Tuesday, February 1, 2011

More Torque for Hyundai Getz

I bought my Hyundai Getz in early 2005. I was happy with the space, finish, build quality, easy ingress and egress and even the boot space. But I always felt that the engine lacked punch. On the high way it had poor overtaking speed particularly over 100 kph. I am not a particularly spirited driver but I do like to drive at a decent clip and not having good overtaking speed can be a hazard.

So I decided to seek help. My friend Raj Hingorani is one of India's top tuners. We decided that we should improve the breathing and the scavenging of exhaust gases. We removed the stock air intake and replaced it with a K&N cold air intake.

K&N Cold Air Intake
Here is a little tip about replacing air intake. Disconnect the battery for about 30 mins. This  deletes the airflow data in the memory. Change the air filter and re-connect the battery. Start the engine on full throttle and release it as soon as it hits about 5000 rpm. Take the car for a drive for about 5 mins. The new air flow data is now logged in the memory.

The immediate result was that the engine was revving more freely and there was a marginal improvement in acceleration as well as low speed traction.

Raj then designed an exhaust system. My requirement was low end and mid range torque. Raj designed a 4-2-1 header with long secondaries and 15" primary pipes. He has a fantastic  fabricator who built it in a day! We then decided to coat it with ceramic coating. Ceramic insulation stops the heat from escaping so the hot exhaust gases retains the temperature to large extent and flow out quickly; hot gases being lighter flows out faster. The trick is to get the exhaust gases out of the system as quickly as possible.

Exhaust Headers
Again a little tip on headers: the diameter of the pipes are critical for getting the full benefit. To large a diameter slows the gases and too small a diameter does not allow the gases to fully exit the combustion chamber. The principle is to scavenge the cylinder of all exhaust gases so that the incoming fresh charge does not get contaminated and has the opportunity to fill the cylinder. Secondly the primary and secondary pipe lengths must be properly calculated so that the pressure pulses created by the opening and closing of the valves and the sound waves are complimentary from each cylinder. Calculating these lengths for the kind of performance required requires an expertise best left to the tuners! Be clear to give them a proper brief if you want the headers to match your driving style.
A properly designed header should improve the power output between 8-12%. When we went for a test run I could immediately notice the improvement in acceleration, more importantly the car was much more fun to drive. Through the gear acceleration had improved noticeably.

Most exhaust silencers compromise on power for the sake of reducing sound. Motor vehicle laws do not permit sound beyond a certain level. I am not sure if this applies to super cars and bikes which are incredible loud! So I went in search of a straight through silencer with high flow through capacity. Its no point having a header with a silencer which has poor flow rates!
I found a Remus box from Methods Automotive which had excellent flow rate.

Silencer - Remus Tail Box
It also produced a nice deep exhaust note which both Raj and I liked very much. So we fitted it. Now the intake and the exhaust were working to almost their full potential.
Raj suggested that we also change the plugs to more efficient Bosch Platinum Iridium plugs. Luckily Raj had a few sets and I took one off him!

Bosch Platinum Fusion Spark Plug
Now all the changes that we wanted had been done. It felt like the Getz had a bigger engine. I would be lucky if I could get more than 11 kilometers to a liter of petrol. I wanted to check the fuel efficiency too.

I took the car to Mysore and onward to Coorg. For the first time I felt really good driving the Getz. I could easily overtake at speeds above 120 kph. More importantly I did not have to frequently change gears. Even on the hills in Coorg it climbed effortlessly and I really felt that spending the money was worth it.The best part was the fuel efficiency improved by 1.5 kmpl. That's almost a 15% increase in fuel efficiency!

Then the best thing happened. Somender Singh is an old time buddy of mine. An old hand in racing, modification and tuning, Somender has a US patent on a very simple invention. Its called Singh's Grooves.

Go to www.somender-singh.com to find out what it does. On one of my trips to Mysore I stopped at his place. He drove the car and said that he would like to cut the grooves on the cylinder head. Basically the grooves significantly improves the speed at which the combustion flame spreads inside the combustion chamber as well as the uniformity of the combustion. The net result is that the torque increases at very low engine speeds and more importantly reduces the emissions to the extent that even without the cat the emission norms are met! I left the car with him.

After 4 days he came back and the results fascinating. The torque spread is so wide that I can drive on 4th and 5th at around idling speed and accelerate smoothly without having to change gears. Of course the acceleration is also improved. But I am not racing on the streets!

I had been contemplating changing my car, but now I don't think I will. Advaith Hyundai takes very good care of the car and they maintain it very well. More importantly I enjoy driving the car, so why change?

This blog was guest written by S.G. To know more visit his blog More Torque.

In case any one of you want to get in touch with Raj send him a mail at  powerwheels@hotmail.com