Quote:
Originally Posted by Bill S
My issue was I already have the Harland Sharp 1.65 roller rockers which are actually a ratio of 1.69.
Off the shelf roller cams would put overall lift too high for my valve length, causing retainer /seal clash.
Here are my cam specs:
Flow Tech Induction (Ed Curtis) designed; Competition Cams intake lobe # 3052, EX #3053, 230/240 @ 0.050”, I/E lift both at .321”, lift @ 1.69 = .542. Lobe separation = 114 deg, installed at 111 deg
Event at 0.050” lift , Intake open 4.0 deg BTDC, close 46 ABDC, Exhaust 57 BBDC , close 3.0 ATDC
Thankfully I still had a Mopar offset key kit P/N 4286500 in my parts bin to degree the cam.
To use the HT2148 lifters, cam base circle must be at least 1.135” diameter, mine measured 1.189”.
My cam base diameter combined with the .321” lift, put the lifter oil band is at the correct location. My oil pressure is spot on. I believe a cam lift can be up to .340” with these lifters and the dog bones.
Higher lifts require careful check to ensure the engine lifter bore does not have a deep chamfer having the oil band exposed at max lift. Plus the dogbones need to be machined per 68hotbird’s thread.
I bought Randy’s lifter which he swapped out the lifter plunger wire retainer with a C clip for $240.
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Thanks for posting Bill and should update the other thread of your progress. If you would be willing to list the rest of the parts you used that would be great (springs, push rods, distributor gear, ect). I'm likely going to go this route on a 455 so the info would be really helpful. And will also be using the HS 1.65:1 rocker arms.
I think the retrofit is perfect for its intended purpose of modest lift lobes and thanks Jim Leheart for coming up with the idea!
https://www.youtube.com/watch?v=fAKTh3uWBrE