Sunday Update #2 - Top End is Done Boys!:
Here are a couple pictures of the lifter blocks with the roller lifters in them - as well as our custom roller lifter. I can't believe the amount of work we put into just the lifters -- Don kicked butt on them! Hopefully our design works out - we even added pressurized oil to the axles, etc..
Chris Daniels and I put all the lifter blocks and lifters in yesterday - and set the lash. However, when Buddy was over in the afternoon, he and Chris were looking at the adjusters we used (vintage Harley stuff) and they seemed a bit funny.
I surged ahead and we put them all in. Buddy - having plenty of time in his truck, kept thinking about the adjusters and was wondering if they were square to the tops of the bodies . . . as we thought we saw something a bit off when installed???
This got us all worried, so I pulled all the lifter blocks, lifters and adjusters back out of the engine and surfaced every adjuster in my lathe to ensure they were all square. Most of them were a couple thousands off - so I only had to cut about .004 or so from the tops to true them. In retrospect, I will do this on every adjuster going forward -- as you have a nice polished surface when done (I polish with 400 - 600 grit sandpaper) and it does make it easier on the 'feeler gauge' lash setting procedure.
Needless to say - this was about a 6 hour operation . . . but I started very early.
1) Pressurized Lifter Blocks and Rollers: Took some work to figure out the dang pressurized oil line plumbing for the lifter blocks. I'd bought a crap load of AN fittings - thinking I could get them all in the tight valley area. Not a chance. I finally decided to make hard lines to go between the two blocks (side to side) and a flexible line to feed the blocks in the middle.
Took a lot of screwing around to come up with a workable plan - even had to weld up a 'custom wrench' to fit in a tight place.
2) Lifter Block Strut Support System: When Don, Buddy and I discussed the new roller cam design and the new lifter blocks, we pondered my concern that the only thing holding the lifter blocks in is two cast iron bosses that hang out in the valley of the block (for each block assembly).
It really concerned us that with the added stress of bigger valve springs and the side-load of roller lifters that we may be in danger. If one of those two bosses broke off, we'd drop the lifter block into the cam . . . into the crank and the whole thing would be a blender.
I originally designed a strut system to go all the way up to the intake girdle, but Don had a much better idea. He found some long ARP studs that could be modified to do two things:
a) Bolt the lifter blocks down -- so he threaded them all the way down.
b) Go up all the way out of the valley to a set of new custom steel valley cover plates where we'd tie the studs in. This top plate is like a 'stud girdle' for the lifter block studs. It picks up all four studs for each side (as there are two of them).
We have ARP nuts on both sides of the plates - and I put about a .001 to .002 crush on them. The theory is that we've now tied all four studs together and we've tied them into the block cover plate . . . hopefully this will help stabilize the lifter blocks and reduce stress on the block bosses.
It actually looks like of cool when you look at the valley - like something that you'd have in a WWII tank! Guess we're trying to be true to the engine's roots and wartime service!
Wish us luck - we have a HUGE amount to get done in a week - we're rallying the troops for next weekend.
More attachments in a second post . . .
B&S
Topic: XXO/BVGC '38 Chevy Coupe Build (Read 1031792 times)