Buick 455???

[perezmaximus]

I need to know if there is any diffrence between the Buick 455, pontiac 455 and oldsmobile 455? If there is then how can I know wich is what by looking at a plain engine?Thanks

[The Old Guy]

Buick has the distributor in front, and the others have it in the rear

[NTX5467]

Those engines are completely unique items unto each other.

As mentioned, the "front distributor" is a definite (in GM) "Buick feature" that the others do not have. Also, each one will have their own family identifiers (valve cover shapes, intake manifold configuration (even with a common type carburetor), how the spark plug wires route, the exhaust manifold configuration, a/c and alt and ps braketry, and air cleaner and snorkle configurations. Once you know what you're looking at, it's pretty obvious.

The "front distributor" is significant as it allows a more accurate spark timing situation. In the book that Smokey Yunick wrote, he mentions that a distributor mounted on the rear of the block (at the back end of the camshaft) will see much more inaccurate spark timing due to twist "harmonics" of the camshaft between the front of the camshaft and the rear of it. Might not amount to much in a street engine, but in a high rpm race engine, it can cost power.

The "front distributor" also can make the engine "taller" in the front, which can affect the height of the front sheet metal of the car. Having it back, near the cowl/firewall (which will have a certain height to it anyway), can make packaging the engine "better" in the vehicle and also allow it to fit a wider number of chassis/body combinations (i.e., Corvette, passenger car, truck). But, of course, the "front distributor" is much better when changing contact points and other related items as a part of the normal maintenance of those earlier times.

A great resource for what these engines look like is the Petersen "Book of Engines" annual series. It started with the 1965 model year and was published each year after that until the middle 1970s (approx). Each USA vehicle engine is detailed in the book, with the SAE specs listed in chart fashion at the front of the book. Lots of neat information and historically correct pictures/drawings of each engine family.

In more recent times, some of the Hemmings magazine publications have done a "feature engine" per issue. Many pictures and such in these articles too. They started a few years ago.

If there is a large library (city or university operated) near you, you might check out the Automotive section for a Motor or Chilton repair manual. These would cover many years and all USA makes, typically. There should be some pictures in them too. Look for the ones that cover the 1950s-60s-70s vehicles. These manuals would be oriented toward the chassis and powertrain items rather than specifically body repair items.

Hope this helps . . .

NTX5467

[Guest BJM]

I have rebuilt the Olds 455 but not the Buick. Olds uses different rocker system I think. Location of spark plug different and I know Olds adjsuted compression fromthe piston, not the head chamber, not sure about Buick. Manifolds are different, as mentioned the Distributor location different - then that effects every other component running off the camshaft.

The 3 motors were all derived from fresh designs in the mid sixties and at that time each division still had seperate engineering teams designing brand only engines (with probable pride associated).

I wouldnot try crossing any internal components, if you were thinking about doing that. The confusion sometimes lies in the fact that a "corporate" TH400 will bolt up to any of these Big Blocks so we often see Buicks for sale with Pontiac 455's or vice versa.

[Guest BJM]

If you do not have experience about which is which then remember what others have said about the Distributor in front for Buick. The Oldsmobile has a unique shape to it's valve covers and a flat front cover that the water pump and accessories bolt to. The valve cover of the Pontiac is different but I don't have a photo.

[fly]

They each have unique displacements. The number 455 is just a general number. For example, I recall the Buick is closer to 456 cid than to 455 cid.

[perezmaximus]

Thanks guys!Really helpfull info.