Hey, I'm looking to pick up a '48 Cadillac flathead motor to drop in my '40 Olds. I know absolutely nothing about flatties, can anyone educate me on what to look for? The guy said 2 of the pistons are stuck, does this mean turn and run the other way?
I know with my flathead Ford, I spend a lot of time looking for the money I put in it and all the horsepower it doesn't have, lol. I seriously don't know a thing about Caddy flatties. I think the rarity will be about equal to the difference between flathead Ford guys and modern engine guys. Good luck.
There's a lot of info on flat Cads on this forum if you do a search. Not sure what period you're looking to imitate; not sure if flat Cads actually had a period when they were the hot rodder's go-to powerplant. That's one heavy-*** engine with not many ponies and not much modern-day support. My friend rebuilt one for a '41 Caddy and it cost a mint to do so.
Last year for Cadillac flathead V-8 was 1948. First year for OHV V-8 for Cadillac and Oldsmobile was 1949. So I have no idea what you mean by "period hot rod, no overhead valves allowed."
Sorry, didn't mean to step on any toes. I just love the look and sound of the old flatheads. To restate, I guess this would be MY idea of an early hot rod, before the OHV motors came on the scene. I wasn't around back then so I'm probably wrong, just my idea of a cool car. I only remember growing up reading that the cheapest way to get more horsepower was to swap in a bigger motor. Granted, these things aren't known for big power, just wondered what someone would do at the time when they were looking at a six as opposed to a V-8? I'm just generally looking for some info on what to look for when buying a flathead motor...
You will spend $5000 at least to rebuild that Cad motor. ( paying for all the work). Do you have a 6 or 8 in your Olds? If you have a 6 you will maybe gain a bit of low end torque and lose top end. If it is a 8 you will about break even. IMHO
Do some reading in old Hot Rod,Rod & Custom,mags like those and you will find VERY FEW with flat Cads ,,,Too heavy and not enough HP...I was around back then too..
Contact AMBSN here on the Hamb. His Dad, Gary, runs a blown Caddy flathead at Bonneville, maybe he can offer some advise.
Of course I'm biased, but I think when you hear the name "Flattie" thrown about so frequently, most often the reference is to Ford flatheads, not Cadillac. They made some *****in' tank engines, but not so popular a**** the hot rodders. So, the first thing to look out for? Perhaps the name not being Cadillac.
Go ahead and ride that pony. I hope you have BIG saddle bags. Finding parts is one thing ,the other is paying for them.Like has been mentioned more than once if you are looking for interesting ,go with a Caddy. So period , more power ,and as I recall The Caddy OHV was and is a bad *** motor.. We can all color outside the box , but why?? JMO Good luck on your venture.
OK I guess I'm getting schooled here. Not what I wanted to hear, but I'll respect your opinions. I want cool but don't have an unlimited budget for it. What would you guys throw in a '40 Olds?
Almost hate to say it (because I'm a big flathead fan), but the go-to combination for low price, horsepower, and ease of installation is small block Chevy with automatic transmission.
You know the answer before you ask don't you? A SBC, I'm not a Chevy fan, but that is the cheapest route. If you are wanting to stay late 1940s, I would think Olds is the way to go. I built an Olds Rocket up one time. Or a Cad OHV. Olds in an Olds sounds cool to me, but so would a Cad in an Olds.
OHV Buick Fireball straight eight. Buick may have had the best 8 in row, at least for performance. A dual carb intake was an option on 41-42 or there abouts. Olds had a straight eight until 48, Pontiac till 54. Both the Olds and the Pontiacs were flatheads. Since there is little hop up for those engines may benefit from , port matching, homemade multi carb intakes, homemade headers, lightweight flywheels, and custom ground camshafts. IMHO the average hot rodder will find all that work...a little too period correct. Then there is the OLDS 6s A Chevy or GMC stovebolt is a viable period option with aftermarket support. Lastly is the OHV 303 Rocket and Cad engines, that were a mainstay of hot rodding in the late 40s early 50s.
You might contact povertyflats here on the HAMB. He finds, buys and sells vintage engines and usually has some pretty cool 50s V-8s around.
You want a flathead with some punch?........Latch onto a Hudson Hornet 308 flathead 6 with the dual carbs. Those Hudson's really performed on NASCAR circuits in the early '50s.......even beating the Olds V8s more than a few times, as I recall. Yeah, it's a little different.......but it IS a flathead WITH performance. And, it will fit in your Olds! Ray
Nothin wrong with a flat cad and yes parts are available and honestly not any more than a big block however it doesn't matter what people say do what YOU want I am a bit biased as I am involved pretty heavily with flatcaddys I set a land speed record with one last year at bonneville actually our team has 7 speed records with the flatcad here is a pic of my dragster I'm working on and we will be doing a build thread soon on the engine it will be in a working mans budget trust me I don't have big funds either speed parts are available you just gotta look a little further than the sbc The second pic is of the flatcad bonneville engine although it's very exotic and expensive it sure is pretty to look at Posted using the Full Custom H.A.M.B. App!
Cool thing about Cad flatheads is exhaust manifolds on top of engine. Good potential for freaky headers/zoomies out the hood ! Flatheads are notorious for overheating (at least in original beaters), so cracked blocks are pretty common. Good news is they are beefy so welding cracks usually works.. I have had many flatheads through my early hot rod years and still run a stock flattie in my '51 Shoebox. However, no way would I spend the bucks to pump one up. Water pumps aren't $14 at Pep Boys or Sears anymore! I think Olds in an Olds is best move! They were good enough for Gene Adams and Stone-Woods-Cook and you can still get an Engle cam. Doesn't get much more traditional than that!
I've got a SBF in a Ford.....................but if I had it to do over it would be a W-motor with a 700R4 behind it.
to I think he means, if your car had a six, not a V8, and you wanted more power, what would you have been likely to look toward to improve the situation..........
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