These valve springs are much stiffer than stock and are a direct fit. No modifications need to be done for them to fit.
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Performance Valve Springs OM601, OM602, OM603 | Benz Injection

These valve springs are much stiffer than stock and are a direct fit. No modifications need to be done for them to fit. If you are running more boost and/or high RPM's on your OM60X, it is highly recommended to upgrade your valve springs. Otherwise,

Our valve springs are custom made to be 50% stiffer than stock. They are not just springs from another engine and are a direct fit. No modifications need to be done for them to fit. They are to be used with your stock spring seat washer and spring cap retainer. Simply remove your original springs and install these in their place.
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Performance Valve Springs OM604, OM606, OM606 | Benz Injection

Upgrade your Mercedes-Benz OM604, OM605, and OM606 engines with high-performance valve springs from Benz Injection.

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