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Double Roller Timing Chain?

1986 F-250 7.5L BB, needs a new timing chain- what’s the difference between double roller or single roller in terms of performance? It’s already got at least 175k miles on it, I’m not really expecting to break another chain with this truck…

One is high and the other is not.No change in proformence.Stay with what came in it. Good luck.

As I recall, these engines came with Morse timing chains, which have no rollers…OHC engines like the newer 4.6L and 5.2L OHC Ford engines use roller chains.

A double roller chain is less prone to chain stretch over time as compared to a single roller chain. This aids in keeping the cam and ignition timing a bit more precise.

Sometimes a double roller chain and gear set will be listed in the performance section, when the OE didn’t have it. In this case ( for high performance ) you may find that the cam timing is slightly advanced in relation to the crank. I’ve seen this true with the ford 302 / 5.0 L but not sure what you get with the 460 set.