Thread: Flathead Newbee Needing Direction!

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Hey I do not actually know how much the setup in that '34 cost, but figure if it has the conversion to a C4 trans that is at least $1500 (about what a 700R4 would cost after some modification) that is about the same as a SBC setup but I am not sure you can adapt a flathead to a GMC transmission so you might have to include the C4 conversion in the cost.

C4 kit $1250
triple intake $260 (8BA)
Isky cam $244
Stromberg97 $150 each x 2 or 3 ??????
Heads $440 (Offenhauser as in Picture)
Pistons $275 (three ring)
Rings $120
Bearings $ 95 (8BA)
Oil Pump $128
4" crank $896 (new, $500 from me)
water pumps $ 90 each, need two
distributor $400 (8BA) Mallory dual point
chop flywheel$100?
Headers $130
Hot Coil $ 30
Main Supports$ 40
Adj. lifters $140
Valve guides $ 56 (set of 16)
valves $160 (stainless, optional)
springs $ 60 (single)
etc. ........ $_?????_______________
Est. Total $5454

Machining block, boring etc. $ 12/hole x 8 = $96
Porting & Relieving??????? Guess $500

Block ???????????????????????????????????????

That is a rough estimated of cost using prices from the Speedway catalog. Stainless valves are an option and I forgot the hardened valve seats or a three angle valve job. The point is that things are a little more expensive for the flathead than for a SBC rebuild which I think can be done nicely for about $1500 so that is some idea of the costs but the main problem is still finding a good block!

Don Shillady
Retired Scientist/teen rodder

thats about twice as much as i got in my sbc 350 right now. i mean it is alot but if you build it over time it can be done. i took me a bout a year and a half to buy all the bullet sutff for my sbc anyway. All the crome and bullet parts cost me more than building the long block did ! I would say 2 to 3 times more, and im still changing parts. so i figure if ! and i mean IF i find a good block i think i will try it, hey if i can't at least im sure i could get my money back.

It sounds as if you are determined to try to build a flathead so go to it. The point of the cost analysis above is that after all that expense to get somewhere between 200 and 250 HP, it can be compared to an inexpensive 350 SBC which gets 270 to 300 HP. Of course you can spend more on the SBC but nostalgia is the operative effect here and would be fun if only it were easier to find a good flathead block. One thing that might be worth planning on is to change over to hardened valve seats since the flatheads were build for leaded gas. Here is a link to a car/engine based on a flathead. The pictures are interesting because they show the reliefs ground into the block between the valves and the cylinders, that is a rodding trick, not the stock surface of the block.

http://www.34hotrod.com/HotRod/page7.htm

Don Shillady
Retired Scientist/teen rodder

Anytime you build an engine outside the normal sbc or sbf area, you are going to spend more. I could have built 3 Chevy small blocks for what I have in the 394 Olds in my '39 Dodge, but the wow factor makes it worth it.

I only mentioned the cost of building a flathead so you go into it with your eyes open. Also, finding a suitable core to begin with is tough.

Good luck.


Don

My impression was the 8BA blocks were better. With the 8BA the bellhousing can be adapted to many transmission choices. Peace

That is a good point about adaptability to other transmissions AND it may be easier to find an 8BA block. My brain is sort of frozen with the old formula of adding a '39 3-speed transmission to get a floor shift and a synchromesh set of gears, but actually that trans is pretty weak so if you are using a C4 or some sort of sturdier manual trans, the 8BA may indeed be a better choice. Actually folks still seem to be able to find useful flathead blocks somehow although even the Speedway catalog alludes to many with cracks and offers a kit to pressure test the block. Back when I was still hoping to get a good block I bought a '39 3-speed as rebuilt for $300 from a restorer which was a pretty good deal but even a slightly modified flathead can mess up a Ford trans if you wind it up in low gear and then hit a bump, so yes another modern trans might be a good idea.

Don Shillady
Retired Scientist/teen rodder

I guess what Don and Don are trying to say is that this quest for a flathead is frustrating as well as expen$ive. Most flatheads went to support the manufacture of cannons and bombs for both the Korean and Viet Nam wars, if that gives you a better pespective on the age of these engines. I built my share and raced them in the late '50s and early '60s - you could build a 'full race' 3/8 x 3/8 engine for way less than a thousand dollars. A good used block was, tops, $50. When I say 3/8 x 3/8 means that a '49 - '53 4" Merc crank was offset ground an 1/8" and '46 - '48 full floating bearing connecting rods used and the block was bored to 3 3/8" for a total of 296ci. A lot more than the .030 - .040 bore suggested. My favorite block was to bore to 3 5/16+.030 x 4" which was 283ci - which I used to dust off the similar size Chebbies.

Ford flatheads ran/run HOT because of the siamesed middle exhaust - 2 cylinders pushing hot gasses out 1 hole. Even an aftermarket port splitter had minimal effect on heat. Almost all flatheads have center exhaust port cracks - which are repairable with lot$ of money. And yes, I prefer the '49 - '53 blocks for the weight and bell housing advantage for different trans.

So with all these "good" words of advice, go for it.

Oh, by the way, this below is the best kind of flathead!!

Good break down Don, for those interested. I expect about $5000 (+$1000 or so). I would love to go under budget, but that rarely happens. Think of this way, If you end up putting $10,000 or so into a Hot Rod project; it still beats the heck out of any new car. And what kind of new car can you get for $10,000. No car payment and build it at your own pace, a new car loan takes 5 years to pay off and you pay about double the car's initial cost and it ends up being worth about 1/4th of what you end up paying for it.
My daily driver is a HP '68 Barracuda Fastback, my Street Rod will add to my rotation; nothing new that I can afford strikes my fancy.

Peace

Dave That is one great looking flattie. Is that a Pepco blower?

Booty-full ARDUN!

Don Shillady
Retired Scientist/teen rodder

Originally Posted by chevy 37

Dave That is one great looking flattie. Is that a Pepco blower?

Not a clue - most blowers for flatties were SCOT - but this doesn't look right for one of them.

I went thru a bunch of my show photos a while back, mostly prints, not digital, and have quite a few of flatheads - must be a sub-conscious thingie . These 2 were just from Rhinebeck this year

That looks like a '27 Ford with a V8-60 HP since there are only 17 studs, still very interesting.

Don Shillady
Retired Scientist/teen rodder

Don Your right on that 60Hp engine but I wonder why someone would put in in a vehicle besides the midget race cars that used them. They only had 94 bls. of torque. Even a old coupe that weigh maybe 2200 lbs, would"t go very fast with that engine.

Chevy37, I guess folks did not pay much attention to the (lack of) torque and the engines were cheap and they could get chrome goodies for the 60 HP. Still my next door neighbor in the '50s had a '40 Ford sedan with a 60 HP and he said he drove it in second gear a lot of the time and that is saying something because I think the standard rear ratio for the 60 HP cars was 4.11 or 4.44. I know of one guy locally with a T who has a 60 HP with similar goodies on it and he said hills can be a problem, but it looks neat! Historically I guess it was an attempt to go for more mpg, but for a full size 1940 sedan a 60 HP engine is hopelessly underpowered. I used to work with a guy who was on the track crew for a 60 HP midget and they had not won a race in three years and they were tired of losing so they bored and sleeved the 60 HP block for the 3 1/16" bigger block pistons. He lapped the field, steaming all the way, and was disqualified in the after-race inspection, but he said it was worth it just to see the checkered flag!

Don Shillady
Retired Scientist/teen rodder

Wish I could have seen the faces of the racers when he lapped them. Just the thought brings a smile to my face: