[Formulajones]

The only engines I've ever been involved with that only like 26-28 degrees of timing on pump gas are LS engines. They generally came with factory timing in the 22 degree range but dyno testing showed they really responded to 26-28 degrees and a rare occasion 30.

All the old dinosaur engines I've built and tuned, including engines that have had more modern chamber cylinder heads, has never responded very well to timing as low as 28 degrees. I always shoot for zero deck and tight quench engines and as much compression as I can get away with on pump gas and the camshaft being used. Even with modern heart shaped combustion chambers it's been rare from my experience that they made best power on the dyno any lower than 32 degrees, and most of them are always up around 34-36 as the norm, sometimes 38-40. There is no rhyme or reason, but the engine would have to be dyno'd or track tested if you really want to find out what it wants.

Honestly it sounds to me your engine builder is being extremely cautious and erroring on the light side for timing not knowing how you're going to treat the engine. Can't say I blame him, when you're in that sort of business.