LS3 88958758 head valvetrain upgrades
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LS3 88958758 head valvetrain upgrades I am building a 421 stroker LS3. I want to be at about 10.5:1 comp ratio. I bought a set of 88958758 heads for this build. I bought sdparts.com valve spring kit SD7660 with titanium retainers and dual springs that will handle up to .660 lift. I have not made a cam choice yet but it will be around .610 lift and 236 duration with a 112 lobe.
Here is my questions;
1. Should I used the stock valves or upgrade them.
2. I want to use an adjustable shaft mount roller rocker. Which one is the best?
Here is my questions;
1. Should I used the stock valves or upgrade them.
2. I want to use an adjustable shaft mount roller rocker. Which one is the best?
If those castings have the hollow stem LS3 valves as opposed to the standard L92 pieces, you should be just fine. Second, I know that shaft style rocker arms are like the cat's meow but really the GM rocker arm is by far the best bang for buck piece. It's very light at the valve, incredibly strong and with just a Comp or Lunati trunion upgrade kit they are very reliable !!!
They would work with your .625 ish cam although IIWY I'd consider a bit more duration....perhaps 242-246 range as you have all those cubes to gobble it up and still make it stoplight friendly.
They would work with your .625 ish cam although IIWY I'd consider a bit more duration....perhaps 242-246 range as you have all those cubes to gobble it up and still make it stoplight friendly.
