Making a Model A block 5 mains

George, I love seeing your projects, keep up the good work. Don't be too afraid of using the V8 crank. IH used V8 cranks in their 4-cylinder Scouts for a number of years with no problems.

Good Luck

 

Apart from going out of business

 

IH used V8 cranks in their 4-cylinder Scouts for a number of years with no problems.

Not according to a good friend with an International dealership since the '50's Rod were the same though.

<hr style="color: rgb(229, 229, 229); background-color: rgb(229, 229, 229);" size="1"> Apart from going out of business

Not yet Bluto--but according to him the crap that their making now, indicates that they sure are trying to.

Herb

 

JGMagoo,

Did your friend mention any more information about which Hercules he used the 5 main crankshaft from?

 

Probably meant:

Seriously though, this is a very cool project. Using the V8 crank in the 'banger block reminds me of the T guys using Wills-St. Claire V8 cranks in their blocks.

-Dave

 

Some people just start with Dodge Bros. engines that came with 5 mains. To easy I guess.

 

Its not that the rules for the hill climb say you have to use a Model A block or a B block or a G28 block. By the way I had a 26 and a 27 dodge.

 

Much !

Not to steal the thread AGAIN, but what are the DB 4 engines to keep an eye out for?

 

I dont see any reason and 90 Deg crank wont work.. Firing order should be 1432 ...very neat stuf guys... never knew any of this stuf on flat heads.. its before my time..Glad to see people still love these old cars... they are all a work of art...

 

OK, let me see if I can 'splain this. V8 cranks, since Henry, have had the throws 90 degrees apart. Four cylinders can have either a 1243 or a 1342 firing order to have a power impulse every 180 degrees of rotation. Now lets look at th V8 crank, from the front of the engine. Conventional rotation is clockwise. Lets say that one crankpin is at top dead center, on the firing stroke- call that #1 cylinder pin. you say the next cylinder to fire should be #4. If the crank makes 180 deg rotation #4 will be opposite #1. Next on your firing order is #3, which should be after another 180 deg.- but wait- that's #1's pin--see why four cylinder cranks are made with two throws 180 from the other two?

OK, let's say we skip the 180 stuff. Top pin (firing) is #1, next pin up will be #4, and it fires (after only 90 deg) next #3 (again after only 90 deg) and then #4 (you guess how many degrees this time) Now we are back at #1, but it's on it's exhaust stroke now, so can't fire. Ditto #4 #3 and #2 and back to #1 which can now fire again--so you have an engine that goes bang-bang-bang-bang in one turn, and then coasts for the next full turn. Not so good-----

OK, now lets number the pins differently. #1 still top and firing. Next up #2, then #3 and then#4. Number 1 fires, then the crank has to turn 270 deg to get to #4 which fires, then crank turns another 270 deg to #3 which fires (now we have gone 1 1/2 turns) 270 more deg to #2 (2 1/4 turns total) BUT 90 degrees ago we passed #1 the second time so it had to fire (unless this is some strange 6 stroke) when we passed it. Next one ready to fire(because it's been two rev since last time ) is #4----- again because of two turns.

This gives you a firing INTERVAL of 270-270-90-180- Very lumpy, and probably impossible to balance.

You can number the pins any way you like, and come up with any firing order, and this is as good as it's going to get.


The Wills-St Claire had a flat crank (like a four cylinder) because it was a 90 degree V8, as were the Leland Lincolns (the pre Henry ones) Modern V8's are not.


Herb Kephart

 

just a thought.. wouldn't you want to have the crank before you set up those extra main webs? or am I missing something?

 

The '28 "Fast Four" is easy to spot as it has the same intake and exhaust port arrangement as a Ford and the distributer through the head also like a Ford. If you want to convert to OHV the '26-'28 Standard four has only one intake port on the opposite side as the exhaust and the distributer is mounted on an aux shaft outboard the block. Hill climb guys are very one way for discriminating against Dodge and Plymouth engines. I may take this up with the ACLU. Pretty sure I have a case.