Technical 3 or 5 main bearing crank for street / strip banger?

Now that I have retired, I'm pulling together information and cost for building an all motor 30's Ford 4 cylinder. I wan to build an engine that can run up to 5 grand rpm and put out close to 200 ft-lbs torque. The crankshaft seems to be one of the weak links in achieving this goal reliably. New cast 3 bearing cranks with counter weights are available; more rare are 5 bearing cranks with girdles to hold the 2 extra bearings. Cost for the crankshafts are approx $1,500 new cast 3 bearing vs $6,000 for 5 bearing crank and girdle systems.
Questions:
Can a 3 bearing new cast crank stand up to hill climbs, drag races and freeway speed road trips; run reliably at 5k rpm?
Is a 5 bearing system prudent insurance against grenading an expensive engine?
Does a crank girdle really hold the 2 extra bearings in position during abusive driving?
Thanks in advance for your recommendations.

 

If you havent read it already, get Jim Brierley's book. Tod Buttermore is casting new blocks now, and has patterns for a 5 bearing block. Crower and Moldex are two sources for a custom crank, and there are others. Search the monthly banger thread for some more info. I myself havent built one of these, just been reading and researching like you are doing. Where did you get the 5000 rpm number? Can you make it breathe at that speed?Good Luck.

 

Contact 530sandman here on the HAMB. A wealth of information on building a banger motor.

 

[QUOTE=" Where did you get the 5000 rpm number? Can you make it breathe at that speed?Good Luck.[/QUOTE]
See RK Designs dyno graph: http://modelaperformance.com/
An OHV conversion is part of the equation.

 

My take/opinion/experience:
If you have 5 main block/crank, you don't need girdle for what your asking.
NEW 3 main cranks (that are)available are not capable to withstand/do what you want. One's I'm familiar have B size mains and A size rod journals. Snap at #4 mostly every time, and this is not drilled for pressure. Drilled for pressure further weakens rod journals small as As. Full pressure oiling is the way, so FULL B size 3 and/or 5 main is the way.
I have a (NEW) drilled FULL sized C crank/Crower rods, inserts, B cam, etc,etc, in a warmed up B engine. I also just did break in of a hot B engine, with a Full sized C crank drilled full pressure (Bonneville USED original) Ford crank. 6 crank flange chev bolts (can be up to 8 ) , Babbitt rods/mains, hot cam, etc,etc...

Both with crank balancers, complete balanced assemblies. Which do you think will last longer spinning at 5K ?
Exactly, you never know ! Both built pretty strong, but both built with 3 mains , to start with.
So, start with 5 mains and full pressure and thousands of $ worth other top of line stuff and I'd put my $ on this.
The old adage....how fast do you want to go, how much $ do you have/want to spend....still holds true..lol

These are PRIMITIVE engines in design/tech. How long will one hold together at 5K , is anyone's guess.

You might be asking...'what's the difference between a warmed up B and a hot B.....answer; MONEY !

 

If you want to drag race or hill climb be sure the rules will let you run a later block.

Charlie Stephens

 

[QUOTE="
These are PRIMITIVE engines in design/tech. How long will one hold together at 5K , is anyone's guess.

You might be asking...'what's the difference between a warmed up B and a hot B.....answer; MONEY ![/QUOTE]

Thanks for the good info. I can't go faster than my wallet. I may consider building strong bottom with valves in block and lower my expectations.

 

wonder about the 40/41 truck block or what is used in the 9N-2N-8N Ford tractors.....I know my tractor is running that many bearings....

 

Unless you're totally stuck on Fords, check out the posts on here of the 5 main Mopar bangers. Might reach your goal.
Can find the links right now. Search Rich Fox.

 

How many cubic inches? I seem to remember that there weren't very many.

Charlie Stephens

 

ok my two cents worth. I was wondering the same thing about a model A ,otor that redlines like 3500 rpm. Runs great, got t-5 behind it but took 10 minutes and a good tail wind to get up to 55,60mph. Started reading the Mercruiser articles on here and took the plunge. This thing runs great in my 1930 tudor sedan. Rated at 120 hp right off the bat its got a few more speed goodies on it. My next move is a/c. Cant wait but now I believe Ill have the beans to cruise with it. Also I used the stock radiator and it works real good with a electric fan. Anyway Im happy with it and it was waycheaper than just the machine work on the old bangger.

 

Why the electric fan?

Charlie Stephens

 

Come on you two, the guy is asking about a 3 vs. 5 bearing crank, not Mercruiser swaps.

 

See RK Designs dyno graph: http://modelaperformance.com/
An OHV conversion is part of the equation.[/QUOTE]
Interesting link, thanks for posting that. I know Ron Kelly has a good reputation, but I would think for $8000 plus, he damn well ought to put the head and valve cover on it and run it in. That one I didnt understand, especially since you hear of so many people who dont do it a lot having head gasket install problems. Good Luck

 

George Miller made his own OHV head and built a 5 Main setup.Might get some ideas.
http://fordbarn.com/forum/showthread.php?t=179683&highlight=george+miller

John

 

My opinion (and I routinely put my money where my opinion is ) run 3. Mine's an eight not a four banger, just make 'em count. I didn't skimp on the mains on this blower motor, they cost about $500 and another $500 to CNC fit them. It's tough, see that bowtie bar stool quivering in fear under the counter?

