Hey guys! Recent lurker, first time poster here! I purchased a 2000 camaro 3.8 recently for $1000 which came with the running v6 with blown intake gaskets, a disassembled '99 LS1(block has been sold as well as rotating assembly, making me in this car for roughly $100 to the good) and also came with a 5.3 LM7 with harness, all modules, starter, flex plate, and so forth. Engine was totally sludged up so I disassembled it and it's at the machine shop. I dropped off the 706 heads before realizing they were castech's after looking back at photos I had taken of everything during disassembly. I called my machinist and asked him to hold off on the heads and I ended up dropping off the 853 heads from the LS1 for him to mill down .030 to keep compression similar to the 706's.
Here's my question: with those heads being milled down .030" combined with the larger intake valve size and the Texas Speed Dumpster Fire .600 lift cam I'm running, will I have clearance issues? He hasn't started on the heads yet so if I'll have an issue I can still make changes.
Thanks in advance, and looking forward to being a highly active member here!

 

If you are near a pick-and-pull salvage yard go get a pair of 799 heads from a 4.8 or 5.3l truck. They flow a little better than 862 and 853 and will raise the compression without milling...no worries about piston to valve contact either! I doubt you would have had any issue though

 

Thanks! I'll check it out if I can find some at the yard. Looks like the combustion chamber is still 3.5cc larger than the 706 heads so I'd still have to mill them but not nearly as much. If I can find some I'll snag them and drop them off too. My main concern was the clearance between the pistons and the larger intake valves in the 853's at .600 lift. This whole car is a good bit more involved than the Hondas I'm used to, still have a lot of issues to iron out... transmission being the biggest, fuel delivery, rear end, engine management haha

 

Most LS 5.3's and 6.0's i've seen have had piston decking of +.008 to +.010. Hard to say about ptv clearance but most times it will be fine unless a super wild camshaft is being used.

Make a new post with the camshaft card info so the guru's here can see and ask about PTV clearance. Will the block deck be cut? Aftermarket pistons can make a difference in deck height. You can use head gasket thickness to help also

 

Deck will only be cleaned up unless he finds reason to need a shave. I'm hoping to use the same compressed thickness MLS gasket, but if I end up having to go a little thicker to allow clearances then that'd be fine lol. I'll take a photo of the cam card when I get home this evening and add it to the original post, but in the meantime just for reference its the 224/228 114lsa Texas speed cleetus mcfarland dumpster fire cam

 

My LQ9 6.0l had piston out the hole .009,.010. I am running a SRD designed CamMotion cut camshaft 228-232 .602"-.598" 112+2. My 243 heads were milled .030" when TEA did their fancy work to them. I had no issues with PTV clearance. I doubt you will with the camshaft you are choosing to run. Normally a wider LSA will increase PTV clearance