Cost of rebuild a flathead

sanborn

sanborn

Senior Member
A young friend needs to totally rebuild his 50 flathead. It will be a stock rebuild. I estimated it to cost about $1500-$1700 for parts and shop labor. Is this in the "ballpark"? Carb and ignition work would be extra.

The engine is running now but compression is very low(25-60 lbs.) and the usual tricks to get it up didn't work. The engine doesn't have enough power to pull up a steep hill.
 
I would say 15-17 is a good price I am having one rebuilt now...its costing more than that in calif....a good guage for price is ebay....I have seen them between 22-2995......on up....You may want to ad adjustable lifters.....and better forged pistons but not necessary...I went with new cast pistons a little better than Henry's....flatheads can put out some hp....and will beat a 327 if built right.....happy new year Gump
 
I think that $15 to $17 is low, sorry to say. I's say that you take what it costs to rebuild a Chevy Small Block and go at least 2 1/2 times as much, maybe 3. That is, if you want build in reliability and dependability. If you are going for any speed or dress up, all bets are off. Nostalgia is expensive.
 
The problem is this stuff is it is OLD. When you get into it, things crop up that you did not anticipate. Parts seem to be about twice what simular parts for a SBC would cost.

It takes me twice as long to assemble a flathead as it does a SBC.

Try to have someone who currectly works on Flatheads help you. You do not want to pay for the learning curve for a shop that is not familar with Flatheads.

Just my opinion.

Chris
 
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I think a lot of people go overboard when they rebuild a flathead. Since this is not an engine that will see a lot of miles, I usually put in new pistons(if there is a lot of slop) or rings only if fairly tight and new valve rings. That's about all I do to an engine. And I do all the work myself, except for the boring piston holes. Some people will tell you a rebuilt engine will need to be balance. That I believe is a big waste of money. I was talked into having one balanced and I could not tell any difference between it and one that was not balance.
 
My rebuilt 59A is sitting in the basement waiting for the car to return from the paint shop. I have over $5000 invested in the engine including the speed equipment and I still need carbs. Cost of the machine work alone was $1600. Everything in mine is new except for the Mercury 4" crank and the valve seats, which were OK. And I didn't skimp. I had a 6V electronic distributer with a 21A crab cap built especially for this car. The cost occasionally delayed parts purchase and extended the rebuild time frame but I wanted it done right. I could have gone to a SBC for a third of this cost but that ain't what I wanted in my '36 sedan.

This whole project was financed by selling my beloved Ferrari. Sometimes you gotta make hard choices.
 

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About 20 years ago,I had the machine shop at the foot of the hill I live on rebuild a 1941 100 horse engine, an 81T as I best remember.It cost me $700.I was horrified! In today's money,we would be looking at 3 grand,I think,although Obama says there is no inflation.Nowdays,I take the most outlandish price I can think of and square it.I'm usually still a little low on price.It is unbelievable what cost can run. James
 
IMG_0787.JPGIrregardless of the engine, for me, it is do it all the way, or don't do it. I recently had my flathead rebuilt. My rebuild consisted of:

Deluxe degrease
Dis-assemble shortblock
Bore cylinders
Crankshaft turn
Assemble shortblock
Grind valve seats
Re-size rods
R&R pistons
Balance (if you see the material taken off, it will convince you to do it next time)
New parts: main bearings, rod bearings, cam bearings, timing gears, oil pump, all new valves, valve keepers, valve springs, camshaft, pistons, rings, adjustable lifters, complete gasket set and paint.
Cost: $3,000.00 (intake, heads, carbs, etc. extra)
 
There seems to be much regional differences. If you do the tear-down and assembly yourself, you can pretty much cut the cost in half.
 
My 81A cost about $3500 with a balance. Isky 77-B and bored to 239 standard but otherwise all stock. My machinist knows flatheads and how to set up floating rod bearing clearances. He balked at doing non-adjustable lifters - more man hours to hand fit each one individually. Although I had to adjust them since I have smaller hands!

He said the balance helps not with power, but adds to longevity by reducing stress on the recip assembly. As was said, these aren't getting any younger and my engine may be original to the the car. It still had Ford script mushroom valves all the way around.
 
I also just had one built, bored with new pistons,cam and lifters was a bit over the $3000 mark as well. Pretty typical flathead build in the Indianapolis market.........
 
Speaking of balanceing. I just had this 276 that I am now building balanced. You cain't believe how far out this 50 merc crank was. Of course i'm useing 3 ring EGGE pistons, but there not that much lighter. Had to drill some big holes in the counter weights. I build a 276 last winter with a new Scat 4in. crank. That was so far out I thought would have to send it back. Balancing make a big differance. Walt
 
Just about 20 yrs ago, by accident, I found this old man who loved to rebuild flatheads, probably had been doing it for years and years, and still just loved doing it! I told him I need everything, motor and ****** with a 12v generator. He had several blocks, and all the other parts to build several complete engines. he built me a new rebuilt 100HP stock 59A with crab style distributor, 12v gen, Holley 94,and new rebuilt 39 transmission with clutch and all, running and ready to drop in, total cost $1200. Even 20 years ago I knew I got a super deal!
 
I had a 49 to 53 engine rebuilt five years ago. The cost was $3500.00. The next one I am thinking of having H and H do the work. They do them all the time and publish their prices and know what to look for. The freight will be an expense but I think It will be worth the money.
 
I agree with Russ/40. I started planning a rebuild 5-6 years ago. Shop for the right parts beforehand ,it will save you a some money.
 
If you add hard seats,new valves (one piece stainless),guides,springs,cam and heads flattened, block squared, balanced crank assy., I would think $2200/$2300. You do the assembly.
 
Great thread. I think the cost of rebuilding depends on what the original engine/box of parts were. The engine in the original question (50 Ford), Would be relitively inexpensive as everything in the engine is reusable. Valves, regrind. crank, regrind. Rods reusable as is. oil pump, reusable as is. Obviously anything defective is replaced. If and a big IF the rotating assy is original and only pistons are replaced, then I think Ballancing is a waste of money and I know of no shops in this country that balance their engines. This is a customers option. When I first went into the rebuilding business I used Patricks engine kits, they ran about $500 I charged 125 to bore .125". 80 bucks for a valve job. Then Assembly the engine. At that time I charges 500 dollars for my labor, which included porting and clearancing the heads for valve lift. Cam and lifters were extra.
Today we have over kill on what is done to these engines and the price to do them. One re builder once told me, when a Flathead came into his shop the cost automatically went up a thousand dollars, because they took too much time.
Now lets bust another myth, power output of a street Flathead won't exceed 150 HP We've dyno'd too many of them. The last 276 with L-100 8.5CR some port work and a PM-7 produced only 135 @ 4600, and this was not a cheep rebuild.
 
Too many variables... I have about 3500 in mine and I did EVERYTHING myself, including machining. I started with a complete runner in good shape that had been rebuilt in the 80's and seen very little miles since. But... .of course I couldn't leave well enough alone, and since there was a little bit of wear to the bores, I bored it again. Added old weiand heads/intake/fuel rail, chrome 97's, headers, etc...

Like Ron says above, it depends on what you start with and also how far you want to go.
 
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