While the exact procedure for breaking-in a new or freshly rebuilt engine may differ from one engine builder to the next, one thing is for sure; nothing sucks more than getting a fresh build between the frame rails only to run into an issue that requires pulling the engine right back out.
Luckily, that is why engine test stands were created. By allowing an engine to be run outside of a vehicle, potential issues can be identified and easily addressed before the engine is reinstalled into a confining engine bay. The ability to test an engine outside of a vehicle is a serious advantage for everyone from professional engine builders to the home hobbyist.
Unfortunately for the home hobbyist, buying or even building a test stand can appear to be an expensive, daunting task. Also on the mind of professionals and home hobbyists alike, is the issue of space. Storing a relatively bulky piece of equipment that isn’t used every day can pose some challenges regardless of shop size.
Thankfully, PRW has addressed all of the above concerns with their line of Engine Test Stands. Easy to assemble and use, the PRW stands will fit a variety of engine types, and solve the space issue by breaking down when not in use. By offering a modular and affordable test stand, they are bringing down a lot of the barriers to entry faced by the average builder and professional alike.
Building A Base
Part of the ingenuity of the PRW Engine Test Stand is the unit’s modularity. It’s available for purchase as various models ranging from a bare bones “Base Unit” all the way up through a fully outfitted test stand that comes with trick bells and whistles right out of the box.
All of the units are made from a robust 1045-alloy steel square-tube, which offers strength and durability, with a maximum payload of 1,200-1,500 pounds. “That is more of a caster limitation than a limitation of the frame though,” says PRW’s Shaun Snow. “It was designed from the beginning to be collapsible. The idea was to allow people the flexibility to easily store it out of the way when not in use.”
When collapsed, the test stand comes in at about the footprint of a few folding tables, stacked, measuring only 40 inches long by 32 inches wide, and 20 inches tall, for those who are in space-limited shops or home garages. “I have been to several small engine builders shops and floor real estate is always at a premium,” Snow says. That holds doubly true for the home hobbyist who might be working out of a garage spot which is normally reserved for the daily driver.
Four locking casters allow the assembled test stand to be easily moved about the shop even with a fully dressed engine mounted, and each model comes with a pre-fabricated aluminum battery tray and instrument panel. In the base version, the instrument panel is still anodized and laser-engraved, but is left undrilled for your own choice of gauge sizes and layout.
The rear and front engine mounts are adjustable to fit a wide variety of engine families and configurations, with both fixed and adjustable front engine mount uprights available. “The stand was designed to be universal, so while traditional V8 engines will be the most straightforward to mount, we have seen a wide variety of engines from the Cummins diesel to V10s,” Snow explains. “The mounting pads are pretty universal.”
Out of the Box Accessories
For those who prefer an all-in-one, ready-to-go solution, PRW has you covered, with an “accessorized” unit which includes all of the ancillary parts needed for the stand to operate. While previously, collecting and assembling all these parts could be one of the daunting components of getting a test stand up and running, with the accessorized option from PRW, it’s as simple as using a box cutter and reading directions.
Probably the most noticeable upgrade of the accessorized stand is the included radiator and 14-inch electric cooling fan. Designed to have plenty of cooling capacity to keep engines at operating temps when running on the stand, the high-efficiency, curved-blade fan moves significant amounts of air through the stationary radiator.
Also included, as of the past year, is PRW’s fabricated aluminum overflow tank. A 3-inch diameter, 8-inch long cylinder with fittings to plumb into the radiator and mount on the stand, the overflow tank helps prevent boiling over and keeps air out of the cooling system, keeping it as efficient as possible. The overflow tank was previously an optional upgrade, but now comes standard.
Also simplifying the task of putting together the stand are the included switches, gauges, a pre-drilled instrument panel. The gauges consist of a 0-8,000 rpm, 3-3/8-inch tachometer, a 2-5/8 inch full-sweep 140-to-280-degree mechanical water temperature gauge, and a 2-5/8-inch mechanical 0-100 psi mechanical oil pressure gauge. The switches consist of a single aircraft style covered master power switch, two additional on-off toggle switches, and a heavy-duty momentary push-button starter switch.
Also included in the accessorized package is a fabricated aluminum fuel cell. With a 2.5-gallon capacity locking cap, and mounting flange, the fuel cell is built specifically for the PRW engine test stand. It comes with feed and return bungs pre-welded for easy connection to the engine’s fuel system.
Even More Customization
With the optional rotating short-block adapter kit, it allows the run stand to function as an engine stand, allowing an engine builder to build the short-block right on the engine stand, and then swap over to the standard mounts to attach the flywheel or flexplate. Also if attaching the flywheel isn’t critical, you wouldn’t even have to swap to the standard rear mounts. “The short-block adapter could be used to run the engine as long as you don’t need to run the engine with any flywheel or flexplate,” explains Snow.
Whether you opt for the blank canvas or the pre-accessorized version, there is plenty of room for you to put your own personal touches on the stand. “The frame has plenty of space for people to customize it in any way they would like,” Snow says. “People should feel free to drill and mount whatever they like to the stand. The stand was envisioned as being a blank canvas that the end user could custom tailor to their exact needs.”
For someone who may have both EFI and carbureted engines coming through, mounting both a low-pressure and high-pressure electric fuel pump, along with the associated pressure regulators on the frame and controlling them through a switch on the instrument panel could be an easy solution.
With plenty of room on even the pre-drilled instrument panel, you could even add a wideband oxygen sensor to make baseline AFR changes before the engine goes into a chassis. Really the combinations and potential modifications are limited only by your imagination.
With the PRW Engine Test Stand, you can have a mostly blank canvas for a DIY run stand project, with a majority of the heavy lifting already done for you, or complete workstation ready to go out of the box. Either way, you get a useful tool that is also conscious of taking up space when not in use.
Holley Gets Us Up And Running
Once you get the test stand assembled, there are still a few things you’re going to need, aside from the engine itself, that is. For our project, we turned to our friends at Holley to outfit our stand and test engine with the remaining needed parts.
Fuel Pump – P/N: 12-802-1: Holley Blue 110 GPH electric fuel pump with regulator
The famous Holley Blue electric fuel pump will provide plenty of fuel for anything with a carburetor that we put on the test stand, while only drawing 3 amps. With it’s long service life, we shouldn’t ever have to worry about needing to replace it. Plus, it comes with a regulator capable of 4.5-14 psi with a single inlet and dual outlets.
Fuel Feed Line – P/N: 34-150: Holley Chrome 4150 Fuel Feed Line
The pre-bent feed line fits the 4150’s 9.313-inch center-to-center fuel inlet distance perfectly, and comes with the required 5/8-18 inverted flare fittings to bolt right up to our carb.
Carburetor – P/N: 0-82851SA: 850 CFM Aluminum Street HP Carb
This carburetor has features from Holley’s race-series 4150 carbs, but in a milder street version. With mechanical secondaries, screw-in air bleeds, four-corner idle air control, dual accelerator pumps, and dual fuel inlets, it has all the features you want on a performance carb.
Throttle Bracket – P/N: 717-8 Marine Throttle Bracket
A simple, adjustable throttle linkage bracket that bolts directly to the carb mounting stud.
Headers – P/N: 2455-1HKR: Hooker Ceramic Coated Competition Long Tube Headers
Made from ceramic-coated 16-gauge steel with 2.0-inch mandrel-bent primaries and a 5/16-inch header flange, these tuned-length primary tubes are ideal for street engines, are a perfect fit for our big-block Chevy test engine.