I'm only just now learning about the Grenadier. I had a few random thoughts about this vehicle.
I am very interested in the fuel economy of the Grenadier. As the owner of 2 BMW's (X3 M40i and an older BMW 340i) with the B58 engine, albeit in a higher level of tune, I've gotten outstanding US MPG results (low to mid-30's) on long trips. IMO, the B58 engine is an excellent combination of power and efficiency. However, the EPA ratings of the Grenadier is somewhat confusing. It's listed as 15 MPG city, 15 MPG combined, 15 MPG highway. Considering the EPA testing procedures for city and highway, it doesn't seem possible that the two numbers would be identical, at least not for the B58 engine.
With the B58 engine, I cannot see how the Grenadier can't exceed its 15 MPG highway rating, even with its less-than-ideal aerodynamics. In the past, I've owned a Jeep Wrangler and a Toyota 4Runner, both with thirsty 4.0L 6-cylinder engines. I easily exceeded 15 MPG on both vehicles which were both lifted and fitted with off-road tires. The Grenadier's aerodynamics can't be any worse than my old Wrangler. I have to think the Grenadier will very likely pummel the published MPG ratings. I have to believe that 20 MPG highway should be easily attainable, if not higher.
I looked through all the brochures. I didn't see anything regarding an auxiliary fuel tank option. A 23.7-gallon (US) gas tank is adequate, but on the trail or overland, it could prove to be a bit small, especially at the rated 15 MPG. Has Ineos provided any information about adding additional fuel capacity? Me personally, I don't like carrying auxilary jerry cans. When not in use, they add to the clutter around my house.
I'm also very interested in how the B58 was detuned to 282 HP. If it contains the newest B58TU engine (B58B30M2), the BMW's current lowest output version of that motor puts out 382 HP, 369 FT-LBs torque (US). I have to wonder how the Ineos and BMW engineers detuned the engine down to 281 HP and 330 FT-LB. For the price of the Grenadier, it doesn't seem possible that the engine internal design and components would be modified to provide less motor performance as that would be cost prohibitive. I'm not even so sure a smaller turbo fitted to the B58TU engine makes any sense. It seems to me that the easiest and cheapest way to drop the normal performance figures of the B58TU engine would be to simply remap the ECU for less turbo boost, hence the lower power numbers. There's also the question of intake plumbing which I'm sure is greatly reduced, especially for the snorkel equipped models, along with changes in the size, location, and number of the various coolers and heat exchangers.
That being the case, I wonder how difficult it would be to get back the missing 101 HP and 39 FT-LBs of torque. A B58 engine can be easily tuned to make well over 500 HP for a very nominal amount of money. I've seen a growing number of Jeep 392 Rubicon Hemi Wranglers and Ford Bronco Raptors on the trails over the past year. A 500+ HP Grenadier might be an interesting project. Certainly the motor is capable. The ZF 8HP51 box might need to be upgraded to a 8HP70. The differentials and axles should be fine, but I'll need to do a bit of digging to understand the componentry involved.
I'm certainly interested in seeing the Grenadier in person and up-close.
