The early ('37-ish) Lasalle 322 had 6.25 cr (I believe) and produced 125hp. How can you best get just a bit more horses and anger from these early flathead 322's and 346's-without blowers or radical big $$$ mods? I am thinking increasing cr and looking to up hp to around 150-160hp-a little more would be even better Any thoughts and experiences would be good
Read this thread: http://www.jalopyjournal.com/forum/showthread.php?t=332457 And visit this site- www.flatcaddy.com Here's one you might like: http://www.jalopyjournal.com/forum/showthread.php?t=496866 Good Luck!
The cheapest way is probably a turbo. The tried and true methods will work to a degree on any old motor - better breathing, carefully milling the head to increase compression (but check to see if this has been done already). Make a twin-carb manifold, split the exhaust. A lot of work for 40 HP. Increasing the CR on a flathead makes it easy to decrease flow, so you have to be careful. And you can't just order a 3/4 race cam for one of those. So back to a turbo; probably a low-boost (motor is old), high flow (since you have over 300 c.i.) 'wet' turbo, or a carb hat and a 'dry' turbo. You can leave the motor stock and fiddle with the boost until you are happy. You would want to monitor the mixture and pressure carefully until you are sure you won't detonate the motor to death. I've never tried it myself, this is all second-hand info.
How fast do you want to go? Some years back I read a story about a guy who bought one new, a 1937 LaSalle sedan. He milled the heads .060, shimmed the valve springs put a cutout on the exhaust and made 107 MPH timed by stopwatch in 2 directions. Doesn't the Cadillac version come with 150 HP stock? You could take the LaSalle block and bore it to stock Caddy size, this allows you to use standard pistons which are usually cheaper. Do a 3 angle valve job. Get the cam reground. Install a bigger carb, dual exhaust or headers, hot ignition, and 2 steps a lot of guys overlook - have it balanced and shave some weight off the flywheel. This should give you 200HP or close to it at little expense and with little chance of blowing your motor sky high. To go much farther than that will increase your cost, and chance of blowing the motor, by a big amount.
Thanks guys. I have 2 x 322 Lasalle engines now, one a stock running '37 with stick shift trans I have just got from a running '37 Lasalle from Florida, the other a '41 322 Lasalle rebuilt engine only (20thou overbore, stock cam etc, just freshened)-yet to bolt on acessories and carbs/exhaust etc. Hope to eventually mate a 3 spd/od trans to this one I dont want to even consider blowers or turbos-not that radical or HP hungry. To put a figure on it, a modest 200hp would be just about right. Thus the cam grind, mild head mill, multi carb, header exhaust, valve job seems about right. Plan to build a non ford '30 3 window coupe (hopefully, when I can stike a deal with seller!!) and use '37 to go in there. The '41 engine...well I have a few other recipient car options when the time may come. That may be a while yet, to be honest Thanks to all, 38FLATTIE, Rusty and BFC. 38FLATTIE-I have been watching all your threads and posts with awe. Pretty radical stuff there. Have also visited flatcaddy regularly. Plan to get a few hop up parts from that site soonish. Great work. Will also follow up on your lumpy cam leads to soon-ish cheers, regards to all on this fantastic site Alan
Rusty, I think you are over-optomistic about getting 200 HP from the above mods, especially with a streetable cam. The military raised the compression 1 point, added dual exhaust, and 2x2 carbs. On a 135 HP engine, they got about 25 HP- and that was with the Caddy engine, that had 7:1 CR. The 322 Lasalle had 6.25:1 That would raise the HP from 125 to 150HP. A good cam, and better fuel may give you 175 HP, but I doubt much more without some port work. As for balancing the engine, they are pretty well balanced now-they were factory balanced. The flywheel is a harmonic balancing flywheel- if you lighten it much, you're going to have to balance the internals with it. These things are fun to drive, because the long stroke makes awesome torque! 3.375" bore, by 4.5" stroke. JMHO.
There has been some progress in cam and engine design since WW2. The last version of this engine was the 1947 Cadillac, 346 cu in 150 HP 7.25:1 compression. The LaSalle had the same engine with 1/8 smaller bore. These engines were very detuned for smoothness, silence, long life and lots of torque to move a heavy car. By comparison, if you took a 100HP Ford flathead and hopped it up to 133HP you would have a 1/3 increase. This would be considered a very mild hop up these days. If you did the same things to the Caddy, starting with 150HP a 1/3 increase would give you 200HP.
The last version came out in 1948, and had different lifters and cam followers, just FYI. The OP has a 125 HP Lasalle. It's bound to be fun, no matter the HP.
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