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Introducing the Radial Dynamics RDT Steering Pump!

RadialDynamics

Yellow Skull
Joined
Dec 22, 2020
Member Number
3165
Messages
155
Loc
Greenfield, MA USA
Ladies and Gentlemen, it is my honor to introduce the Radial Dynamics RDT steering pump.

With a full race season of testing complete and the 2022 Ultra4 4400 National Championship to its credit, this is the next generation in Trophy Truck (TT) pump technology. The RDT is a significantly advanced design, fully engineered in-house to deliver improved performance, reliability, and serviceability in a smaller, lighter package compared to any existing TT pump on the market.

Starting with the basics, the RDT features a massive 20cc/rev displacement and flow control cartridge valve that regulates max pump output to 9 GPM. While this pump does require an external pressure relief valve, it can handle relief pressure settings up to 2000 PSI.

The inlet is a -16 size and the -8 outlet port is a side exit from the 6061 billet aluminum body that can be swapped to either side of the pump for easier plumbing. The ¾” keyed shaft features large ball bearing support and the internal port plates are manufactured from a special aerospace grade bronze that provides the ultimate wear and cavitation erosion resistance.

The overall size of the RDT is notably reduced from that of a TT pump, weighing in at an astonishing 7 lbs compared to 11+ lbs for a cast iron TT and 8.5 lbs for the next lightest aluminum TT pump.

Pricing and Availability: Retail price for the RDT is $2000. The final components are being queued for manufacturing as we speak and the first batch of 40 pumps is estimated to be ready to ship by the end of February.

Pre-orders will be available on Wednesday to reserve pumps in this first batch and to be clear, pre-ordering is NOT used to fund R&D. The R&D phase is complete, fits/tolerances established, materials finalized, and the design has been proven this year in the most punishing Ultra4 and rock crawling conditions possible.

There is so much more to tell than can fit in one post so I will be sharing more details throughout the week. Photos are of prototype RDT pumps and renderings are the production design, for which the only changes are a revised front mounting bolt pattern and billet rear cover.

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Great to see your innovation come to the market! Who all did you have test the product? Price point is definitely for competition use, but that is where something like this is needed. Would like to know more about what you do for the internals to improve the product.:beer:
 
Great to see your innovation come to the market! Who all did you have test the product? Price point is definitely for competition use, but that is where something like this is needed. Would like to know more about what you do for the internals to improve the product.:beer:
Thanks! Beginning with pre-running the week before KOH 2022, prototypes were tested in 4400 by Josh and Rusty Blyler (one each) and Sean Haluch in 4800. I also have another prototype on the Fun-Haver front and rear steer Red Dot crawler. More details about testing will be shared this week but to make a long story short, Josh and Rusty took 1st and 5th overall, respectively, in the 4400 national points championship running these prototypes all season long.

This isn't just another TT pump, it is an all new design loosely based on a completely different (and 30 years more modern) platform than the outdated Saginaw pumps on which the TT pumps are based, including all of the newer aluminum TT pumps. The internal structure of the RDT has some fundamental differences that make it inherently more reliable and safer than anything else currently available. More to come!
 
While the new Radial Dynamics RDT steering pump features the same large displacement as a TT pump to deliver the same impressive high flow capabilities, the RDT is not just another TT pump with the same old components wrapped in a new body. The RDT design is derived from an entirely different (and 30 years more modern) OEM platform with fundamental differences that make it inherently more reliable and safer than any other large displacement pump.

Anyone that has been around TT pumps long enough has likely at some point experienced seal problems with the rear cover. Let’s cut one in half to find out why.

The bottom cross section of an actual TT pump shows how low-pressure oil from the reservoir floods the front half of the pump body and the cam pack (the section of the pump doing the actual pumping) pushes high pressure oil into the rear cavity. The single o-ring that seals the rear cover of the TT pump body against high pressure has a significant amount of stress to deal with and in the event of a seal failure, the resulting oil leak allows oil to spray out of the back of the pump.

The RDT is designed opposite, with low pressure oil flooding the rear half of the pump body and therefore, the rear cover o-ring needs to seal only against whatever pressure is in the reservoir which should typically be 10 PSI or less. The RDT cam pack pushes high pressure oil into the forward cavity of the pump body where it is contained by o-rings with high pressure PTFE backup rings to prevent o-ring extrusion. In the very unlikely event of a high-pressure seal failure, oil is still contained completely within the body of the pump.

Not only does this design improve sealing reliability, but it also reduces stress in the pump body. Consider that the entire rear cover of the TT pump is exposed to high pressure and therefore acts as a “piston” trying to split the body apart with 9,850 lbs of force at 1600 PSI. By comparison, the annular high-pressure cavity in the RDT pump means that the body sees only 6,000 lbs of stress acting on the rear cover at the same pressure.

