crankshaft Q...

[hardtimes]

In you opinion/experience, what's the best NEW crankshaft purchase for the buck (Burlington/Scat/Other) ? Strength wise can engineer types explain forged vs cast as first choice.

[James Rogers]

I didn't know there was any new ones but the Burlington. The Scat is for Model T.
?

[George Miller]

Originally Posted by hardtimes

In you opinion/experience, what's the best NEW crankshaft purchase for the buck (Burlington/Scat/Other) ? Strength wise can engineer types explain forged vs cast as first choice.

I do not know, but I do not like the looks of the square edge on the Scat. between the rod throws. Maybe some can tell us why they are like that.To me it would have more resistance going through the oil and air. They both are real good material.

[Kurt in NJ]

the Burlington is set up for a stock rear "seal", the square looking scat is setup for some kind of rope or rubber seal ------the scat crank looked like it was made of powdered metal???(I saw one at Hershey), it has the smooth square sharp edged look of other things made of powdered metal,----perhaps I am wrong
the burlington crank looks like something Ford could have made.

To me it seems the scat is targeted more to the modified crowd, the burlington toward the stock crowd

[AL in NY]

Scat is now making both a Model A and a Model B counterweighted crankshaft.

http://www.scatcrankshafts.com/news/model_a-t.html

[Crazydaddyo]

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Originally Posted by Kurt in NJ

the scat crank looked like it was made of powdered metal??

Scat crank is Forged 4340. You can get it drilled for oil to the rods. The way they drill the cranks for oil is better then cross drilling a stock crank. they come with six threaded holes in the flywheels flange. I have an A and a T crank from them. First rate quality products.


.

[hardtimes]

Originally Posted by Crazydaddyo

Scat crank is Forged 4340. You can get it drilled for oil to the rods. The way they drill the cranks for oil is better then cross drilling a stock crank. they come with six threaded holes in the flywheels flange. I have an A and a T crank from them. First rate quality products.


.

Forged is good....better than Cast Iron crank
I ask because I'm running a new cast crank, one of a couple dozen made by an A/B banger guy known to me. Yesterday, I ran across a top notch machinist A/B engine builder who advised me that he is aware of one just like mine that snapped at #4 throw. If I'm looking for a new crank for another build, looking for input.

[Crazydaddyo]

Yes, forged is better then cast.
I've heard the aftermarket cast crank don't hold up to spirited driving.

.

[Kevin in NJ]

I went to the Scat crank web sight.

Their statement:

• Micro-polished for maximum bearing wear

Does not sound right, so they are trying to wear your bearings as fast as possible?


Ya I know what they are trying to say. Should be minimum bearing wear.

[zzlegend]

Originally Posted by Kevin in NJ

I went to the Scat crank web sight.

Their statement:

• Micro-polished for maximum bearing wear

Does not sound right, so they are trying to wear your bearings as fast as possible?


Ya I know what they are trying to say. Should be minimum bearing wear.

Maybe they should have said, "maximum bearing life".

[Chris in CT]

Hi Hardtimes, Thanks for the questions. Some backround: both the Burlington and the Scat crankshafts are made from 4340 forged and hardened steel. While the Burlington crankshaft is made in China, the Scat rough forging is made in India, with the end machining and grinding done here in the US. Burlington initially searched the USA for a company which would manufacture the crank domestically, and found no one who would do it - not for love, and not for money. Scat had the same problem with the forging process, but because it was equipped to make custom cranks for the competition and street rod trade, machining was not a problem for them.
The Burlington crank is a production product; the Scat crank is a custom product, and this difference accounts for the 4/500 dollar price difference.
Forged steel is stronger and more resilient than nodular cast iron. It is also considerably less brittle. Period. This would not be an issue if the rod pins and mains of the A crank were 2 1/2 inches instead of 1 1/2 - 1 5/8. A good beefy crank will work just fine in cast iron for a street-legal engine, but competitors will always go for 4340 or alloy steel billet cranks.
Both the Burlington and the Scat cranks are excellent products, and either one will serve your engine project very well. Both cranks are finish ground and balanced for maximum bearing life...etc. Happy Motoring!
Chris
-----------------------------------
www.burlingtoncrankshaft.com

[hardtimes]

