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compression test results

15 psi leak ? .... did you use a leakdown tester or was the guage on the compression tester moving ???
 
Assuming you mean 110 PSI of cranking pressure I'd say that's pretty low. Please clarify your leak down procedure.
 
Pulled valve cover off noticed valves aren't closing all the way tried. 030 shims under rocker rod made big difference on 3 cylinders except #5 was way to loose,would have tossed push rod. Just had head job done wtf. Is this normal. ?
 
Sounds to me like they replaced some of the valves during the head work and the stems have different lengths above the retainers/locks now... or like Scott74 mentioned, new seats that are at different or varying heights. You may need shorter pushrods and/or adjustable rockers now to get lash set up properly on each valve.
 
Sounds to me like they replaced some of the valves during the head work and the stems have different lengths above the retainers/locks now... or like Scott74 mentioned, new seats that are at different or varying heights. You may need shorter pushrods and/or adjustable rockers now to get lash set up properly on each valve.

I think your right, I measured distance from top of valve to top of valve spring retainer was getting big differences from valve to valve. I dont think valves are closing fully,plus when it was running could see huge flames coming out headers. What adjustable rockers do you reccomend?
 
I think your right, I measured distance from top of valve to top of valve spring retainer was getting big differences from valve to valve. I dont think valves are closing fully,plus when it was running could see huge flames coming out headers. What adjustable rockers do you reccomend?

Well, I ran into this same problem, but since things sat for years following all of the machine work, and I was in another state by then, I was unable to go back to the shop and say WTF. I had gone to a reputable shop, so had always been under the impression that it was done right.

I ended up going with Comp Cam's adjustable steel roller rockers because I couldn't really find any adjustable non-roller rockers for the 383 (they were discontinued I think), and I always really wanted to go with the roller rockers anyway. They have a kit that comes with new shaft and spacers etc, and not too expensive. I also had to get a new set of pushrods to get all of the adjustments centered, but those are not too expensive, I measured the length I needed using an adjustable push rod, then bought set I needed. I like the ability to calibrate the lash perfectly on each valve now anyway, I never really liked the stamped rockers that had no ability to adjust.

Another thing you could do is have all the valve stems trimmed to match, then get pushrods to match that, that way they don't each have to be different. Just make sure you don't end up too close to the springs with the rockers. I didn't like the idea of shimming the entire rocker shaft out because it changes the geometry of the system so I never went with that option.
 
I thought they were reputable too.thanks for info. Gonna have to get a set. Why did you change push rods with the adjustable rockers. Thanks
 
Yea, 110 is pretty low, across the board they are all 110, think it's time to Yank it out. Sounds good however. Hmm. Time to bite the bullshit.
 
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