Quote:
Originally Posted by Sieg
So 550 - 575 at the crank is a reasonably safe target?
What are the LS3's common stress related failures?
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Throw the connecting rods away, forged pistons, some valve train components and mods to oiling system passages. I haven't built a lot of LS motors but, my friends machine shop has, including his sons kick ass KOH off road buggy engine. If your going drag racing, it's one thing but, if you plan on hitting a road course for 20 minute lapping sessions and extended high RPM running, cooling systems upgrades would come into play in my book.
When building my GS Vette LS3 I went with Mahle pistons, Manley forged rods (lighter than the GM powder metal crap rods) hand ported the heads, changed valves for hollow stem stainless stuff (but the OEM LS3 intakes are pretty nice and light) I drilled the plastic lifter guides for better oil drain back, used better lifters, pushrods, valve springs, and most importantly looked at all the poorly intersecting holes in the oil passages of the block/oil pan and ported/smoothed the transitions as I anticipate extended high RPM operation of my build. You won't find the deficiencies of the LS oiling system in a drag racing environment but, take that same modified motor to a track and you will. After all I went through on the LS build, I think I should have just called up Donvon Engineering and ordered an aluminum GEN1 block. In my opinion the oiling system of an LS motor isn't as good of a set up as a GEN1.