As I search for that illusive '71-'76 Olds Custom Cruiser I'm set on, a local mechanic warned me to be careful with car's from the '70s that used to run on regular fuel. He says they don't do well with today's grade of unleaded fuel, and that if the car I eventually get hasn't already been worked, an engine rebuild will be in order. And about rebuilding the 455 V-8 engine, he wished me luck, saying it's a dying art. Few here in the Bay Area, he said, know much about that particular engine's idiosyncrasies. Is anyone familiar with this fuel issue and its affect on cars from the '70s, particularly the GM 455 V-8? How big a concern is it? And if he's right, does anyone know a resource for a reputable engine rebuild? Appreciate any input.
The only real concern is the valve seats. A full engine rebuild is not required. My 1974 Toyota has been running on unleaded for 70K+ miles and showing no signs of problems. From Jim Hand's High Performance Pontiac articles. http://www.fortunecity.com/silverstone/pontiac/101/build/comp.htm BTW, Jim Hand's personal ride is a 473 CID Pontiac wagon. http://www.pontiacstreetperformance.com/psp/rebuild455jh00.html
Did your mechanic recently acquire a big expensive boat or have kids in college? You can run a lead additive on the cheap if you don't feel like rebuilding the heads with hardened seats. You will be fine (well your wallet might not be, but physically you will be fine).
Find a mechanic who has a clue. Starting with the 1971 model year, the feds required all cars to be able to run on low-lead (and later no-lead) fuel. ALL Oldsmobiles built from the 1971 model year onward have induction hardened seats from the factory. Your "mechanic" is clueless.
GM used hardened valve seats beginning in '71 (for low lead fuel) if memory serves me correctly. It's simple enough to install them when doing a valve job anyway so not to worry. EDIT: What Joe says^
I've been running 87 octane unleaded gas purchased from the BP station on the corner in my '73 Custom Cruiser for the 1.5 years I've owned it. It has the 455 V-8, and I've never had running or driveability problems. Just keep your engine tuned properly and don't worry about it.
The first thing I was wondering is what is so mysterious about an Olds 455. With the number of Cutlass 4-4-2's out there, having one rebuilt is a snap! There is nothing esoteric about any of the G.M. engines. If your mechanic is claiming that a simple rebuild on an Olds engine is a dying art, he needs to bout of the business altogether. I wouldn't trust him to do an oil, lube, and filter. Based on the age of the engine, you may need to run 89 octane instead of the regular 87. Keep in mind that most, if not all, G.M. cars were factory equipped with catalytic converters from 74 on, so must use unleaded fuel anyway.
Olds motors DO have some differences from Chevy motors and Chevy-centric mechanics and machine shops frequently screw them up. Biggest difference is the non-adjustable valvetrain that requires careful setting of the valve tip height during a valve job.
I was well aware that there were specific things to watch out for with the Olds engine. My point was simply that there shouldn't be anything so strange, or that the engine is so rare, that the rebuilding skills are dying off. Of course care must be taken when choosing a shop to make sure that they are familiar with the idiosyncrasies of the Olds engine. It is the same a finding a shop that is familiar with the Ford AOD transmission. A shop more familiar with the Turbo-Hydromatics is going to get the shift points all screwy. Find a Ford-centric shop, and no problem at all. Not a dying art, merely a somewhat specialized one.
455s Yes, these idiosyncrasies are what I need to know more about. For instance, one Buick Estate owner wrote me that Buick's 1976 455 was better than any of its prior years because they made larger oil gallery passages throughout the engine, which addressed oil pressure issues. I'm not a mechanic and unsure if that means to avoid the Buick 455 from before 1976, but it sure helps to know what to look for. So, I appreciate the insights on the different engines--especially (but not limited to) the Olds and Buick. Thanks, everyone.
Here's some info ... the second link gives a lot of general info on Olds engines... http://www.442.com/oldsfaq/ofe455.htm http://www.442.com/oldsfaq/ofeng.htm
