PPR motorsport has been providing consultancy services to some companies for many years, these are factory race teams and international race teams.
The product we will talk about in this subject is valve springs! It is an article about how to use springs for high-speed engines.
As you know, the biggest reason for valve breakage is that the valves get stuck in the guide channel due to the movement caused by the floating of the valves at high speeds and then break.
This is an issue that has not been solved by automobile manufacturers and some professional race teams. I will be telling you about this unique R&D study we have done.
In order to prevent valve floating, you need to adjust the length of the valve guides well. In the design section, you determine the head diameter of the valves and a shaft diameter accordingly. This is a situation that should be directly proportional. In other words, if we need to go deeper into the subject! The eccentric lift value, the length of the valve neck and the valve guide length to prevent the valve from floating.
However, there is a forgotten situation! The widths that the springs should have according to the head diameter of the valves!!! In other words, the bearing situation made by the springs! when we look at the different cylinder heads we have seen over the years and the spring widths used in these cylinder heads, what we see has made us realize that there is a situation that all manufacturers in the world miss.

The R&D studies that started in January 2014 ended in February 2015.

Let's go into the subject a little deeper and give examples.
If we want to give you the closest example, one of the cylinder heads we first noticed was the cylinder head of Honda's K series engine. In these engines coded K20a2, the intake valve diameter of the cylinder head is 35 millimeters, when we look at the area where the spring is located, the spring itself is 28 millimeters, although 28 millimeters of spring width is enough for a 35 millimeter head diameter, the spring diameter width is not enough when this engine is modified and higher speeds are reached. On top of that, when the valve diameter is enlarged, a serious handicap occurs and causes the valve to float, that is, the valves are directly broken after a short time.
Now let's come to how we tested it. Let's tell you about it.
We set up a special electric cylinder head stand for the K20 cylinder head, we produced a chain connecting the intake and exhaust camshafts, standard valves, and the standard intake and exhaust camshafts. It was a short chain! Independent of the engine. We connected the oil system to the cylinder head, we used an electric pump so that the lubrication task in the head was more than normal. We tried to observe the valve float at certain speed ranges by powering the eccentrics with the help of an electric motor. In order to obtain technical data, we placed pads on certain places on the cylinder head to ensure that it would be transferred to the vibration test device, these pads were transferring the vibration data to the device.

In the tests we conducted, we observed that the vibration we saw at 8,200 rpm decreased by 47% when we increased the spring diameter from 28 millimeters and expanded the bearing area of ​​the spring. When we saw this value, we saw with our own eyes that we were on the right track.

Later, we applied these tests on different cylinder heads. The electric cylinder head dynamo showed us how beneficial it is to expand the width measurements of the springs proportionally to the valve head diameter with vibration tests.

After long R&D periods, we produced wide-diameter springs and the feedback from our customers about the products we sent to be used in different setup engines was very good.

Result:
When the valve head diameter and shaft ratio were selected correctly, we observed that the vibration caused by valve floating decreased even at very high speeds and the valves did not break and the valve floating rate decreased to almost 50%.
Finally, when we look at aftermarket modification parts in the world, all companies have tried to keep the width of the springs as factory values ​​and modify only the number of coils of the spring. What makes us special is that we do this type of R&D.

I, Kaan Güvenir, who wrote this article, am continuing my R&D studies for 20 years and I am sharing my experiences with you by proving them with tests.