70's Oldsmobile 350 into 3rd gen trans am
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Car: 1985 Trans Am
70's Oldsmobile 350 into 3rd gen trans am
Been looking around and can't find all the answers I need, so figured I'd just ask the experts as it were. I've ended up with a 1985 Trans Am w/305 tpi. for pretty much nothing. Needs work but doable. Engine isn't running and evidently had some issues when it was, so probably would need at least a rebuild after sitting 20 years. Automatic transmission probably needs changed out also as it was slipping when parked. From what I've researched and seen, most people question that effort going into that engine anyways, so...
My father has a 1970's Oldsmobile 350 engine that I can get for free. From the years they are called "big block 350s" although I don't think that term is completely accurate. Now normally I wouldn't bother messing with but this free engine had some pretty high end performance work done to it by prior owner and then never used (something like 3k in work 15 years ago, although we don't have details anymore). If looks manageable I can dig into the engine further to see what exactly is going on, but want to see if this endeavor is even worth it...
My father has a 1970's Oldsmobile 350 engine that I can get for free. From the years they are called "big block 350s" although I don't think that term is completely accurate. Now normally I wouldn't bother messing with but this free engine had some pretty high end performance work done to it by prior owner and then never used (something like 3k in work 15 years ago, although we don't have details anymore). If looks manageable I can dig into the engine further to see what exactly is going on, but want to see if this endeavor is even worth it...
- How big of a mess would I run into trying to make this work or what all needs considered?
- What transmission would I need to find to go with this that can match up to the car and engine (or at least there is adapters for)?
- From what I gather, engine mounts will be an issue. True, and if so, how to resolve?
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Re: 70's Oldsmobile 350 into 3rd gen trans am
It's an Olds motor. It's like Pontiac or Buick, DIFFERENT FROM Chevy; there ARE NO "big block" or "small block" of those. They're all the same. Same cyl bore spacing, same design, same weight, same same same. Same cam fits em all, same heads all bolt up, same same same same. Only thing that's different is the deck height. In the Olds, 307 350 & 403 are the lower deck height if memory serves; 400, 455, and several earlier smaller sizes are the tall version.
You'll find that it'll take more $$$$ to put that "free" motor into your car than it would take to BUY OUTRIGHT a whole Chevy small block and just drop it in. Not saying the Olds motor isn't "good"; not saying the Chevy is "better"; not not not not not not not not. Just saying, from point A (now) to point B (faster car), the Olds motor is FAR FROM the path of least resistance. The cheeeeeepest eeeeeeeziest fastest lowest risk eeeeeziest cheeeeeepest route DOES NOT go through that Olds thing.
Issues will be, engine mounts, accessory drives that will fit under your hood, transmission, crossmember, and exhaust that will fit your chassis.
I'd pass on the Olds motor. Save it for some POS that came with a 307. (Olds 307, that is)
You'll find that it'll take more $$$$ to put that "free" motor into your car than it would take to BUY OUTRIGHT a whole Chevy small block and just drop it in. Not saying the Olds motor isn't "good"; not saying the Chevy is "better"; not not not not not not not not. Just saying, from point A (now) to point B (faster car), the Olds motor is FAR FROM the path of least resistance. The cheeeeeepest eeeeeeeziest fastest lowest risk eeeeeziest cheeeeeepest route DOES NOT go through that Olds thing.
Issues will be, engine mounts, accessory drives that will fit under your hood, transmission, crossmember, and exhaust that will fit your chassis.
I'd pass on the Olds motor. Save it for some POS that came with a 307. (Olds 307, that is)
Last edited by sofakingdom; 08-18-2018 at 07:56 PM.
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Re: 70's Oldsmobile 350 into 3rd gen trans am
You would be way cheaper, easier, and all finding a good used 350 or even a 305 rather than entertaining the idea of that Olds engine. Rebuilding the 305 is a better idea than fooling with the Olds engine
#4
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Re: 70's Oldsmobile 350 into 3rd gen trans am
I wouldn't do this even if you had an unlimited budget. I had an acquaintance of mine in the 70s do this to a 68 Camaro with an Olds 425 (he said police interceptor engine), what a dog. My at the time factory stock 69 Ford Torino kicked that thing around like a red head stepchild. Get your self a good SBC and call it a day.
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Re: 70's Oldsmobile 350 into 3rd gen trans am
An engine sitting for awhile doesn't necessarily make it need a "rebuild". A "rebuild" doesn't cure things like corrosion in the radiator, gunk in the fuel system, disintegrating rubber parts in the brakes & suspension, etc.
Get the 305 to run and see what the car really needs. Again, that Olds motor isn't gonna cure any of that other stuff. You'll STILL have to deal with crap in the fuel tank, rusty brake cylinders, and all the rest of that kind of "sitting up" stuff. The "engine" doesn't deteriorate.
Get the 305 to run and see what the car really needs. Again, that Olds motor isn't gonna cure any of that other stuff. You'll STILL have to deal with crap in the fuel tank, rusty brake cylinders, and all the rest of that kind of "sitting up" stuff. The "engine" doesn't deteriorate.
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