Our Valve Springs are designed and manufactured to specifically fit the envelope of a Porsche application not a spring from another use. It operates a higher natural frequency than the original spring for racing and at the very least minimizes damage from over rev in track day situations. 911, 914, 930, 993-must use 8mm Ti retainers and Aasco Seats.*Not an...
Our Valve Springs are designed and manufactured to specifically fit the envelope of a Porsche application not a spring from another use. It operates a higher natural frequency than the original spring for racing and at the very least minimizes damage from over rev in track day situations. 911, 914, 930, 993-must use 8mm Ti retainers and Aasco Seats.
*Not an OE replacement, requires use of HP10T9 or HP10T8 retainers.