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I have T&D roller rockers custom built on my 451" Mopar stage 6 heads. Just wondering how long they will last on a street motor? Anyone have experience with them durability wise?
Thanks Brad

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It depends on how many RPM and what lift the valves have and type of lifter, flat tappet shifted at or below 7000 RPM should last a long time. I'm sure your crusing RPM will make a difference also, if ran at 4500 RPM for 10,000 miles will be a lot more cycles than the same milegae driven at 2700 RPM I put a set of harland Sharps on my old pump gas street Duster motor, I raced it more than I drove it on the street, I shifted it at 7000 RPM in each gear. I reshimmed the valve springs once and replace those springs after several years and never had a issue after replacing the adjusters with those rockers, they where the 1.6 ratio also . My motor had 250 lbs on the seats and 630 lbs opened on the solid roller cam. I stiffen the pressures up an the second set of valve springs(different brand) to 275 lbs on the seats and 680 lbs opened. Let us know the answers so we can hep you better with more information. I bought a set of the T&D for my bracket motor, I wasn't really impressed with them compared to the Harland sharps, they both had lift differences at the valves on the same cam About .030 differences checking with light springs between the most lif and least lift on the same lobes, probally worst with the good race valve springs