High Rate Valve Springs for 996 and 997 Turbo

What are High Rate Valve Springs?

High Rate Valve springs keep your valves, lifters and cams together where they should be when increasing performance and power on a Porsche 996 and 997 Turbo, or any car for that matter.   They are performance springs with a higher spring rate and allow more lift for performance cams.

What are the specs of your Performance Valve springs for Porsche 996 and 997 Turbo?

• Drop-in with oem bases and hats
• Approximatly 20% increase in spring pressure depending on installed height.
• 268lbs at 0.1 in from coil bind compared to 225lbs stock.
• 100lbs at installed height for 0.5″ lift and 0.1″ distance to coil bind vs only 70lbs from an oem spring.  That’s 42% more pressure on the seat where you really need it to keep your valves closed when they should be!

Why should I run High Rate Valve Springs?

• If you’re building your engine for high power you want to use these to keep everything in place.
• When you increase the boost pressure, that increases the pressure on the back side of the intake valve, and the backpressure on the back side of the exhaust valve which are trying to push the valve open against the spring.  So a higher rate spring becomes necessary with high boost.
• If you’ve changed cams to a performance cam, they come with higher acceleration rates and more lift.  These springs can accomodate up to 12.7mm lift (0.500″) where the oem springs can barely go beyond stock 10mm lift.  The higher rate spring will keep up with the higher acceleration rates, keeping the lifter in contact with the camshaft.
• When you tune your car and raise your revlimiter, the higher rpms require more spring pressure to keep everything in place and the valves away from the pistons!

Can I use these on a stock engine?

Yes, they work well in a stock configuration as well.

How many do I need?

You’ll need a quantity of 1 in the shopping cart which containes 24 inner and 24 outer springs.

Do I need special spring seats, hats, keepers or valves to run these?

These springs are designed as a drop-in replacement for OEM.  They work with stock spring seats, spring hats, valve keepers and valves.   For higher lift, you adjust the installed heights with shims, or for even more lift the oem seats can be machined down a bit.

Need help with your build?

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