RDT TT Comparison.jpg
 
Pre-orders for the RDT steering pump are available now on the Radial Dynamics store at: RDT High Flow Steering Pump (PRE-ORDER)

While you reserve yours, let’s gather round for story time. The RDT has been a long time in development and the first prototypes came together last winter, just in time for King of the Hammers 2022. Josh and Rusty Blyler of Big B Motorsports graciously agreed to be my test pilots, promising to put this new design through the paces. The great thing about Big B is they don’t mess around. They show up an extra week early to the lakebed with FOUR nearly identical cars, two for prerunning and two for racing.

The plan was simple, install one RDT prototype on Josh’s prerunner and if successful, put a second on Rusty’s. After the first day of testing, performance was feeling great, so the second pump got installed. Josh and Rusty spent that week driving 500 miles each of KOH course at race pace to test the limits of their equipment in a non-critical environment.

The pump results were fantastic and that was supposed to be the end of KOH testing for the prototypes. Originally, they planned to run their existing cast iron TT pumps in their race cars for the 4400 race, only because they had a spare on each car and a pile of spare pumps for inventory at every pit. Of the RDT prototypes, we had only the two.

However, once Josh and Rusty climbed back into their race cars with their cast iron pumps, they immediately felt they had been spoiled by the steering experienced in their pre-runners the preceding week. The decision was made… they would run the main race on the prototypes knowing that if there was a failure, it would take additional time to replace hoses and mounting brackets in addition to the pumps. I freshened up both prototypes on the lakebed and off they went.

On race day, Rusty was holding physical 3rd place until a suspension joint failure ended his race late in the third and final lap. Josh had spent the day following close behind, taking 3rd place overall. This is KOH, the toughest one-day off-road race in the world and watching Josh cross the line with a podium result on the very first trial of the new prototype pump was without a doubt a highlight of the year!

 
Awesome, so will there be a trail version for those that don't need a race version?

and again very cool on getting the product out! Still requires a cooler, filter similar to a standard pump?
 
Awesome, so will there be a trail version for those that don't need a race version?

and again very cool on getting the product out! Still requires a cooler, filter similar to a standard pump?
Thanks! Unfortunately there will not be a "trail version" of this particular pump as it is far enough removed from the OEM model on which it's based that it can't be built with mass produced parts. It does still require all of the normal system components including a cooler, filter, and an external pressure relief valve since the only valving integrated into the pump is flow regulation, not pressure relief.
 
better start saving then! I was thinking of looking at a cast housing but I suppose that wouldn't save that much given the numbers needed to make costs work out.

From the specs it appear a single pump could handle rear steer as well?
 
Yeah, although the body is the most expensive component of the assembly, there are so many custom components that go into it that even a lower cost cast housing would not make a drastic difference in overall price. It has no problem handling front and rear steer duty though.
 
How large is the new Radial Dynamics RDT steering pump? Its overall dimensions fall between that of a TC/CB-X pump and a traditional Trophy Truck TT pump. The shorter overall length and the side, rather than rear, outlet port allow this pump to be installed in places where TT pumps simply can't fit.

The RDT can be mounted by the front mounting face alone although the production version also features a flat rear cover which allows the rear cover bolts to be utilized for rear support.

In cases where an engine is already setup for an existing TT pump, an optional bolt-on rear mounting adapter for the RDT pump provides the same front-to-rear mounting face dimensions and rear bolt pattern as a TT pump, thereby requiring only a new front mounting plate to facilitate the interchange of an RDT in place of a TT pump.

The RDT has been engineered to deliver TT pump displacement in a smaller, lighter, but also heavier duty and more reliable package compared to anything else on the market.

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More tech that sets the new Radial Dynamics RDT steering pump apart from the rest!

Of all the components within a steering pump, the cam ring is without a doubt the most critical piece of the puzzle. This ring features an elliptical profile, inside of which a set of rotating, sliding vanes maintain contact with the ellipse to create a repeatedly growing and shrinking cavity volume.
The dimensions of the cam profile and the thickness of the ring are what determines a pump's displacement, or how much oil it moves per revolution. The Radial Dynamics RDT features the same displacement as a traditional Trophy Truck TT steering pump, but as can be seen, it is a beefier ring with a significantly thicker wall than the TT.

Not only does the RDT cam ring see less stress thanks to having a minimum wall cross section more than double that of a TT pump, it is also made from a more appropriate cam ring material (hardened stainless) than competitor designs (low alloy steel) which offers not just good mechanical strength, but also exhibits ideal resistance to wear and cavitation erosion.

These photos show actual cam rings evaluated after completing the King of the Hammers 4400 class race in the same car, same system setup, one year apart. The RDT ring still has a perfectly smooth cam surface, even showing the original precision ground finish. Meanwhile, the ring out of the TT pump shows burnish marks from lack of lubrication as well as chatter due to cavitation unsettling the vanes and pock marks where cavitation has eroded the cam surface.

Heavier ring, smaller/lighter pump, better performance. Welcome to the RDT.

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