TT5,
Aim for zero lash....theoretically. Whatever, semantics, playing with words. If somebody aims for zero lash...& attains it, then they have zero lash which is bad for reasons already explained. I do not know how much more simple I can make it.
Brule was doing a dyno comparison, maybe his zero lash was in that context, not on an engine that will be driven for 000s of miles.
See if you can find anyone else who recommends zero lash.....
Your claim & Dale Davies claim that hyd cams do not have clearance ramps is nonsense. So is the claim that the roller will get beat up because of lash. You evidently know little about cams. at low speeds, hyd lifters [ FT & roller ] have enough time to bleed down such that as the valve seats, there is clearance [ lash ] in the valve train. Bleed down lifters like Rhoads, you can hear the noise it makes. The rollers are not getting beaten up.
Clearance ramps. Both sol AND hyd cams have them. Hyd cams haver much shorter clearance ramps [ shorter duration ] but they DO have them. This is why it is so important when running sol lifters on a hyd cam to keep the lash low.
As for not using sol on a hyd lobe, Comp Cams have a number of lobes that can have be used with sol or hyd lifters: Max area lobes, DHI & DHX lobes.
A Comp Cams 288* hyd roller cam I degreed measured 307* @ 0.002" tappet lift; 288* @ 0.006" [ the adv duration ]. Clearance ramp of 19* duration, NOT zero. Another one: hyd FT Isky cam 280* adv duration [ @ 0.006" tappet lift ], measures 295* @ 0.002", so 15* ramp duration. Comp Cams hyd cam 286* @ 0.006" measured 305* @ 0.002" tappet lift.
