How to Swap in a Carb-Equipped LS Engine

Carb-Equipped LS Swap 101 - Want modern LS power but without the hassles of retrofitting fuel injection? We show you how.

Patrick Hill Jan 28, 2014 0 Comment(s)
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1987 Caprice LS Swap Power Steering 2/39

24. Turning to the power steering system, we installed this 135-degree hose first, which connects the fluid reservoir to the pump. Don’t try to install it on the reservoir first. You’ll never be able to secure the clamp on the pump end of the hose.

1987 Caprice LS Swap Power Steering 3/39

25. And the reservoir slips onto its bracket. From there, we connected the return line from the steering box to the reservoir. We reused the factory 305 high-pressure power steering line from the pump to the box, but had to change the shape of its hard line a bit for fitment. The return line was just a simple matter of reusing the factory hard line end and clamping on a new piece of hose.

1987 Caprice LS Swap Modify 4/39

26. To make things easy, we converted to an electric fan. But on an ’87 Caprice, the factory fan shroud also functions to hold the radiator in place. To clear our new fan unit, but still secure the radiator, we modified the top and bottom portions of the factory shroud as you see pictured.

1987 Caprice LS Swap Secure 5/39
1987 Caprice LS Swap Lower Radiator 6/39

27. For our lower radiator hose, we reused the factory 305 hose, and only needed to trim it back some to fit the 5.3’s return outlet. Once we had the trim and fitment just right on the old hose, we went and got a new one, cut it to match, then clamped it on.

1987 Caprice LS Swap Steam 7/39

28. Another coolant fitting we had to add was this line from the factory steam tube from the heads to the radiator. We installed a nipple fitting here, then ran a piece of high temp hose from it to the outlet on the steam tube.

1987 Caprice LS Swap Holley Belt 8/39

29. The Holley accessory drive kit comes with a belt tensioner that installs on the passenger side to keep the new serpentine belt nice and tight.

1987 Caprice LS Swap Serpentine 9/39

30. The Holley accessory drive uses a Gates K060944 serpentine belt. If your parts store doesn’t carry the Gates brand, they can use a cross reference guide to find the equivalent in the brand they carry.

1987 Caprice LS Swap Holley 670cfm 10/39

31. For fuel delivery we went with this Holley 670 CFM Ultra Street Avenger vacuum secondary carb. It has a lightweight aluminum main body, with billet metering blocks and base plates.

1987 Caprice LS Swap Mount 11/39

32. We mounted the relays for the ignition system here on the passenger side front fender.

1987 Caprice LS Swap Holley Fuel 12/39

33. To feed our carb, we installed a Holley electric Blue pump back by the gas tank. We just cut the factory feed line, spliced in our pump, then secured it to this crossmember.

1987 Caprice LS Swap 13/39

34. To hook the alternator into the car’s electrical system, Holley includes a new alternator plug with its accessory drive kit. It’s a four-wire plug, but in our application we only needed one. With the unnecessary wires cut away, we spliced our remaining wire into the factory wiring harness per the instructions.

1987 Caprice LS Swap Electric 14/39

35. To keep the 5.3 cool, we hit the local boneyard and snagged the dual cooling fan assembly from a ’97 V-6 Camaro. After a little modifying, it fit like a glove. Then we wired into the factory harness using a factory coolant sensor, with a turn on temp of 180 degrees.

1987 Caprice 5 3L LS Swap 15/39

36. And here’s the finished installation. It runs and drives perfectly. The only thing left to do is visit a qualified A/C shop and have them make up some new hoses for the compressor, then charge the system.


Hooker Headers
Aberdeen, MS 39730
Seffner, FL 33584
Holley Performance Products
Bowling Green, KY 42101
Torrance, CA 90503
MSD Ignition


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