Fine Tuning a 360 Magnum with a Brawler "Double Pumper"
How much preload were you running with these lifters on the other cam?
So I only ran the Hughes lifters on the comp cam for about 30 minutes before the engine seized up. On that setup, I was running about .040” preload. 6.76” zero lash, 6.8” rods. When I transferred them over I put in 6.9” pushrods and they zeroed at 6.81” with the new cam so it was .090” preload which is in spec for iron block, iron heads with the 5007 lifters.
I did just put in 6.936” pushrods which would give me .126” preload, which is in the specs of what Hughes said in the cam instructions. It is still clicky, and it sounds like there is one cylinder that is louder. For simplicity let’s say the engine is idling at 600rpm, that means that the engine would rotate 10 times a second, and the cam would rotate 5, meaning that if there was a bad cylinder noise I would hear it about 5 times a second, which I do.
The ONLY thing that was a carry over between the previous engine setup and this one is the Harland 1.6s, and given that it makes a similar noise to what it’s before I rebuilt the engine, I feel like I have a culprit. I’m still going to let everything break in a bit more before I start actually replacing things, but correct me if I’m wrong it really seems like it could be the rockers. I didn’t think about doing this when I had the covers off, but I did put a screwdriver to my ear and went around the top end around the exhaust and intake, and I can hear the tapping.