upgrading to 1.8 rockers on boosted l92 headed 408?
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upgrading to 1.8 rockers on boosted l92 headed 408?
I've been doing some reading on ls3/l92 heads and have come to the conclusion that these heads like a cam with a little bit of lift. My cam has .595"/.608" 232/240 115 LSA on a 1.7 rocker. The springs are good to .660". Does anyone have any clue if I would benefit from upgrading to a 1.8 rocker?
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You would see a small gain but you would need to be carful with PTV clearance issues. You would be better off getting a cam with higher lift ground to specs that would suit your turbo.
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just leave it as is, it will valve float earlier with the heavy rocker and the last thing u want is float in a boost application. u would be better off shimming within 60 thou of coil bind, it will be a better deal that way. stick with the stock rockers.
#5
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I think I answered your question on facebook when you posted this on the Richmond Performance Musclecars page.
Here it is so others can see this information as well....
It will also change a lot more than lift going to 1.8 rockers. You will substantially increase the lobe acceleration of the lobes you are using which will need an increase in spring pressure to control and sometimes even with increased spring pressure it still isn't enough because other parts of the valve train are too heavy and not light enough to be able to withstand acceleration values that quick thus resulting in valve-train instability and valve float. And if you have L92 heads with L92 valves you really don't want to do that as those are quite possibly the largest heaviest valves that GM made for the LS cylinder heads
Here it is so others can see this information as well....
It will also change a lot more than lift going to 1.8 rockers. You will substantially increase the lobe acceleration of the lobes you are using which will need an increase in spring pressure to control and sometimes even with increased spring pressure it still isn't enough because other parts of the valve train are too heavy and not light enough to be able to withstand acceleration values that quick thus resulting in valve-train instability and valve float. And if you have L92 heads with L92 valves you really don't want to do that as those are quite possibly the largest heaviest valves that GM made for the LS cylinder heads