I was wondering with all these nice aftermarket performance parts for a flattie, how much hp can one make, without a blower, and still be daily driven. Ive been considering one but a buddy says only about 150 hp is going to be streetable. Also who, if anyone makes the best aftermarket flathead blocks. thanks
on the blocks I *think* that flathead jack is the only one that was working on a reproduction and they were going to be big $$ items... were supposed to be available some time soon. http://www.flatheadjack.com/hotrodengine/hotrodengine1.html finding a good block can be tough but cracked ones can be repaired.
and I have to believe that more than 150 is possible streetable. the later mercs were rated at 125 from the factory and with a mild cam, headers and some better ignition / induction you should be able to pick up more than 25hp. just find a merc 4" crank to go with your crack-free block although this is a good question!
I love flatheads... but they're not designed for horsepower 150 in a flatty is pumping it- 100 hp in stock form is fine I have edmunds heads, a weiand tri carb and reds headers on mine- I used to daily drive it. But now I dont need to drive as much. I think the key for me keeping my flatty from the machine shop is constant oil changes. theres lots of little differences that you need to pay attention to if you end up buying your first flatty... For example. My buddy bought a shoebox, didnt know jack about flatheads, put a new rad cap on and it overheated like a mofo. I ended up buying the car from him and discovered the 16 pound cap. they need a #4 cap and run a non pressurized system... changeing the cap back to #4 pounder ended the overheating problem. theres lots of wives tails about flatheads... and lots of neat tricks. If you buy one and run one run it because its a work of art and appreciate it... not to blow your buddys doors off. Tuck
You can get 150HP out of 'em & remain streetable. But why not bolt a blower on? Mark Kirby is also doing aftermarket blocks. Do a search in the archives - more info than you can possibly read on flattys...
there are always French blocks available,,, that is if they ever sorted out all the legal ******** they were going through ? anyone know?
I wail on mine. The ol Peter Beater goes pretty good. Unknown cam, Fenton 2x2 intake, Offy 425 heads, adjustable lifters, zoomies and a 5 speed with 4.10 gears in a Banjo get the job done. I'm really suprised the rearend has held together thus far.
Here is ONE thread about Flathead Building; http://www.jalopyjournal.com/forum/showthread.php?t=23305 It starts slow; but believe me, it has LOTS of GOOD information! Keep reading!
Halibrand cornered the market on those "French" blocks. Last I checked you can order one on their web site $$$$$$$!!!. Dunno how long for shipping. I'v been through four flatties and only one had a cracked block. It was a 59AB. Got rid of it quick. I seem to come across 8BA's pretty often, and have 3 squirreled away. Your best bet is to take your time and turn over a bunch of rocks especially with old dudes. That's where I got my motors and speed equipment. It's usually cheaper than the re-pops. But if you wanna build HP. Well I hopes you gots lotsa cash. P.S. Get the block magnafluxed as soon as you tear er down, that way you know she's good or not and you can proceed.
At one time, not to long ago I was also under the impression that the old V8 was nothing more than a cool looking piece of history and if you wanted to even keep up with traffic you needed a later motor. After putting together the 40 coupe for my dad. Just like the one he drove in the mid 50s, I was pleasantly surprised by the power even a fairly mild flathead makes. People that tell you there water boiling underpowered junk are the guys that never got it right or never tried. On blocks, theres still lots of good ones out there. I just picked up two the other day for free and one iv checked out looks like a good/crack free one. Dont be scared, they're a little more work and money, but its well worth it.
It is real easy to get 150-170 out of a 258 (Ford crank) or 170-190 out of a 276 (Merc crank) and be very streetable and not spend a whole lot of money either. Good magnafluxed and Sonic'ed block Full degreasing and cleaning at a shop Mol***es bath for block and heads. Does what the shop misses deep down in the water jackets. Nothing worse than a partially plugged block 3 5/16 bore .395 lift Schneider cam Refaced Johnsons or the new style clones EAB heads, about a .060 shave and cc matched chambers. Undercut behind valves, unshroud plugs and smooth transfer area transition Open up the exhaust ports 1.6" Chevy intake valves Mild block relief Block deck trued up and align bored. Be sure the machinest knows flatheads! Smooth intake runner in block, remove sharp curves Electronic ignition, I like Mopar conversions Offy 4bbl intake and adaptor Edelbrock 1406 carb, 600cfm, mechanical secondaries, set as required. Late 60's ~475-525 cfm Holleys off SBF's are a cheap alternative. Full rotating ***embly balance. The block porting and relief work can be done at home. Dual or 3 carb 94's are also good if you prefer that look and dont mind spending the time to tune them. Get a copy of Joe Abbins book "Blown Flathead" for the best, IMO, how-to on the block. The above at 276" will dyno a bit over 190 at 5500, sound *****in and run probably for 100K if you treat it right and do oil changes regularly. That means keeping it under 4500 95% of the time! Note I didnt mention full flow oil conversions above; do it if it makes you feel better.
Every day use?? Well here in Ohio everyday use means you drive it through the winter snow and salt. I installed an 8BA 53 flatty this past winter into my 37 coupe and I may not Drive it through the winter. But I can ***ure you this thing goes to work everyday a total of 80 miles @65-70 mph and makes every errand that requires a vehicle during non salty weather. I love it and will never go to a smallblock in a ford. Expensive?? if cost was a factor I wouldn't be in this hobby. 6000 miles since May. 18 mpg
Street Rodder finished their One Last Flathead in the January 2005 issue. They dyno'd the flathead Ron Ceridono had built. They got 182.2 hp and 222.5 ft-lb at 4300 rpm. That was with 2-97's on an Offenhauser Super Dual manifold on 276 cubes with an Isky Max 1 cam and Sharp heads. Best part from 3,000 to 4,800 rpm they averaged 169.8 hp and 230.8 ft-lb torque. Not bad and very streetable. The buildup was spread out over several issues: July 2004, August 2004, October 2004, November 2004 and January 2005. My own flathead will be similar. Not too much cam, 2-97's, good heads and built to drive daily on the street. Put that in a 2,500 lb or less car and you have a very streetable hot rod. Just do your homework and find someone who KNOWS how to build a flathead. Tuning once its built helps too.
Running a French flathead in my 31 PU. Got two 94's on it & a Mallory dual-point. I bought the flattie from a place in Texas who got them back from Halibrand when they went into bankruptacy. I bought a turn-key engine. $2350 plus shipping. It had a rebuild tag on the bell housing that said "1992". Also had 130 on it. Maybe HP? It was in French. It pulls hard to 4700 and carries 80# pressure on the road, 50 at idle. Also, you have to use 5-30 in it or trip the relief valve all the time. If any questions send me an e-mail ( jsfinley@comcast. net). Here's the site you can go to to contact them. http://www.webbed-toe.com/ Butch
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