Stock is 1.5, and hopefully the aftermarket also have less deflection than the stamped steel. Ouch $700, hope thats a bolt on kit with the rails and new hardware.
I talked to Peninsular tech and they might be using these, said they are using 1.6:1 or thereabouts, maybe 1.61:1 ratio. And they are adjustable on the pushrod. He also said the set comes with new performance pushrods, because the factory set were not consistent. The set of four shafts with rockers and pushrods would be about $600. They have sold some, but not on the site yet because most of their data is off the dyno so far, and want more miles in a truck before having them on the site for wide availability (with noise and efficiency comparison). All good results so far. He also mentioned would go well with their ported heads which are benched to 35% more efficient flow, but the porting is $468 per head
Their USA AMG heads with valves and springs (which is a special they have right now since they dont usually come with them) is $509 each. Cost a bit more than Clearwater heads from China, but maybe worth it for Made in the USA. So getting a set of performance heads is quite spendy, $2500 for set of ported heads with roller rockers!
He mentioned the precups in their heads are also different than the truck diamond precups. they have "marine" precups that are a bit larger, but beefier. He made reference to how porting the cup would lower CR a bit, but these were beefier in the corners and inside so it wouldnt. He talks my kind of language! Seems they have tested a good amount of precup porting. The guy was real knowledgable, actually been there and done that stuff, personal experience.
