If you’ve been following along with a few of our past Engine of the Week features, you’ve likely noticed we spent some time at Noonan Race Engineering in Spartanburg, SC this year. We featured a couple of their infamous Hemi engines – the 4.8 and 4.9 bore space engines – as well as a shop tour of the state-of-the-art facility. The shop was even crowned our 2023 America’s Best Race Engine Shop earlier in December. With all that we know about Noonan, one thing we weren’t aware of, until our visit, was that the engine and machine shop was working on an all-billet V-twin engine. Naturally, once we knew about it, we had to find out all the details!
Noonan’s Barry Pettit shared all he could about the new billet V-twin engine platform. He told us it began as more of a “look what we can do” type of engine project, but the shop has had some serious interest in the engine, and for good reason – it’s awesome, makes gobs of horsepower and is based on Noonan’s 4.9 Hemi!
“It’s a pretty unique piece for us,” Pettit says. “Essentially, it’s a two-cylinder version of our 4.9 Hemi. The idea was to try and shrink it up initially for prototype reasons and that is actually what this engine is getting assembled for.”
Shop owners Jamie and Renee Noonan are working on a few cylinder head ideas that they want to try with the V-twin platform. However, the billet V-twin has the same front drive system as the 4.9 Hemi, as well as a normal Hemi bell housing on the back and even the same rocker geometry.
“As far as R&D, it’s very effective on cost and time for us to be able to slap something on there and see if it makes a difference,” Pettit points out. “We’re pretty excited about it. It tends to get a lot of attention. A lot of guys are trying to fit them in Harleys, and we have to show it to them because it’s pretty big.”
While a regular Harley motorcycle isn’t the typical customer for this billet V-twin, the engine was developed for motorcycle drag racing applications. This prototype version will be ProCharged to make some extra boost and high horsepower, which Noonan has become excellent at delivering. That also means it has all the quality components.
“This is going to be treated almost exactly like a V8 Hemi,” he says. “We have a billet crankshaft, billet connecting rods, a Manton rocker system, exactly like what we’re going to run in a Pro Mod. The intake manifold is meant for pretty insane amounts of boost pressure because we’re going to end up hanging a ProCharger off the front of this one. The size is not really determined yet, but again, this would be essentially the exact same thing you could bolt up to a normal V8 Hemi.
“It’s a 4.150″ stroke, 4.565″ bore size with a 70mm custom camshaft that we’ve had made by Militia Racing. It’s a pretty sizable cam, especially when we’re talking about a V-twin. It’s about as big as it is long. The engine really has all the aspects – that way we can get true test results.”
While much of the billet V-twin engine resembles the 4.9 bore space Noonan Hemi, one component that differs is the oil pan for the dry sump oiling system.
“We’ve done some billet pans for LS engines and other stuff like that, but this is going to be a dry sump oiling system,” Pettit says. “This pan is another unique piece that we make in-house. It has o-ring seals, clearance for the main cap studs – it’s a pretty wicked piece. Just part of the ability that we have when we work with billet. We can do solutions like this. Even for a test piece, you can see the amount of engineering we had to go into just for an oil pan. The engineering and programming teams always amaze us.”
This billet ProCharged V-twin engine has an estimated horsepower level somewhere between 900-1,000 horsepower, which is crazy to think about coming out of just two-cylinders. While just about any V-twin fan would want to have this on their motorcycle, the true intent of the engine was for Nitro V-twin applications. That said, Noonan Race Engineering is still figuring out where the best fit for an engine like this really is.
“It was really kind of a ‘look what we could do’ piece that also helped aid our R&D,” Pettit says. “The first one we made, we had a customer who was just dead insistent on he had to have it, which is great and it’s running well for him. We’ve done another one up here to put on the engine dyno and get some R&D work done. The idea is, and most of the people who call, are trying to run nitro in a motorcycle.”
No matter what this billet V-twin engine gets put into, it’s sure to make that vehicle a rocket ship being based on the 4.9 bore space Hemi. It’s also sure to be a conversation starter.
Engine of the Week is sponsored by PennGrade1, Elring – Das Original and NPW Companies. If you have an engine you’d like to highlight in this series, please email Engine Builder Editor Greg Jones at [email protected].