 

Thanks for the good info. I can't go faster than my wallet. I may consider building strong bottom with valves in block and lower my expectations.[/QUOTE]

Hey ThosD,
Don't despair. I'd make darn good and sure that 4 bangers is what you want and in your blood, before going at an engine real hard right from the get go. Wish I had it to do over again. Knowing what I now know, I'd have saved a ton and built even better than I have now.
I can't tell you why I'm like I am about 4 banger engines, except to tell that that's what I grew up with...flatheads and Model As. I guess that I'm a uncomplicated guy and that flathead in simple machinery. Right now, I'm stuck on '32 B bangers and admit it !
I'd suggest that if you are determined to build a banger engine, learn how to get the BEST block that you can start with. Saves money from not having to do repairs/sleeves and can be 'improved' for power. I chose the B block , because Ford put internal oiling to mains/cam..pretty big deal. Only a few small mods to make full pressure filtered oiling then. Two major items that you can do with GOOD block is 4" bore and 1.75" intakes=more power. Stock exhaust valves do very well and that is a plus, eh ! These things you can do without breaking the bank. Before any mods, make sure that the block is good by CLEANING it out really good, and have it tested. Taking time building, saves money by you watching/finding the parts that you need to gather for eventual assembly. Knowing some old time tested 'tricks' of trade, also will pay off for a powerful build...without breaking your wallet all at one time. For instance, knowing that early 50s Chrysler lifters...have a HUGE foot that will accommodate any cam grind/fit is a plus. And, by cleaning up worn lifter bores, they fit nicely. Shop for a good automotive machinist or buddy who can do valve fitting, etc. YOU can also do a little porting/polishing and pocket relief (all breathing improvements).
Just examples of many little things that you can do to make a block perform much stronger than stock, while you chase after needed build stuff. However, don't scrimp on things, like bronze cam gear and steel crank gear (Dan McEachern gears).
One last thing. If you do not know of a guy named Jim Brierley (Bonneville record holder with B bangers), you should look into buying a book that he wrote about 3/4 yrs ago, named 4 Bangers and Me. Very down to earth stuff that if used will help avoid costly mistakes and help you improve your knowledge on the subject.

 

2X on the Brierley book : suggest buying 2 copies & wear the 1st one out with reading BEFORE you start building anything(& you'll have the 2nd one for reference for later! LOL!!)

 

If you really want 5 mains, have you considered this?: http://www.donovanengines.com/donovan-model-d-block/

 

Beautiful for the street but I bet you couldn't get it by the inspectors for use on hill climbs or TROG etc.

Charlie Stephens

 

True, unless the inspector has no familiarity with Model A motors. Still, it must be nice to get an intake port for each cylinder and five mains. Way too rich for my blood but I'd love to see a thread on building one.

 

The inspector might miss it but the guy that was smart enough to come in second place would sure point it out to them.

Charlie Stephens

 

(He's got that right!)
But honestly, everyone will be all over it! (It will not pass for a F.A.S.T. Race!) T.R.O.G. "Forget about it!"
If you want to race, you better stick to an A or a B block!
Find a good Diamond block and if you plan on a 4 port OHV do a 5 main for sure! If you stick with a flathead, a good C crank with real good C/B rods like (Crower) will be your best bet! The rods will be the most expensive parts. (STAY THE HELL AWAY FROM SCAT CRAP, CHINA 3 MAINS!!!!!) they only have (A) sized rod journals and WILL BREAK!!!! They can legally say made in U.S.A. only because they machine them here in the U.S. and that takes more than half the time of making them!
I'f you go with a 5 main then the rods are a little cheaper cause the blanks won't have to be as thick and you can have 2" rod journals with narrower rods.
I say spend that money, go 5 main billet crank! It's your money so do what you want with it!
Then if you want more power you can put anything on top of that block/lower end! (GO CROWER)
Joe

 

So I would like to throw this out. (1) Considering Tod's new blocks and the 5 main "B" block option, Moldex or Crower custom crank and associated costs of fitting the 2 together, what are we looking at in total costs? (2) Compare to the cost of finding a good B block and crank plus machining.

What do you guys think?

 

Tod's blocks are already changing the face of "A-Dom", even if they aren't released yet : "Why spend a 'Gazillion' dollars to make 70yr old parts into something that's now being made 'new', & with the 'good' oiling system already 'on board', & for a lot less time & money , especially when Tod's blocks(suggest 5-main & 'B' mains!!) should be 'out' in the next few months? Save on the block & spend for a new 5-main "B" crank that's been drilled for rod oiling & H-beam rods; in the long run it'll be a lot cheaper!

