I heard that for my 1970 Rivera engine I will need certain heads upgrades to run unleaded fuel. Is there any truth to this? Also keep in mind I'm rebuilding the engine so the heads are already at the machine shop and I'm not sure if it's a better idea to go with rebuilt heads or TA $1100 aluminum heads. So tell me what you think about that too.
stoutboy, It comes down to money really. The aluminum heads would be great and lighter too. Let alone the bigger valves to breath. But if your working on a budget I would have hardened seats put in your 70 heads and do a clean-up job. Leaves you more money for other items. Jerry
Most machine shops will install the hardened valve seats (for unleaded fuel) automatically. Ask your machinist, I strongly suspect he's planning on doing it. If not, ask him why not!
What year are your heads? Most hear 455s don't need hardened valve seats. Buick used such a high nickel content in their manufacturing process that the valve seats can go well over 100,000 miles with nearly no wear. To save money you'll probably only need a 3 angle valve job on what you already have. Unless the seats are niticably worn you can save your cash and avoid adding valve seats. Unfortunately, almost no shops out there have ever even seen a Buick engine or head, let alone worked on them. So what they know is minimal. Many Buick people who aren't too versed in Buicks as well aren't aware of their idiosyncracies. Most shops will tend to look at everything like a Chevy, where Chevy's metal is mush and NEEDS hardened valve seats. They then apply that philosophy to Buicks with negative results. I had the 100,000 mile heads on my 430 redone, and all it needed were the seats and valves cut. Same for my high mile Stage1 heads.
I know a good guy in Waltham Ma who knows Buick specs off the top of his head. He runs TC Auto Machine right near Moody Street. If you're near MA you might want to call Tommy up.
