[Stratos]

Some of you might know my fixation with heavy vehicles. As proof, check out my profile picture on the left. I have immense love and respect for commercial vehicles as they are some of the hardest working machines, helping move tons of cargo around, thus making an important contribution to the Indian economy. It has always been a dream to get behind the wheel of a truck. All that was about to change, thanks to a phone call I received one morning from GTO. He asked if I was interested in testing the Tata Prima. In his mind, he very well knew my answer. There was no way I was going to refuse an opportunity of getting behind its wheel.

After the drive, GTO asked me whether I'd rather have driven this truck or an Audi R8. Well, he knew my answer here too . You could say that I'm nuts about commercial vehicles.


I have driven a truck before, albeit just for 5-10 minutes. This was at a totally different level; I was about to drive the truck used in the T1 Prima Truck Racing Championship! My earlier thread on these races: Link.

Truck racing is a popular sport in some countries, whereas in India, 2014 was the first year that it was held. International truck racing has various manufacturers competing against each other. Thus, the differentiating factors are how manufacturers tune the trucks and of course, driver capability. The Prima T1 truck racing series is slightly different though. All the competing trucks have identical specifications, and the only differentiating factor here is the driver. Personally, I would love to see other manufacturers (Mahindra, Bharat Benz, AMW, Ashok Leyland) also come forward & take part in the Indian truck racing scene.

[Stratos]

My earlier interaction with the Prima truck was exactly a year back, when it was first showcased at the Buddh International Circuit (link). The truck for the second season is almost identical. It's the 4038.S tractor fitted with a Cummins ISLe 8.9-liter diesel. The engine is mated to a 9-speed Eaton gearbox. Drivetrain specifications remain similar to the ones sold in the market. However, as per Tata Motors, the engine has been tuned for racing, resulting in an improvement in acceleration & overall performance. The engine produces 370 BHP @ 2100 RPM and max torque of 1550 Nm @ 1300 rpm. The Prima race truck's fuel economy is 1.6 kmpl .



The following changes differentiate the current season's truck from the one that raced last year:

• Rear axle ratio has changed from 4.3 to 5.126.
• The new truck is approximately 350 kg lighter, thanks to lighter leaf springs and a dummy fifth wheel coupling.
• Top speed has increased to 130 km/h (from 110 km/h).
• Ride height has reduced by approximately 55 mm, due to a reduction in the leaf spring stack.
• New air-pressurized brake cooling system.
• Caster angle of the front axle has gone up from 2.4 degrees to 6.5 degrees.
• Rear view mirror added inside the cabin (as per driver feedback from last season).
• Improved seat structure, larger diameter steering wheel, tail lamp repositioning and extra tow hooks at the front.

The headlights have been removed and a metal plate covers their cavity. Fog lights stay in their place as per race rules:


The newly added rear view mirror. Definitely useful to see who is tail-gating you on track


Side under-run protection:


Tail-lights move slightly inside the chassis to prevent damage from racing incidents. Also notice the rear under-run protection bar:


Brake Cooling System: One of the most important components in racing are the brakes. The Prima gets drum brakes on all four wheels, which tend to get really hot. Heat can hamper braking performance during the race. To tackle this, racing trucks have a brake cooling system, wherein water is sprayed on the brakes every time the driver lets go of the pedal (after braking). This system was present in last year's truck as well. In 2015, the mechanism has been further modified. The system will now spray water on the brakes throughout the race, without any gaps. The water tank's capacity is 120 liters. I don't get this concept...why should the system keep pouring water on the drum surface even when the truck is driven flat out on a fast straight?

These two cylinders carry 120 liters of water. The water spray operates pneumatically:


The pipe that carries water to the drum brakes:


Specially built 315/80 R22.5 rubber from JK Tyres. The entire wheel rim is made from a single piece of metal:


My drive took place at the Tata Motors test track in their Pimpri factory. We've visited this track earlier for the Manza, Vista & Nano reviews. The test track is approximately 1.8 kms long, with a turn in the middle. At one end of the track is a small roundabout, whereas the other has a big circle to test the steering & body roll. Surface quality is excellent and all Tata vehicles go through their high speed testing here.

[Stratos]

Releasing the pneumatic handbrake brings out a very industrial whooooosh sound. Insert the key and press the rubber-padded button to start the engine. This sequence brings the truck to life. The Prima will only fire up in neutral gear.

Once settled in the racing seat with a 5-point harness, I was ready to go. I took my time getting used to the truck, especially its sheer width. After confirming with the test driver that we were the only ones on track, I chose the center line. This was done to make sure that I don't scrape the truck by underestimating the distance between it and the guardrail. Literally, it took 10 minutes to get used to the truck and understand how it reacts to driver input. The steering is quick & responsive. Although power-assisted, it is quite heavy to use with one hand. Additionally, the steering transfers smaller vibrations to your body through your hands. It's diameter is perfect, making it easier to perform quick turns without much arm movement.

