flat head or not? need advice

[solidnoise]

ok. i got a 29 plymouth 4 door sedan.

factory equipped with a 4cylinder flatty.

Should rebuild it, but we did have it running and it will run/drive.

only problem is those stock flatheads are only toppin out maybe 40, especially being so old.

This simply WILL NOT do!

To keep it mopar, my pops and i were thinking of finding an old truck slant 6 mainly for dependability... but also it'll get me some more speed, without being wickedly fast. This is more a cruiser build.

But I kind of like the idea of using a flathead. I personally have no experience with them, this being my first. But i see more and more rods keeping the touch with them. i can see beefing up an 8 cylinder, or a 6 for more conservative room, but i wasn't sure if there were anything i can really do with a 4cyl flathead.

i was told i could port it, but that was about all.

so i'm here asking some more experienced flathead guys what i might possibly be able to do to keep a decent flathead and still get more speed out of it so i could actually run around not trying to push her at 30/35 mph.

To anybody with advice... thanks.

and if its a total waste of time to mess with a flat 4 then don't be afraid to tell me.

also... i'm looking at a budget so keep in mind i'm not trying to look for any other flatheads so i'd most likely be using what i have available.

thanks

 

[railroad]

I cannot see the flat four doing enough to enjoy crusing. Try to find an old hemi if you are a good mechanic. If not, I would look for a 318, 340 or 360.
I would not turn down a 383 or 440. Just go with what you can find a good deal on and make it your own.

good luck,

 

[dmw56]

You could probably get a flathead 6 go 65 mph with the right gearing. My Stude with a 6 could but was better at about 55.

 

[Daman]

To keep it plymouth I'd go with a 225 slant. They made them for years from the early 60's up into the 80's with electronic ignition. and they lasted forever. Pick one up and do a farmer rebuild (gaskets, rings and bearings)

 

[solidnoise]

To keep it plymouth I'd go with a 225 slant. They made them for years from the early 60's up into the 80's with electronic ignition. and they lasted forever. Pick one up and do a farmer rebuild (gaskets, rings and bearings)

yeah.... if i'm not keeping the flat four i was going to look for a slant.

seems like the obvious choice is to upgrade which means you guys will be seeing pics this year of another build everyone can follow.

 

[BigIrish]

I think those early mopar 4s were only 25 hp, which make sense with your 40mph top speed. Even if you do manage to get 40hp out of it with porting, carb, etc, that only puts you in stock Model A territory which isn't much better.

You would spend an awful lot of $$ building it up to get any power out of it and then you'd have to worry about reliability.

 

[R Pope]

The '29 Pilgrim was basically a '28 Chrysler model 52, which meant that it could cruise at 52 MPH all day long. It's a much better engine than any Model A ever had. I have one that is a factory rebuild, still has hone marks on the walls. It runs very smooth, and starts instantly. I think it would be a good oldtimey hot rod engine with a shaved head and dual carbs. Might have to use Model A carbs for parts availability though. I guess it depends on how much of a tinkerer you are. A "leanin' tower of power" might be better for you, certainly more trouble-free and turn-key reliable.

 

[PhilJohnson]

also... i'm looking at a budget so keep in mind i'm not trying to look for any other flatheads so i'd most likely be using what i have available.

thanks

I have seen quite a few decent running flatheads of various makes with transmissions for under 300 bucks. I have ran a few, a straight 8 288 cubic inch Packard, 218 Chrysler six, and a 161 Willys six. Out of them all I liked the 218 Chrysler. It was good on gas (30 mpg in a 53 Cranbrook) and could keep up with traffic just fine.

 

[Unkl Ian]

The Bonneville guys have recently discovered the mopar 4 cyl.
They will make some power, if you lean on them hard enough.
Lots of custom made parts required, NOT worth it for the street.
The mopar flathead 6 is only slightly better.

Check the length on a 6 cyl, to see if it will fit.
A V8 might be best.

 

[michaels]

Go for the slant 6, lots of good info on them at slantsix .org Cheap and easy to work on, not as much power as a v8 but 150 hp would be easy and thats alot more that the 25hp four. Headers, dual manifolds, a variety of intakes, cams all available, have fun with it whatever you do.

 

[goose-em]

I read an article recently but can't remember which mag it was in, maybe KKD or Hot Rod Deluxe.

The article was on a guy who builds those old flathead mopar engines and they put out some power. Probably not real cheap but it wouldn't hurt to talk to him for a little insight.