heller

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Recently inherited my grandfather's 1981 2WD Custom Deluxe. Before I get into cosmetic repairs/upgrades, I want to improve the performance and reliability. I've never owned a carbureted vehicle before. So far, it hasn't given me any issues. Hasn't quit on me yet and starts right up (with a little priming of the gas pedal when cold).

I'm looking to perform some relatively straightforward performance upgrades as not much has changed since he bought it in 1981. Has 86k original miles.

After some research, here are a few items I'm considering so I was hoping to get the community's feedback/input on if I'm headed in the right direction.

1) upgrade to a cold air intake?
2) replace exhaust manifolds with larger ones?
3) replace exhaust pipes?
4) upgrade the carburetor?

Open to any other suggestions...Thanks

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Battlac40

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Taking a quick look: 1. Battery hold-down will save you thousands $$$$$ 2. Good strong cam and valve springs. 3. A good detail. 4. Welcome, enjoy.
 

RecklessWOT

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The factory intake is essentially a "cold air intake". That long snorkel tube that goes from the air cleaner to the front of the truck helps it avoid sucking in hot air right on top of the engine and draws nice cool air through the hose in front of the truck (it also has a valve/tube that sucks warm air from around the exhaust manifold when the engine is very cold so it will run better after startup in the winter, then closes off to suck cold air once the engine is warmed up. Carbs don't like cold weather). Even if you had some big shiny intake pipe and a cone filter down under the bumper like they do on tuner cars, you would not gain any noticeable performance. Headers and a free flowing exhaust will make your biggest difference off the bat without changing anything else.
 

Dutch Rutter

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A full tune up can do wonders. New plugs, wires, filters then normal maintenance things like check the timing, dizzy, coil. That will at least give you a solid baseline to build off of.
 

Jeff Heller

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A full tune up can do wonders. New plugs, wires, filters then normal maintenance things like check the timing, dizzy, coil. That will at least give you a solid baseline to build off of.


Dizzy?
I assume ignition coil?
I'm a total noob! Learning as I go, so appreciate the support.
 

Catbox

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Dizzy = Distributor.
It should get a full tune up with a new cap, rotor, and wires.

Headers for your truck will help it breath as will a matching exhaust of your choice.

As long as the carb you have is working well, you should be fine there.

Start simple and learn along the way.
Fix things as you go.
Makes the journey fun.
 

mcarlo86

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I agree with previous posts. Start with the basics, cap, rotor, plugs, wires, fuel filter, etc. What transmission do you have? What is the rear end gear ratio? That is a nice survivor! The battery hold down is missing, so I think he was referencing you should get one so your battery doesn't accidentally slide off the tray.
 

75gmck25

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If you want a quick and simple wake up, then adjust your ignition timing. Factory setting is about 4 degrees BTDC, but you can usually go as high as 12-16 degrees without major issues. Then buy or borrow a dial back timing light and check the timing curve. You want another 18-20 degrees of timing from mechanical, preferably by about 2500 RPM. Do not exceed 36 degrees total.

Make all these checks with the vacuum advance line disconnected and plugged. Then reconnect the line and verify you get 18-20 degrees from vacuum advance. This is for cruise economy, not performance.

Also gap and replace spark plugs, and replace the distributor cap and rotor. if the plug wires look at all bad, replace spark plug wires.

Check your throttle linkage to make sure stepping the accelerator pedal down actually moves the throttle all the way to the limit. If you have a TH350 automatic, also verify adjustment of the kick down cable, which will ensure you get 2nd gear kick down when you floor the accelerator to pass a car.

Bruce
 

82sbshortbed

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An intake and hedders are easy bolt on upgrades that you'll be able to tell a good bit of difference in performance and are realitivly cheap. She'll breath much better after that.
 

Jeff Heller

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Thank you all so far for the input. Although you’re giving me more credit for my mechanical abilities than I deserve...
But it is certainly giving me stuff to research and learn about, which is the rewarding part of this process.
I welcome all the advice!
 

WFO

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An intake and hedders are easy bolt on upgrades that you'll be able to tell a good bit of difference in performance and are realitivly cheap. She'll breath much better after that.
Yeah, that and tune the carb to match that new found breath.

And the bonus is a pile of hoses and other crap that will end up in the trash can.
 

Craig 85

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I've never had a Square Body with a 305 so I don't know if your truck has a 4 BBL carb or not. If it does and you're going to keep the OEM cold air intake set up, maybe step up to the larger air cleaner. The base is bigger than yours and is 2" taller than the standard lid for most GM vehicles.

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82sbshortbed

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Thank you all so far for the input. Although you’re giving me more credit for my mechanical abilities than I deserve...
But it is certainly giving me stuff to research and learn about, which is the rewarding part of this process.
I welcome all the advice!

We can get you through it. Just let us know what you need. Oh welcome to the site from Texas.
 

roo_ster

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Lots of good ideas for the OP.

Reliability & power? First things first: get what you got in good running order.

I suggest all the tuneup/general maintenance before paying money for performance parts. This will get you into your truck and force you to become familiar with it. Buy good quality bits, not the cheapest/cheesiest. It can make a difference.
- Plugs, wires, distributor, rotor, rotor cap
- Fuel & air filters
- Vacuum hoses if not replaced recently
- Coolant hoses & new coolant if hoses or coolant look aged
- Crank case oil change & filter, auto trans fluid/manual gearbox oil, rear end
- Grease all the fittings
- Bleed brakes / replace fluid
- Check brakes while your at it: pads/shoes, rotors
- PS fluid
- Replace accessory belts
- Adjust carb & timing, maybe pull it and clean it up. Maybe rebuild.
- Emissions doo-dads: EGR, etc. Make sure operating & not plugged if not deleted

Somebody mentioned the fuel line near the tank. That is a gem I never tucked into. Will keep that in mind.

Some of the guys I worked for had some real heaps as work trucks. Best bang/buck performance wise was to be had with these gen maint issues. Of those, plugs, wires, dist, rotor generally had a near-instant response.


Looking to get into a squarebody again. I have some experience from back when I did labor and other jobs requiring work trucks, many of which were C/K.
 

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