Race truck has stripped-out interiors:


Ignition key with the engine start button on the left:


Instrument cluster from the standard Prima. Digital speedo & gear indicator too:


This racing truck has no norms to meet (e.g. pollution & sound), thus it gets a much shorter exhaust pipe. The result is a ear-tingling, body-shaking exhaust note which is actually sweet to your ears!! Part of this amazing aural experience is the continuous turbo whistle. Vibrations are bearable up to certain speeds only. Considering the fact that all the interior damping has been taken out, you are left with a naked metal cabin and almost negligible upholstery. The racing seat with its 5-point harness is very comfortable. The window glasses have been taken out, and safety nets have been attached instead.

Racing seat with a 5-point harness:


Let us now move on to something that was terrible - the 9-speed Eaton gearbox. This transmission has 8 forward gears + 1 crawler gear + 1 reverse gear. During my very first run, the test driver told me that I may have issues getting into 5th. Boy, was he right! 5th was the most difficult gear to get into. The gear knob literally needed a thrashing at times to upshift from 4th. Fighting to get into 5th gear - while holding the steering wheel with one hand - wasn't comfortable at all. One of the employees who had driven the truck confirmed that the gearbox was having issues with the gear getting into its gate. This reminded me of the time when Tata showcased the Prima at the Buddh International Circuit. Even then, the gearbox had synchronizing issues. I've driven the Mahindra Navistar and would rate its gearbox to be much better & smoother to use.

The 9-speed Eaton gearbox. L = Crawler gear:


Pull the red knob & move it to engage / disengage the handbrake:


I put it in first and rolled off. The gear ratios are so short that you are in third by the time you reach 15-17 km/h! Thus, your first few moments with the truck are spent in changing gears. After you reach the fourth gear, you'll finally get time to make other observations. This 4038 can pull ~40,500 kg and if you aren't hauling any weight, you can take advantage of the immense 1,550 Nm of torque. Don't want to go through the first few gears? No problem. Put the truck in third gear at standstill itself!! It will still move off effortlessly. Obviously, without any load attached, the truck doesn't feel heavy. It is easy to drive, thanks to the power steering. The steering wheel in this truck has been changed from the stock one to a smaller diameter racing wheel. One of the rules for truck racing is that the steering wheel should be easily removable by the driver - reminded me of Formula 1 .

Steering removed from its column:


Pull the circular red collar to remove the steering. Just push it back onto the column to attach it again:


The cabin setup. Notice the safety nets instead of (window) glass:


The Prima handles like a surprisingly well-behaved vehicle and willingly performs quick directional changes when made to do so. The standard Prima has a leaf-spring suspension setup and also comes with a cabin suspension. In this Prima race truck, the cabin suspension has been locked and the truck sits lower due to a reduction in the number of leaf springs. This modification has considerably reduced body roll. The Prima can manage some tight turns at decent speeds without tipping over. The modification has also made the suspension stiffer, due to which the Prima can lift its rear wheel off the ground during sharp cornering. I tried going round and round the circular section of the track to check its body roll & grip levels. The angle between the horizon and the truck's windshield kept increasing. Still, it didn't scare me as the tilting of the body happens at a slow pace. The only reason I had to stop my 'body roll test' was because the test driver (& my co-passenger) was starting to look worried and had moved from his seat, ending up glued to the passenger door.

Body roll is much lesser than a standard Prima:


Not too difficult to go into 'tripod' mode as seen below:


Our chase vehicle - an open Tata Winger. Top speed = 100 km/h:


Wicked-looking Safari Storme rescue car:

[Stratos]

While driving the Prima, the test driver told me that the max anyone had driven this truck on their track was 138 km/h (indicated). I was about to break that record .

Since the cabin is stripped of all non-essentials, there was no place for me to park my camera. The test driver volunteered to record a video of my drive. To manage a good run on this particular track, it's very important to perform quick & accurate upshifts. One mistake and you either bend forward with the truck (if you mistakenly engage a lower gear) or the truck starts to shudder wildly (if you engage a higher gear). In both cases, your lap is destroyed as the track isn't long enough to allow a recovery. You have to restart from the beginning of the track.

I went smoothly up to fourth gear, at which point, fifth started becoming an obstacle for a fast lap. Still, I managed to slot it in without losing much speed & time. As I progressed all the way to eighth gear, I could see 130+ km/h on the speedometer...and the needle was still climbing. On this run, I ended up touching 136 km/h. The test driver confessed that it took him many more practice runs to attain 136 km/h; I did it after merely 20 minutes in the driver's seat of this awesome truck. The main reason why it's difficult to attain high speed is that, by the time you are touching 135+ km/h, it's time to brake hard as the dead end is visible. The brakes, which lack bite, don't help either. To safely stop in time, you have to stomp the brake pedal and simultaneously, use some serious engine braking. Of course, even during engine braking, the gearbox will give you a tough time in downshifting. When doing so, the rear wheels start bouncing so hard that they create a disturbing 'thud-thud' noise. Reason? No load at the back, and the rear wheels tend to lose grip as all the weight gets transferred to the front (under hard braking). The cabin throws in some of its own "hammer-on-sheet metal" sound effects as well.

