Clearance issue with Harland Sharp roller rockers

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70Duster340inWA

70Duster340inWA

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My 340 has the original 1894 casting heads with dual valve springs and Harland Sharp roller rockers. I believe the cam is an Isky hyd 292°.505 lift cam but I haven't confirmed that. I have not torn the engine down since I bought the car a few years ago. I started getting metal to metal noise about 100 miles ago and parked the car. I pulled the valve covers and the rocker assy from the pssgr side and found the rockers are galled on the underside of the valve side of the rocker. It looks like the spring/retainer are interfering with the rocker. I need some suggestions for spring sets and rockers that have propper clearance.
 
70Duster340inWA said:
My 340 has the original 1894 casting heads with dual valve springs and Harland Sharp roller rockers. I believe the cam is an Isky hyd 292°.505 lift cam but I haven't confirmed that. I have not torn the engine down since I bought the car a few years ago. I started getting metal to metal noise about 100 miles ago and parked the car. I pulled the valve covers and the rocker assy from the pssgr side and found the rockers are galled on the underside of the valve side of the rocker. It looks like the spring/retainer are interfering with the rocker. I need some suggestions for spring sets and rockers that have propper clearance.
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No, you need to correct the rocker geometry. Contact Mike at B3 Racing Engines. He will show you the way.
 
a 292 isky is a BIG cam bigger than a 293 MP as far as duration is concerned
but in reality not much lift/ area for that much duration
good news is that they rev well and are easy on the valve springs
you do need to talk with mike read his 4 tech articles on his website
do not b surprised if your guides and vj are shot
what springs and diameter
you could switch to beehives but that does not solve the real problem (geometery)
 
We had the same problem with T&D rockers. My son mad a fixture for clearancing them and mounted it on a rotary table . They did not hit when opening they hit while closed. Not one of the rockers were cut the same from the manufacture. So checking one or two won't help we had to check them all and they were all different.

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Oldmanmopar said:
We had the same problem with T&D rockers. My son mad a fixture for clearancing them and mounted it on a rotary table . They did not hit when opening they hit while closed. Not one of the rockers were cut the same from the manufacture. So checking one or two won't help we had to check them all and they were all different.

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The lad does nice work!
 
Measure the OD of the springs.

SB HS rockers are only designed to clear 1.500” springs.
 
still looks like a geometry problem, or both
let's check the stripe on the valve tip when he gets it together
 
Man you might have taken a lot of strength out of those rockers by doing that. Mike from b3 solved my clearance issue I am running 1.58inch springs. It's all about the geometry :D
 
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