 

My experience with 3 main cranks leads me to believe that you better gear to stay under 4 grand cause that is where they break, usually at #4. In 2010 the car ran 82 at Antique Nationals. I back figured that to be 3780 or there about. Crank did not break but dampener and flywheel came loose and crank, which is a stroker,on a B, bent like a pretzel. According to Joe Castillo. It was out .010 or more across the rear main! He tweaked it all back to where a 10/10 grind straightened it and brought it back into register.I believe the B crank is more malleable and can take this abuse.
5 main cranks are probably the way to go if you are a "dial 800" builder and can throw a lot of money at it! Most completion rules state 4 cylinder 1934 or earlier. I run a 1930 A block. As usual the big money people will force the true hot rodder out if allowed to!

 

One more comment on my engine. When my grandson ran 82 we had 3.83's in the rear and he kept on accelerating and has no idea what RPM's he was turning but he said it had more when he shut down so he musta been turning over 4 when the shit hit the crank !
In this hobby, you cannot take just one person's experience but must inquire as much as you can.

A question, what is the difference in running a Tod's block over a Mercury or a Donovan? I mean as far as rules are concerned as to age or type.

Oh, where have all the Buda cranks gone?

So, we have the guy on a limited budget toiling away under his shade tree, filing and Hammearring to get her his hopped up A trying time compete and along comes the dial "dial 1 800" guy with the fat wallet and knurf's the poor guy out so he says "f" it and stays home.

Maybe the classes should be based on engines cost !

 

I just don't get it. Over 10k to achieve 150 hp using no pre war parts.
May as well buy a Pinto motor for a couple of hundred, get OHC with it too. (Exaggerated point I admit)
The whole point for me is to use original parts. If 4 pre war cylinders won't get you what you need just have to fit more cylinders.
My two pennies.

But keep with the 4 in my opinion. Cars were born for 4 cylinders.


Sent from my iPad using The H.A.M.B. mobile app

 

I agree with: (go with the 5 main). But honestly, (In my opinion) There is no such thing as a "dial 800" banger build! You will be on the phone for sure cause no matter what kinda shop you have, you will still need someone to make the Crank and cam, pistons,rings, rods and stuff like that! The most important part of the engine build is knowing what you have and what you need in (exact) size and profile of what you are buying. If you build an (off the shelf parts) The engine will either be a turd or will break before you have a chance to do your second head torque! I myself run a 3 main C/B crank I know for a fact, I've been way over 5k rpm! It's the details of the build/builder! drilling the crank in the right areas and chamfering the holes and polishing the inside of the drilled crank. Make sure to use a real good oil pump! The list goes on and on! I am building a 5 main Diamond B engine cause I know I'm on borrowed time with my engines lower end! By next time this year, I will be the guy driving my Banger to the race, swap gears in the QC rear, (RACE) and swap the gears back, then drive it back home! I won't care if the race is thousands of miles away! I'm not "Rich" Believe me! (I wish I went 5 main from the start!)
I'm just doing what I love!
While trying to be cheap and cut corners, (I've spent a lot of money on experience!)
Once again, good luck! I hope to race you all someday, even you sbc guys! lol (if there is any of you reading this?)
Joe

 

A LOT CHEAPER...ho,ho, ho !
But , you are correct regarding Tod's new block creations. Especially the 5x5 versions in alum and/or cast iron. If you can wait for one of those and can afford the 'other' necessaries, a strong banger will indeed be possible. How many Rrrrrs it will be able to withstand , is yet to be seen. But , one heck of a lot more than your average 3 main block, IMO.

Bill is also correct however, in that he says will Tod's blocks be accepted for hill climbs, etc ? And just WHO is it that makes these rules/that decision anyway ? Rules that allow a guy to cut up a monster CHEV V8 head or whatever, put it on an aftermarket 'diamond' block (is that legal to run in hillclimbs, etc, as is not original Ford block?) with hand made internals of 5 cam and 5 main bearings. Just what the hell is STOCK and acceptable about that against an original 1928 thru 1932 Ford smelted cast iron block ????? Soo, is my '32 B Russian block then illegal to run hillclimbs ?
Didn't the 'old timers' say...you run what you brought ? As long as it is a four banger not over so many cubes, why not let them participate ?
Bill also says ...match them up in class , according to $$$$$$ spent. Maybe not so bad of an idea, eh ? I've seen four bangers with so much 'equipment' on/in and around them....as to say...how do you know that there IS an original Ford four banger in there or not ? At Bonneville, etc...I am told that 'they' can tear down a guys engine to verify what's what. Is that also a standard at hill climbs ?
Anyone know ? Anyone have the hill climb rules/regs to share here ??

Anyway, I digress.....
As for me, I have not been fortunate enough (read: $/time)to be able to participate. However, accepted or not, I am determined to make one of Tod's 5x5 run like the devil from holly water.
Maybe I'll just have to offer a challenge to like minded banger guy 'outlaws'...LOL

BTW...anyone know how to fasten a four barrel/fuel injected blower to a banger , ha !