We took off again from the start. Slowly gaining enough speed, the gearbox behaved well and I touched 137 km/h quite early, with a good amount of tarmac still left. As the truck crossed 136 km/h on the speedometer, the cabin started shaking vigorously (something the driver warned me about earlier). As I crossed the numbers 139, 140 and 141, the vibration levels increased. I topped out at 142 km/h on this run....with a huge smile on my face! After a quick combination of foot + engine braking, we came to a stop. The test driver stated that I was currently the fastest person with the Prima truck on this track. As someone who has a passion for trucks and buses, it was a proud moment for me.

One of the Tata Motors' engineers involved in this project had studied the truck and its vibrations up to 138 km/h, but wasn't aware of how it behaves after that speed. He wanted my feedback on the last 4 km/h. I truly had the time of my life that day. Have driven some decent cars before (including Merc AMGs), yet nothing can come close to the excitement and adrenaline rush I experienced while driving a racing truck at its mechanical limit.

Below is an amateur video of me clocking an indicated 142 km/h in the Prima:

https://www.youtube.com/watch?v=q5p_EjEm9bY

The only things I did differently on the hot lap were quick gearshifts and late braking. All this was possible thanks to the Prima Race truck, which can be a monster to drive, but is also one of the most forgiving vehicles that I've driven. At no time during the drive did I feel as though I was driving something very wide and too big. The engine is responsive by truck standards and the Prima can take almost anything that you throw at it in its stride.

A couple of days later...

Some days after the drive, my top speed record was beaten by the test-driver himself!! If the drive was a cake, then the cherry on top was the SMS I received from him. It read in Marathi "Me kaal 143 touch kele. Punn, mala dhadhas tumchya mule zhala, bara ka sir! Nahitar me punn ghabrat hoto". Translated, the test driver Pandurang said "I touched 143 km/h. But I only gathered the courage for this speed because of you. Otherwise, I was scared to do it". I was delighted to have received that message. After all, when I first arrived on track, it was Pandurang who made me comfortable in the truck. He was sweet & supportive throughout.

[GTO]

Thread moved from the Assembly Line to the Commercial Vehicles Section. Thanks for sharing!

[Zinda]

Thanks for sharing your experience Stratos! You lived your dream, bettered the record at debut and entertained us with a nice writeup!!

[abhinav.s]

Kudos to a great review Stratos. Very well detailed and happy to see that T-BHP delves into this amount of detail for CV test drives too!! (Not that this is an ordinary CV).

[Aditya]

Nice report Stratos and that was some pretty good driving. You did well to reach that speed despite the rather messy gear change.

As a lover of commercial vehicles myself, I totally understand your excitement. Fast cars are fun, but fast trucks are epic!

5 stars!

[MaheshY1]

Wish we had the Semi's of the west with the roads and legal speed limits to unleash them.
But on any road (let alone a small track) 142 for an indian truck is magical. 'Too good to be true' kinda thing.

Thanks GTO for calling Stratos. Keep calling him now and then so we get the idea of what it's like to be behind the wheel of a monstrous machine from a fellow BHPian.

[DHABHAR.BEHRAM]

Dear Nishant (Stratos) - Hello after ages! How are you? I am very happy to read the review, thanks!

Best regards,

Behram Dhabhar

[tharian]

That was one of the to-do's on my bucket list .
Lucky you getting a chance to drive a Prima and a race prep'd one at that.

Thanks for the crisp report and hoping for more from the CV world.

I remember a very old thread which you had begun about having a truck driving career in the West. I am totally up for it.

[Visran]

Wonderful review, I would love to see TATA's trying out their luck in international truck racing series.

[rahul4321]

Lovely review Stratos!!! I am envious!!! I love trucks as well as the B9R and B11R Volvo Buses. Torquey, Fast and can put some really good C segment cars to shame. Can I just ask in the picture you posted of the gear lever, what is the gear below the 'Reverse'?

[prakhar1998]

Amazing review Stratos.
How quickly does this monster reach the 100 mark?

[Stratos]

Originally Posted by prakhar1998

Amazing review Stratos.
How quickly does this monster reach the 100 mark?

Strictly depends on how fast you change gears . But jokes apart, I would assume that the Prima touches 100 km/hr somewhere near the 25 second mark. Sorry, I did not get an opportunity to check the time accurately.