THE ROAD TO 400MPH
INSIDE COOK MOTOR RACING’S 2019 BONNEVILLE CAMPAIGN
Bonneville is a place that Reg Cook swore that he’d never return to after his first record in COOKIE back in 2011, because of the extreme hot and dry conditions drivers and crew are forced to endure over Bonneville Speed Week. However, it’s now become an obsession, and one that Cook Motor Racing (CMR) is working hard at year in, year out to achieve the team’s ultimate goal of running over 500mph (373kW) — faster than any human ever has in a piston engine, wheel-driven streamliner. But, unlike other teams that spend years perfecting one combination to an ultimate goal, Reg and his crew are playing catch-up, running on borrowed time and a small budget in comparison to the competition. That has meant that, each year, they spend the off-season developing a completely new combination, everything from naturally aspirated (NA) SR20s to turbo diesels, Honda K20s, Synergy V8s, and Judd Formula 1 engines. All in an attempt to nab as many records as possible and gain the knowledge and experience to achieve his ultimate goal in hopefully 2022.
We’ve covered their exploits extensively over the years, but this time we will be going even deeper, following the team as it gives us an inside look at building a 1000-plus brake horsepower (746kW) SR20 turbo, which is the engine that Reg Cook hopes will propel the CMR streamliner ‘Wairua’ to the two-litre blown gas record — currently held by Ricky Yacoucci at 352mph (566kph). It’s considered one of the hardest records to crack, so what better way to achieve the necessary turbo knowledge needed for the 500mph programme than to chase 400mph (644kph) with a motor that CMR has campaigned since 1991?
Sure, you might think a 1000hp turbo SR isn’t all that hard to achieve in this day and age, but, being a pump-gas record that the team is chasing, this means that it will run on regular petrol, something that no other four-digit-producing SR has done before. To further complicate the situation, the engine needs to survive not just for a few seconds at full throttle but for almost two minutes on full power, and then go into impound and repeat the feat the following day. Should Reg achieve this, he will not only beat the existing record by 50mph (80kph), but, by cracking 400mph, he will also earn a black cap — which is held by only eight teams worldwide.
So, how do they intend to achieve the seemingly impossible? As Reg puts it, like all their wild ideas, it will begin with brainstorming at the CMR lunchroom table — the location of many fierce debates — and then involve the input of some very talented minds from around the world.
“We can sit here and pretend we know everything, or we can talk to other people and get a better understanding of what might work. Guys like Mark Mazurowski at Mazworx; Murray Coote at MCA Suspension; Darren Palumbo at Billet Blocks; Peter McDonald, who does a lot of billet blocks for RBs; Brad Shields in Tasmania; Dewhite Scott; or Phil Morrison. Every single one of those people has a different idea of how to make it work. No one has a mortgage on the truth about building the SR20, so if we were to just follow any single one of them, I think we’d have trouble, as none of them have ever done what we’re trying to. In the end, it’s about listening to everybody and their past experiences and brainstorming. When I come up with what we think is the recipe, we will then table it and let them attack it. And if the idea stands after that, I will run with it, but the continual process of brain storming will be essential.” says Reg.
“At the moment, we are going single-turbo, but we don’t think it will work. We just don’t have the answer right now”
What is known is that the Nissan SR20DET will utilize a billet block and one of CMR’s heads employing the same custom roller-rocker set-up used in the 2011 record-setting NA SR. That allows for much larger lift cams than a modified VET rocker and will achieve similar flow to that of the K20 Honda heads. But every other component is still up for debate.
“The closest to what we want to do is what Murray Coote runs in his World Time Attack S13, although his is 900hp [671kW], 2.2-litres, and on E85. We’re two-litre and on pump gas. E85 is a lovely fuel — its combustion is colder, it makes more power, and it’s not as hard on exhaust seats. If we copy his engine, we will be in trouble,” says Reg. But that’s not to say that lessons can’t be learned from it.
Once the build recipe is sorted, a mule engine using a factory block and crank will be built up and run on Reg’s in-house engine dyno at full power for up to two minutes, to test the theorized combination and see what the effects are internally — what pistonto-bore clearance is needed? What size gudgeon pin will survive? What will happen when the cylinder temperature hits almost double the level that it’s designed for? These are all questions that CMR is endeavouring to answer within the next month, so that the two billet blocks headed to the salt won’t be likely to end up alongside the parts shown on these pages — all offerings to the god of speed, as Burt Munro would say.
But building the engine itself is really only half the challenge facing the team. There is also the issue with getting the car up to speed, as Reg elaborates: “The problem we have is that we’ll push-start the car, and the engine needs to get to 5500rpm before the boost will kick in. Up until that point, we have only about 90hp [67kW]. Is that enough to make the car accelerate, as it weighs 2800 pounds [1270kg]? Our first gear is 120mph [193kph]. People start talking about compound turbos, rather than just one larger turbo, but who do you talk to? Hardly anyone has done it successfully without spending six to nine months on the dyno figuring out the combination. And even then it’s not been designed to last the duration that is required. At the moment, we are going single-turbo, but we don’t think it will work. We just don’t have the answer right now.”
So, assuming the team can build the engine capable of making the required power for two minutes, then work out a way of it getting off the line and up to speed, the tuning and data logging will then be vital, as making it through one 400mph run is only half the challenge: to set a record you must make the return pass the following day, and the car gets impounded between those two runs. Knowing and controlling what’s going on inside the engine to keep it in one piece is vital, explains Reg.
“We could possibly break what is the hardest record to break, but we need to be able to back it up. It’s no good if we kill an engine. Probably 90 per cent of the cars that ran over 300mph [483kph] last year had hurt their engines and weren’t able to complete the backup runs. We don’t want to be in the same boat.”
To achieve this, pressure sensors reading each combustion chamber will give them a first-hand look at the flame pressure front, and exactly when situations such as detonation will occur. Getting those extremely expensive sensors into the chamber is another challenge the team is currently working through.
Check back next month, by which time the courier will have been running red-hot to Reg’s barn, and we will see first-hand the components that the crew has decided to go with.
“What will happen when the cylinder temperature hits almost double the level that it’s designed for?”