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MG MGB GT V8 Factory Originals Technical - Olds Jet Star V8

I have been offered an engine from a 1963 Oldsmobile Jet Star , similar to the Buick 215 V8. I know that the heads have a different
bolt pattern and angle. I am having difficulty finding info on compression ratio, etc
Can any one help?
Thanks Mike
Mike Cook

Try this-

http://lotus.www.50megs.com/V8articles.htm

Phil
Phil

also try
http://216.239.53.100/search?q=cache:-mW_o8nUnuwC:my.inil.com/~dlbrown/ofeng.htm+oldsmobile+jetstar+aluminum+v8+1963&hl=en&ie=UTF-8

HTH
jake
jake

Mike, the Olds Jet Fire 215 was a turbo charged engine yielding 215 hp. Odds are that the turbo is poop. The compression ratio is 10.5 or 11.0 to 1, the turbo was limited to about 4psi boost I believe. Olds got around detonation with a 50/50 mixture of alcohol and distilled water injected upon boost. Side draft Rochester ala Corvair turbo. The exhaust manifolds are unique as is the intake. Good luck, many parts difficult to source. Free is a good price, and there are Olds folks out there that would love to have the mill.
Cheers.
Curtis

Mike, If it's the Jet Fire (I'm not familiar with a Jet Star) it is indeed the turbo motor and is a rare piece. The heads are unique to that engine and have about the same chamber volume as the Buick heads. It is an excellent candidate for forced induction, as it has 6 head bolts per cylinder, and with a .040" mill job, composition gaskets, and low compression Buick pistons (still readily available) gives 8.5:1 or better compression. The rod bolts use 12 point nuts (aircraft style) and there are a few other refinements. That with a modern blower makes a potent package. (ask me how I know!) You may even be able to get a nice price out of the turbo, intake and manifolds although that's just a guess, I've never tried to sell mine. With free flowing exhaust and a 2" SU I got 6-7lbs boost from the stock turbo, but that was also with a custom 8-4-1 exhaust header system.
Jim Blackwood

Jim,
I have a Jetfire engine minus the intake stuff sitting on the floor of my shop. The block also has fatter main bearing webs and caps than any BOP or Rover 3.5 than I've seen.
David

sorry the last link didnt work, its actually http://www.442.com/oldsfaq/ofeng.htm#Engines 1949 - 1964

the info there is the following:

Engine Performance
Comp. Horse-
Year Series CID Ratio power Torque Induction
1949 88 303 7.5-1 135@3600 253@1800 2 bbl
1950 88 303 7.5-1 135@3600 253@1800 2 bbl
1951 88 303 7.5-1 135@3600 253@1800 2 bbl
1952 88 303 7.5-1 160@3600 265@2000 4 bbl
Super 88 303 7.5-1 160@3600 265@2000 4 bbl
1953 88 303 8.0-1 165@3600 275@2200 4 bbl
1954 88 324 8.25-1 170@4000 295@2000 4 bbl
Super 88 324 8.25-1 185@4000 300@2000 4 bbl
1955 88 324 8.5-1 185@4000 320@2000 4 bbl
Super 88/98 324 8.5-1 202@4000 332@2400 4 bbl
1956 88 324 9.25-1 230@4400 340@2400 4 bbl
Super 88/98 324 9.25-1 240@4400 350@2800 4 bbl
1957 All 371 9.25-1 277@4400 400@2800 4 bbl
Tri-power 371 9.25-1 312@4600 415@2800 3 2bbls
1958 All 371 10.0-1 265@4400 390@2400 2 bbl
All 371 10.0-1 305@4600 410@2800 4 bbl
Tri-power 371 10.0-1 312@4600 415@2800 3 2bbls
1959 88 371 9.75-1 270@4600 390@2400 4 bbl
Super 88/98 394 9.75-1 315@4600 435@2800 4 bbl
1960 88 371 8.75-1 240@4600 375@2400 4 bbl
Super 88/98 394 9.75-1 315@4600 435@2800 4 bbl
1961 88 394 8.75-1 250@4200 405@2400 4 bbl
Super 88/98 394 10.0-1 325@4600 435@2800 4 bbl
F-85 215 8.75-1 155@4800 210@3200 2 bbl
F-85 215 10.25-1 185@4800 230@3200 4 bbl
1962 D88 394 10.25-1 280@4200 430@2400 4 bbl
Super 88/98 394 10.25-1 330@4600 440@2800 4 bbl
Super 88/98 394 10.5-1 345@4800 440@3200 4 bbl
F-85 215 8.75-1 155@4800 210@3200 2 bbl
F-85 215 10.25-1 185@4800 230@3200 4 bbl
F-85 215 10.25-1 215@4600 300@3200 Turbo(1bbl)
1963 D88/S88/98 Identical to 1962
F-85 Identical to 1962
1964 Jetstar I 394 10.5-1 345@4800 440@3200 4 bbl
Dynamic 88 394 10.25-1 280@4400 430@2400 see Note 1
Starfire 394 10.5-1 345@4800 440@3200 4 bbl
S88/98 394 10.25-1 330@4600 440@2800 4 bbl


jake

So the question is: does this engine you're being offered have an aluminum block or turbo.

I'm not certain exactly what was changed in the Jet-Fire, as mine was built by Lemley Racing and I've yet to pull the pan. However I have had the heads off so I've gotten a good look at the top end. The combustion chamber is unique to these heads, as there is a lug or boss inside the chamber which is missing in the 4bbl heads as I recall. It's no surprise the block is unique as well as beefier webs would have been considered necessary back in those early days before it was discovered that turbos weren't that hard on the block or crank. Still the info gives me a comfortable feeling with an Eaton sitting atop the motor.
David, do the mains use 12 point fasteners as well?
BTW, back in those days Olds was conservative with their Hp figures as compared to the other corporate divisions, and in addition the turbo motor was intended to produce a higher actual level of performance than the 4bb Buick version. Dyno tests tended to confirm that result, although in those days there was still enough variation between engines coming off the line that the main consideration was often what day of the week it was built.

Jim
Jim Blackwood

David, do the mains use 12 point fasteners as well?


Jim,
Sorry to respond so late. I've been painting my car. Yes, my Olds engine has 12-point main bolts.
David

This thread was discussed between 24/11/2002 and 11/12/2002

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