So since I can't reply to the old thread and I wanted to update and to ask a question here on the same engine, I started a new post. Mods can put them together if they prefer. This is the link to my first thread.
Here is my reply I typed out and was told I couldn't post.
So since I am obviously on top of my game with quick replies, here goes.
I finally got the 454 stabbed into the 74 crew cab and other than a super tight rear header bolt against the AC box, it went smoothly. The final idle vacuum was 15in/hg with just a little chop at 800 rpm. It ran super strong for a free no compression 454, though the speedway converter was junk (I should have known). It lasted for a few cruises around town, but after a couple John Force style 3rd gear burnouts the stock th350 wasn't up to the task.
So now it sits in my 74 crew cab in the backyard. The plan is to swap the 454 into our newly purchased 70 Sport Coupe Malibu L-48 4 speed car (built from 2 cars in the late 70s so not #s matching) and for the rest to donate parts to my wife's 74 malibu that I am working on.
Since I am never one to leave anything alone, I am having a set of 215 heads rebuilt and will add a Bowtie version of the Performer Rpm qjet.
So here is the question of the post, knowing that this engine only sees about 4K miles a summer and will eventually be replaced with a 496-505, would you add bigger valves? I don't plan on hardened seats and a trip to the strip will be few and far between.
Again, this is a 79 454 1979 lf-9 factory rated at 205hp 336ftlbs, unknown mileage, flat tops, stock oil pump, pink oil pump spring, erson e120721 296adv / 228 @ .05 intake, 306adv /235 exhaust @ .05 .542 lift 110 lsa cam, 800 cfm smab qjet, 2" hooker headers, 2 1/2 Exahust, 17749 dynomax mufflers.