I installed a DC Sports shift knob – a 400g beauty made in the USA.
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Hey folks,
Time for another update on my Altroz iTurbo build – and this one’s particularly exciting. While the changes might appear small on the surface, they’ve made a tangible difference in real-world driving. This post covers improvements to the tune, ignition, suspension, braking, intake system, ICE, and even a little cosmetic touch – all done with a focus on enhancing driver feel and practicality.
ECU Tune: Boost Control Sorted, Punch Restored
Let’s start under the hood. The Revotron 1.2T uses a vacuum-actuated internal wastegate – a basic mechanical system, unlike the electronically controlled (PID) setups in cars like the i20 Turbo or VW TSI engines. This older-style system struggles with precise control, especially under load. In my case, the wastegate would occasionally oscillate between open and closed, causing overshoots and undershoots in boost pressure – leading to inconsistent power delivery and even triggering an ECL.
After spending more time with the EE tuning team, the issue was diagnosed and resolved. The solution involved fine-tuning the map and slightly adjusting the preload on the wastegate spring – allowing the turbo to hold boost longer before the gate begins to open. The result? A solid 1–2 PSI increase in boost under load across the range.
This, combined with spark and fueling adjustments, has made the car noticeably more aggressive and raw – even more so than the earlier Stage 2 map that was dynoed. No dyno graphs this time, but the seat-of-the-pants feel is undeniable.
Spark Plug Setup: Subtle Changes, Big Difference
Previously, I was running NGK LKR7BIX-P Iridiums, which are one heat range colder than the stock Bosch YRME plugs. Out of the box, the NGKs come with a gap of around 0.9mmcompared to the 0.78–0.8mm factory spec of the Bosch units.
These NGKs worked fine with Stage 1 and the earlier Stage 2 tune. However, with the new, more aggressive map, I started experiencing occasional misfires and slightly sluggish throttle response. Suspecting plug gap, I had them cleaned and regapped to 0.7mm – and that made a world of difference.
Now, the power delivery is crisp, clean, and responsive. This proves how important proper ignition setup becomes when you’re running higher boost levels.
Suspension: Altroz Racer Springs – A Missed Opportunity
Curious about the new Altroz racer springs, I decided to try them out. Being a direct fit with stock ride height, and marketed as performance-oriented, they seemed promising. But on the road, I was disappointed.
The springs are identical – but the stock one has 1 brown dot while the racer ones have 3 orange/red ones
While they did offer a more comfortable ride – passengers appreciated this – the springs dulled the car’s handling. Turn-in felt vague, mid-corner feedback was nearly absent, and although braking dive improved and the body roll decreased noticeably. Steering feel reminded me of a Punch EV – dependable, but uninspiring.
Possibly due to a higher front-end spring rate (maybe optimized for the Racer’s slightly heavier engine bay), but regardless, the difference was stark. After a long drive from Bangalore to Goa on these, I eventually switched back to stock springs – and instantly felt more connected to the road.
Brake Setup: Bigger Rotors + Brembo Bite
While at EE, I explored brake pad options that matched the larger diesel-spec front rotors. Turns out, Fabia/Polo pads are a good fit.
I upgraded to Brembo brake pads and replaced the fluid with Brembo DOT 5.1. Compared to the stock pad and ENV6 fluid combo, the difference is night and day:
- Daily driving: Smooth, quiet, and progressive
- Hard braking: Absolutely ferocious bite
- With Michelin tyres: The car anchors itself under hard braking
Pracitcally the same pad!
Intake & Thermal Management Upgrades
Next up, I installed a performance intake from HPIcomplete with a proper mount. It’s not a cold-air intake per se (no sealed box or ducting), but it does a great job pulling air while making all the right turbo noises. Combined with a decat setup, the car is now audibly more exciting – you hear spool, induction, and flutter when driving with the windows down.
Additionally, I wrapped thecold-side SS304 intercooler pipe with fiberglass heat wrap. This pipe runs close to the downpipe and was picking up radiant heat. Though my upgraded intercooler already helped, this wrap has further reduced intake temperatures, and I haven’t experienced any noticeable heat soak since – even in stop-go traffic.
ICE Overhaul: Pioneer HU + Full Signal Control
I’d been experimenting with a custom EQ mod on the stock head unit by trying to mod the firmware update file to better suit my Sony is speaker setup. While it initially worked well, a rat bite caused wiring damage that shorted something in the cabin, bricking the silverbox. Only the display would light up, with all options greyed out. The service center blamed the rat, though it’s hard to ignore Tata’s occasional electronic gremlins. So I went to Clarity Car Audioand had a Pioneer 6650BT head unit installed with:
- Coupler-to-coupler wiring (no cutting)
- Hiworld CANBUS to retain reverse cam, parking sensors, dimming
- Steering control retained via hardwiring
- Also added a wiring tweak to retain “delayed shutdown” behavior (HU stays on till the door is opened). (thanks to the service manual)
- Planning to add a time-delay relay to prevent HU power loss during cranking
Now running RCA outputs to the amps, with proper tuning via 4v pre-outs, EQ, and time alignment. The system sounds fuller, cleaner, and better balanced, with far better control over high and low frequencies. The subwoofer integration feels seamless, offering tight, omnidirectional bass that doesn’t overpower vocals.
Final Touch: DC Sports Weighted Shift Knob
Finally, I installed a DC Sports shift knob – a 400g beauty made in the USA. It complements the silver trim on the dash perfectly and has transformed shift feel.
The added weight helps smoothen out shifts and reduces the notchy, clunky feel of the gearbox. While the slight synchro resistance is still there in certain gears, the momentum from the knob helps mask it significantly.
A small but impactful upgrade!
All in all, this round of updates has made the car more exciting, responsive, and practical – the tune’s sharper delivery, the confidence-inspiring brakes, or the refined audio experience.
With the car closing in on 80,000 km, the build feels more or less complete. It finally reflects my vision of an ideal daily driver — comfortable, capable, and with just enough edge to keep things interesting when you want it to.
Drive On!
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