lunati gold dualss w/ ls7 lifters
12-31-2010, 10:16 PM
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lunati gold dualss w/ ls7 lifters OK I have been searching for last few hours and wanted to get some opinions. So now that I need to buy new springs due to a broken pac1218 and I have found a spring kit I'd like to get from Atlantic speed. I'm wanting to get the lunati 73925k1. My concern is fitment with stock heads and closed seat pressure being too much for my new ls7 lifters.you guys think this is a issue specs are below.
Spring od 1.306
153 lb @ 1.810
400lb @ 1.150
Max lift. 660
I am running a trickflow 238/242 @ .050 .595" lift with stock 241 heads.
I'd think this will be fine.I'm assuming 1.810" is installed hight? And 1.150 is at .660 lift?
And I will be checking install hight.last question is if stock install hight is 1.8" how do gain the extra .01" with stock valves?
thanks joe
Spring od 1.306
153 lb @ 1.810
400lb @ 1.150
Max lift. 660
I am running a trickflow 238/242 @ .050 .595" lift with stock 241 heads.
I'd think this will be fine.I'm assuming 1.810" is installed hight? And 1.150 is at .660 lift?
And I will be checking install hight.last question is if stock install hight is 1.8" how do gain the extra .01" with stock valves?
thanks joe
01-01-2011, 01:26 AM
#2
Joe,
In order to move the install height up, without machining the heads or replacing the valves, you'd need to get locks that will move the retainer up, or different retainers that will support the spring slightly higher...with either setup, you'll want to double check your rocker arm to retainer clearance through the full sweep on intake and exhaust.
Less installed height is cake, you can just shim the spring seat, more can be tricky.
Also...just throwing it out there...if they're saying there's 153 lb at 1.810, and you install them at 1.800...it's only 0.010...and it just means you have a little more seat pressure. IF your cam isn't bringing you dangerously close to coil bind...I wouldn't worry about the 0.010" difference...I'd just verify that they're all the same, and if not, shim them to match as best you can.
I'm also concerned with the pressure of the double springs on my heads as far as lifters too...so I'm going with Morels...they cost more, but they seem to be better suited to that.
In order to move the install height up, without machining the heads or replacing the valves, you'd need to get locks that will move the retainer up, or different retainers that will support the spring slightly higher...with either setup, you'll want to double check your rocker arm to retainer clearance through the full sweep on intake and exhaust.
Less installed height is cake, you can just shim the spring seat, more can be tricky.
Also...just throwing it out there...if they're saying there's 153 lb at 1.810, and you install them at 1.800...it's only 0.010...and it just means you have a little more seat pressure. IF your cam isn't bringing you dangerously close to coil bind...I wouldn't worry about the 0.010" difference...I'd just verify that they're all the same, and if not, shim them to match as best you can.
I'm also concerned with the pressure of the double springs on my heads as far as lifters too...so I'm going with Morels...they cost more, but they seem to be better suited to that.
01-01-2011, 03:03 AM
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Yeah thanks for the info that's kinda what I was thinking. Also on the lifters too but don't have the budget for the morels right now. But I also don't want to tear the top end off my motor again. Unfortunately there's no info out there that I can find about ls7 lifters. From what I'm told by a friend who used to be a machinest building race motors is you only want 30% more seat pressure than the stock lifterswhich in my case are ls7 lifters. So in that case I should be fine cause ls7 springs have #310 at. 600 and 30% of that puts me at 403 lbs seat pressure safely.
So if at .660" seat pressure on the lunatics is 400 lbs then wouldn't .595" be around 360 ish lbs? If so I should be fine. I guess my concern now is getting it all set up right for proper installed height
So if at .660" seat pressure on the lunatics is 400 lbs then wouldn't .595" be around 360 ish lbs? If so I should be fine. I guess my concern now is getting it all set up right for proper installed height
