Oldsmobile 455 data

Introduction

The Oldsmobile 455 engine was built in the USA between 1968 to 1976, and produced power outputs between 210 to 400 BHP and was used in everything from Saloon Cars to Muscle cars. The 455 is known as a very forgiving and long-lasting engine, not to mention being powerful. Spare parts are still readily available for this engine, especially in the States. There are a number of companies in the UK who can supply parts off the shelf.

Sources of Information

• A simple web search can provide lots of useful information. Some good sites are: [1] and [2]
• The Haynes Manual, Number 19025 "Buick, Olds, Pontiac Full Sized RWD models from 1970 to 1990" covers this engine. The club has a copy - should be on the bookshelf in the clubhouse.
• Ultimate American V-eight engine data book, 1949-1974, Books 1949-1974 By Peter C. Sessler. Available new and used on Amazon, but the text appears FOC in full online here on google books! Has information about all American V8 engines, a bit of background, etc, but - most usefully - how to identify and date an engine. Has block, head and manifold castings number information - an invaluable book when buying a replacement V8 engine. Also gives power and torque output data.

SSS's Original Oldsmobile 455 Engine

• Update: This engine was removed from the Skybrid/X Winch in April 2019 - this issue was that it was struggling to make any kind of power, would not idle, etc. There was an issue with the inlet manifold, and the valve seats were found to be worn. The bottom end is in good condition. With major parts like heads and blocks becoming rarer for these engines, it makes sense to keep this engine as spares.

The Oldsmobile 455 engine is what Tost specified and supplied with the original winch. The 455 engine that is in the Skybrid winch came to the club in the "Bus Winch" It proved to be powerful and gave good launches, but the crankshaft broke. It was removed from the winch, and once rebuilt with a new crank, was installed into the "Green Winch" (the Tost winch that was painted green and mounted on the back of an Albion Reiver lorry. In late 2007 the winch was removed from the lorry and sent to Skylaunch for conversion)

With data taken from websites and the Ultimate American V8 Book the engine has been identified and its year of manufacture found. More here on Identifying 455 Engine
SSS's Oldsmobile 455 engine's bottom end has been identified as being from an Oldsmobile 455 engine, built in 1970 at the Lansing plant.It doesn't appear to have any of the features that would identify it as being from a Toronado (a front wheel drive car) so its likely its from one of the standard Oldsmobile RWD cars, such as a Cutlass Supreme, 442, Delta 88. It'll have one of two compression ratios: 9:1 (320BHP @ 4200RPM and 500lbft @3200RPM) or 10.5:1 (365BHP @ 5000RPM and 500lbft @ 3200RPM).

• The cylinder heads have a casting number of 411 873 on them, and the letter J. According to the "Ultimate American V8 engine data book", this means that the heads have come from a 1973-76 455 engine.
• Engine number (found at the front LHS of the engine block, just under the head-block interface, is 30M106536
• The block casting number is found at the front top of the block just behind the water pump, to the right of the oil pressure sender unit. On this engine its 396021F - This casting number was used between 1968 and 1972 and is the most common big block type for the Olds 455 engine.
• So, it looks like we have the bottom end of a 1970 engine, and 1973-1976 cylinder heads.

SSS's Second Oldsmobile Engine

• Purchased in March 2019 as the Oldsmobile 455 engine in use in the Skybrid winch was showing a real lack of power. At the time this winch was the club's only functional winch so when a rebuilt Oldsmobile 455 was found via ebay, it was decided to purchase this. This would be mostly a direct bolt-in swap, unlike the Chevy 454 engine whch would need some days of fabrication to engine mounts, exhausts, etc.
• The engine was collected from Leighton Buzzard by James Hunneman. The owner had had the engine rebuilt for use in a jet boat, the work had been done by a small company (Al's Glides) who built transmissions and engines for Drag cars , and was familiar with these Oldsmobile Engines.Th engine had had a rebore, and new pistons. New camshaft, gaskets, seals, etc. The engine was supplied with a heavy marine flywheel, a normal distributor (ie not with a built in HEI system)
• Block casting number 396021F (note: The block casting number is found at the front top of the block just behind the water pump, to the right of the oil pressure sender unit. On this engine its 396021F - This casting number was used between 1968 and 1972 and is the most common big block type for the Olds 455 engine)
• Head casting numbers - above middle exhaust port. 394548. Letter "C" on front of the side. C '67 - '69 425 80 394548 A/C '68 H/O's. Toro's and 442's got big 455 valves. Rumoured to flow the best of all BB heads. (JH note: I checked with the owner, because these dates were before the introduction of unleaded petrol - he said he seemed to remember paying for hardened valve seats to be installed)
• This engine was installed into the Skybrid winch in April 2019. The HEI distributor, pulleys, alternator bracket, alternator and exhaust manifolds from the original engine were used to install this new engine.
• The new engine came with a cast aluminium Edelbrock inlet manifold.
• New stainless steel exhaust manifolds were obtained and installed in Summer 2019
• There is a slight issue with the bolt pattern on the crankshaft end. Apparently there's an early style spacing of the holes, and a later style. Typically, the crank in the new engine has a different spacing to the (definitely later spec) crank & flexplate from the original engine. JH obtained a new early spec flexplate. But one hole on this didn't line up correctly either - hence had to be adjusted to allow all 6 bolts to be fitted.

Spare parts

• As of June 2020:One spare starter motor on the shelf. Another is fitted to the spare Pontiac engine - same as Oldsmobile one.
• Purchased Summer 2020 - imported direct from Summit Racing - complete engine gasket set. Spare exhaust manifold gaskets.
• Oil filters are available from local parts factors (e.g Motorists Discount Centre, Newbury 01635 42015) But don't confuse the people by asking for a filter for an Olds 455 - simply ask for the filter by part number: Fram (the manufacturer's name) PH25 (the part number)(about £11) or alternative, Fram PH3429. (Other info I have suggests the following makes/model numbers of filters will work: AC PF45, Motorcraft FL-331, Purolator L20123)
• oil filter is becoming difficult to source locally - suggest EBay (CB 10/14)
• Air filter is Purolator A50091 (o/d 305 mm, i/d 249 mm, depth 88 mm) alt Fram CA326
• I have ordered parts from USautomotive (01234 273155). They're very helpful and have the parts in stock, or can get them quickly.
• American Autoparts (01737 780888) are also very helpful and have most parts in stock. Example of prices: Head gasket set £81, Distributor Cap £16, Rotor Arm £4, Condensor £4, Coil £28
• Rodley Motors 01274 688968 also very good.

Propane Gas Conversion

See the Propane Gas Conversion page for details