How much better is a B block than an A?
- Thread starter brett4christ
- Start date
johnneilson
Well-known member
One detail about making new blocks, the audience of customers is very small, especially since the blocks cannot be used in Vintage racing.
John
John
Chris Haynes
Well-known member
Not everybody is a racer.
hardtimes
Well-known member
A three main A block set up to take a B crank with the bigger main bearing diameter would be a winner for me. The ultimate foundation for a rugged touring motor. Pressure to the mains would be nice but original A system would be OK. Just sayin'
For those here who may not be aware, YOU have just described the current projects being under-taken by TOD, a member here.
When you say...'ultimate' is 3 main B bottom , A block, that is not accurate tho.
Tod is making the A looking block with FIVE mains and that is the ultimate , IMV !
For those who care, and/or paying attn. to this type subject, Tod has already made a stock running Model A block (utube(?).
He has also made two experiment aluminum blocks modeled after the things that you want. First is an alum three main blk and the second is a five main alum version. Both are currently being worked.
At the same time, 5 main cast iron blk (tooling) being worked on.
Chuck Sea/Tac
Well-known member
Diesel requires more compression than gas, I’m pretty sure they used Babbitt as there was nothing else. By the way, the first compression fired engine was before 1900. I understand the concept your saying, but “Good” Babbitt will handle 7:1 and easily 6.1 what wipes out Babbitt is lugging under load and advanced timing.
johnneilson
Well-known member
Chris, exactly my point.
The market for an improved "B" block would be very limited by the fact that Vintage racing does not allow for aftermarket blocks. BTW, that market would benefit most as the output easily triples (and more) the original design power levels. Donovan I understand has sold the last one known as the "D" block. I do understand that there are a few around that can be bought, you have to look, and bring a stack of bills.
The "perceived" notions that "B" blocks are inferior to "A" blocks is IMHO an old wives tale. Sure, every production motor design/production can have flaws or weaknesses when power levels start to rise above design. This applies to lawnmower motors up to big diesel motors.
Babbitt bearing design goes back to the railroads, very large and heavy applications. Designed properly, alloyed, installed and lubricated properly it is very forgiving and will withstand much abuse. There is a well known person around here who ran a babbitt rotating assy in a "B" motor, OHV and Turbocharged on methanol at Bonneville. It is reputed to be his preparation for the races to just dust off the motor after removing it from storage and install into car.
John
Chris Haynes
Well-known member
I'd like to see it on a dyno.
hardtimes
Well-known member
Hey Bob,
Thanks, I don't know how to do this type procedure / reference .
Since that engine was made from a NEW A block and from USED spare model A parts, I'm thinking that it would/should make about 20 HP +/-, like Fords original ?
brett4christ
Senior Member
OK, a little more info requested...
I went back to snap a shot of the engine number stamping yesterday, but the pad on the side of the block was blank. I have since learned that, on B engines, this pad is blank and the B number is on the flywheel housing. My problem there is...I don't have the housing!
Now mind you, the oil pan stops at the rear main cap and has a knife-edge (not a rolled lip) that creates the seal. Pulling the pan, the crank is definitely counterweighted and the cam has a fuel pump lobe. I don't remember seeing a fuel pump boss or port through the side of the block.
Could this be a service replacement "A" block that came from Ford with a counterweighted crank and B cam? If so, would the crank be turned down to fit the A block, or would the block have larger journal bores? (Like a dummy, I didn't have my calipers to measure the rod journals!!)
Any ideas???
I went back to snap a shot of the engine number stamping yesterday, but the pad on the side of the block was blank. I have since learned that, on B engines, this pad is blank and the B number is on the flywheel housing. My problem there is...I don't have the housing!
Now mind you, the oil pan stops at the rear main cap and has a knife-edge (not a rolled lip) that creates the seal. Pulling the pan, the crank is definitely counterweighted and the cam has a fuel pump lobe. I don't remember seeing a fuel pump boss or port through the side of the block.
Could this be a service replacement "A" block that came from Ford with a counterweighted crank and B cam? If so, would the crank be turned down to fit the A block, or would the block have larger journal bores? (Like a dummy, I didn't have my calipers to measure the rod journals!!)
Any ideas???
brett4christ
Senior Member
Finally got a good look at all sides...found the fuel pump boss!
It's a Model B!
Going to get it home and try to make a silk purse from this sow's ear! Wish me luck!
