Our new heads (which will be called "Super Stealth") use a stock length valve. When you get into longer valves, you must raise the valve cover rail by a corresponding length, which also increases the overall exterior height of the head. At that point, it becomes impossible to keep the factory 'look' on the exterior of the casting. Plus, because the bowl area was opened up considerably and port roof was raised as far as possible, we were getting flow numbers that we wanted without feeling we needed to go to longer valves.
On the question of pushrod clearance, the "dog leg" or turn in the intake ports has been almost completely removed in these heads. This requires them to use a .650" offset intake rocker. We chose this offset because it is identical to what the Edelbrock Victor head uses, ensuring there are many rocker arm manufacturers (Harland Sharp) etc, making these. We also carry our own version available on our web site at:
http://store.440source.com/650-Offset-Aluminum-Roller-Rockers_shafts-15-Ratio/productinfo/200-1125/Because of the offset rockers, we had to completely relocate and enlarge the intake pushrod holes. We made the holes as large as we could, and out of all the test engines we used, not a single one had any pushrod clearancing problems. However, (as they say) YOUR MILEAGE MAY VARY. You should always do a mockup before final assembly and check for clearancing. Too many factors affect pushrod placement to put an engine together without checking it first. Also, our 1.5 rockers outsell our 1.6's by a factor of at least 10 to 1, so all our test engines were fitted with 1.5 rockers. So using 1.6's would likely increase the chances (if any) that clearancing would be required.
Hope this answers your questions, thanks for your interest. These new heads have been several years in the making. Eventually we hope to have a CNC version available from Jeff.
. I probably could use a little more cam with them.
My ootb set were from the first batch they sold.
note to all these are SUPER STEALTH HEADS FROM 440 SOURCE FOR A STOCK LOOKING HEAD ITS DARN GOOD moral of the story is out of box not so great,just a little grinding & sandpaper roll work,dang good so far, more to come ck 