Originally Posted by Chris in CT

Hi Hardtimes, Thanks for the questions. Some backround: both the Burlington and the Scat crankshafts are made from 4340 forged and hardened steel. While the Burlington crankshaft is made in China, the Scat rough forging is made in India, with the end machining and grinding done here in the US. Burlington initially searched the USA for a company which would manufacture the crank domestically, and found no one who would do it - not for love, and not for money. Scat had the same problem with the forging process, but because it was equipped to make custom cranks for the competition and street rod trade, machining was not a problem for them.
The Burlington crank is a production product; the Scat crank is a custom product, and this difference accounts for the 4/500 dollar price difference.
Forged steel is stronger and more resilient than nodular cast iron. It is also considerably less brittle. Period. This would not be an issue if the rod pins and mains of the A crank were 2 1/2 inches instead of 1 1/2 - 1 5/8. A good beefy crank will work just fine in cast iron for a street-legal engine, but competitors will always go for 4340 or alloy steel billet cranks.
Both the Burlington and the Scat cranks are excellent products, and either one will serve your engine project very well. Both cranks are finish ground and balanced for maximum bearing life...etc. Happy Motoring!
Chris
-----------------------------------
www.burlingtoncrankshaft.com

Hey Chris,
Thanks much! Very well stated information and fair to your competitor!
I like your business approach and style in explaining/answering my questions. You have also put me at ease over my use of this new B/C cast crank, as I'm not into racing it. Who knows under what circumstances that that same crank that I'm running...broke? I can't even imagine that happening with mine, as I had it balanced/checked by a crank shop. And, it was balanced with the other rotating components. As well, it sits on full pressured inserts and runs like a 'singer'
And , thanks for posting your website also, as I'm going to contact you with couple questions about purchasing a B/C type crank..full oil pressure.

I just read website and realized that you may not manufacture a B/C crank..bummer !

[zzlegend]

Hey Hardtimes. Let me know when you are going to assemble the motor. I would like to drop by and learn a few things.

[hardtimes]

Originally Posted by zzlegend

Hey Hardtimes. Let me know when you are going to assemble the motor. I would like to drop by and learn a few things.

I'll be talking with you !

[hardtimes]

Originally Posted by AL in NY

Scat is now making both a Model A and a Model B counterweighted crankshaft.

http://www.scatcrankshafts.com/news/model_a-t.html

Thanks for the website Al! And, just 'down the road' from me!
Yeah, it looks like scat has a variety to choose from, including for full pressure, whereas burlington has A / T! As I'm into B blocks, scat it is then !
FYI:
I just spoke with SCAT! Found out that their 7-B-4250H (oil drilled) has just gone up in price from website ad TO $1741...YIKES !
The other 'distrubing' news is that the rod journals are MODEL A SIZE, not the B size!
What do you guys think of the downsized rod journal size ? Aren't A rods smaller/inferior to B rods ??

[George Miller]

Originally Posted by hardtimes

Thanks for the website Al! And, just 'down the road' from me!
Yeah, it looks like scat has a variety to choose from, including for full pressure, whereas burlington has A / T! As I'm into B blocks, scat it is then !
FYI:
I just spoke with SCAT! Found out that their 7-B-4250H (oil drilled) has just gone up in price from website ad TO $1741...YIKES !
The other 'distrubing' news is that the rod journals are MODEL A SIZE, not the B size!
What do you guys think of the downsized rod journal size ? Aren't A rods smaller/inferior to B rods ??

When the crank breaks it is number 4 rod journal most of the time. I would rather have the big rod journals. All the power from 123 goes through number 4 rod journal. Ever time it fires the crank flex's, after while it breaks from fatigue. The more power the more it flex's.

[hardtimes]

Originally Posted by George Miller

When the crank breaks it is number 4 rod journal most of the time. I would rather have the big rod journals. All the power from 123 goes through number 4 rod journal. Ever time it fires the crank flex's, after while it breaks from fatigue. The more power the more it flex's.

George,
Thanks for that info!
Ok, so a natural follow up Q (from me) ...Would you say that Fords original B/C crank metalurgy/construction is equal to or BETTER than those made today, i.e.- cast iron and forged with small rod throws ?
Any other opinions on this question ?

[George Miller]

Originally Posted by hardtimes

George,
Thanks for that info!
Ok, so a natural follow up Q (from me) ...Would you say that Fords original B/C crank metalurgy/construction is equal to or BETTER than those made today, i.e.- cast iron and forged with small rod throws ?
Any other opinions on this question ?

Cast iron will not flex as much, but it is not as strong as 4340 forging. I would think the cast crank would break first. There are also lots of grades of cast iron, so you would need all the facts. Ford had the best steels of the time, I'm not sure if his cranks would be as strong as 4340. 4340 is a very strong steel, it is a little harder to machine, then 1040 or some other mild steels. A big radius is real important on the rod journals, and mains also.
We used a lot 4140 and 4340 when we made hydraulic cylinders.