It's a Model B!
Going to get it home and try to make a silk purse from this sow's ear! Wish me luck!
Terry NJ
Well-known member
Hey who says the A block is so great? They crack too! Go to any rebuilder and they'll tell you they have go trough 4-5 A blocks to get a good one.I think it's a combination age, temperature, clogged cooling systems, and too light iron in some places. The B blocks are even worse! However, The Russian blocks (GAZ) are free of this problem or so I'm told. I don't know about the German G-28 blocks. Some people say I'm wrong, but I believe metal "ages" even without external influences such as moisture, etc. This is especially true of castings.
Terry
Terry
brett4christ
Senior Member
Speaking of Russian/German blocks....How on earth would a common North Carolina grease monkey obtain one of these blocks? And I don't think I need to remind you all that NC grease monkeys don't maintain large bank accounts!!
johnneilson
Well-known member
Luck, it is the only true explanation.............
Being in the right place at the right time.
Don't write off the block you have, do the cleaning and inspection.
I have found good blocks in seemingly the worst condition caked with mud and grease that most people will walk by, or run.
J
Jim Brierley
Well-known member
John, The guy you speak of does more than just dust his engine off. First ran the turbo in '08, and every year after thru '13. In '13 it ran 167 MPH. The pan has been off twice, all OK both times, no new parts installed. This is on babbitt mains only, because of many drag racing years before, the pistons got tired so Ross forged pistons and Eubanks rods were installed. Before that babbitted B rods were used. 6200 RPM was max while drag racing, 6,000 on the Salt. This is on an early B block, 4" bore, no cracks ever. The worries now are the 'C' crank, so a 5-main crank and girdle are in process.
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Terry NJ
Well-known member
I don't know how or where one obtains a GAZ or G28 block. I know there are a few in the US, but your chances of finding one are slim to none. However, I mentioned it only because, first, both were made up until the 50s and second, the Russian and German engineers designed their casting cores with more "meat" in the critical areas. You will notice that most engines with a cracking problem, all crack in the same places so it's a known phenomena. You're not dealing with bad iron, your'e dealing with design flaws. Also I don't even know if a German or Russian block is better. I'm just repeating what I've heard.
Terry
Terry
johnneilson
Well-known member
I wonder where the Girdle came from.
All I can say is that I am sold on that combination, it held together when the drive shaft sheared pulling about 6200 revs on the dyno.
John
hardtimes
Well-known member
'wish me luck' !
If you are at all dependent on luck, in this type situation....you're most likely in for anything but !
There is no replacement for experience/skill/knowledge, etc. when going at this task. That's why most without these qualities , hire a good engine rebuilder....and communicate closely with that person for what you want.
Even the best here among us, have their detailed machine work done by expert machinist who do this for a living.
You might have heard this before, but if not....buy the two books that Jim B, a member here, has written on this specific subject(i.e.-engine building).
You/me anyone doesn't get that type of knowledge without going thru a LOT of trial/error...and heartache (read: money/failure)! Maybe cheating to learn from books and others, but I'm all in on that. See what I'm saying...excluding 'luck'.
Even some 'engine rebuilders' are unscrupulous sobs, so do your homework there also. If you were on the left coast, I would not hesitate to make a referral for excellent engine work and maybe who not to go to.
It is often said , about engine work wanted/needed...what is your intended use/purpose for the engine ? If you have to ask why this question, study up on the subject before spending a cent for parts and/or labor.
brett4christ
Senior Member
Thanks @hardtimes I know "luck" has very little to do with it!
I'm wanting a simple early pre-war hopped up Sedan that I'm not afraid to drive around town and maybe on some backroads. No speed demons here!
As far as acquiring knowledge, I've already ordered the Breirley book and I have both Les Andrews books. They will be my references going forward.
My hope is to piece together a sound engine from most of what I have. If it becomes a money hole, I'll part out the motor and move on with an off-topic powerplant.
And BTW, I'm on the right coast!
I'm wanting a simple early pre-war hopped up Sedan that I'm not afraid to drive around town and maybe on some backroads. No speed demons here!
As far as acquiring knowledge, I've already ordered the Breirley book and I have both Les Andrews books. They will be my references going forward.
My hope is to piece together a sound engine from most of what I have. If it becomes a money hole, I'll part out the motor and move on with an off-topic powerplant.
And BTW, I'm on the right coast!