Previous Thread
Next Thread
Print Thread
Forged Crank Question... #1393342
02/25/13 01:12 PM
02/25/13 01:12 PM
Joined: May 2011
Posts: 41
Sherwood Park, Alberta, Canada
Lighthorseman Offline OP
member
Lighthorseman  Offline OP
member

Joined: May 2011
Posts: 41
Sherwood Park, Alberta, Canada

Since I am doing an auto to 4 speed swap, I am looking for a forged crank, since I've heard that a cast crank just isn't going to cut it. I have a line on what a guy "says" is a forged 440 crank, but the numbers don't seem to make any sense.

The number on the crank is apparently 1988 761.

Can anyone help me out? (My appologies for cross-forum posting...)

Thanks!
- Steve -

Re: Forged Crank Question... [Re: Lighthorseman] #1393343
02/25/13 01:26 PM
02/25/13 01:26 PM
Joined: Oct 2007
Posts: 733
New York
R/T1968R/T Offline
super stock
R/T1968R/T  Offline
super stock

Joined: Oct 2007
Posts: 733
New York
Take a look at the archives....this should help http://www.moparts.org/Tech/Archive/bb/50.html

Re: Forged Crank Question... [Re: Lighthorseman] #1393344
02/26/13 01:16 AM
02/26/13 01:16 AM
Joined: Aug 2003
Posts: 43,007
Bend,OR USA
C
Cab_Burge Offline
I Win
Cab_Burge  Offline
I Win
C

Joined: Aug 2003
Posts: 43,007
Bend,OR USA
You need a 4 speed forged steel crankshaft, not a automatic forged steel crankshaft IHTHs


Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)
Re: Forged Crank Question... [Re: Cab_Burge] #1393345
02/26/13 01:25 AM
02/26/13 01:25 AM
Joined: May 2011
Posts: 41
Sherwood Park, Alberta, Canada
Lighthorseman Offline OP
member
Lighthorseman  Offline OP
member

Joined: May 2011
Posts: 41
Sherwood Park, Alberta, Canada
A 4-speed specific forged crank? IS there such a thing, or are you funnin' a newbie? I thought it was the pilot bearing that is needed for a 4-speed application.

Re: Forged Crank Question... [Re: Lighthorseman] #1393346
02/26/13 02:28 AM
02/26/13 02:28 AM
Joined: Jan 2011
Posts: 4,785
Utah and Alaska
astjp2 Offline
master
astjp2  Offline
master

Joined: Jan 2011
Posts: 4,785
Utah and Alaska
You need a hole to put it in...in the back of the crank, some auto cranks did not have it. Tim


1941 Taylorcraft
1968 Charger
1994 Wrangler
1998 Wrangler
2008 Kia Rio
2017 Jetta

I didn't do 4 years and 9 months of Graduate School to be called Mister!
Re: Forged Crank Question... [Re: Lighthorseman] #1393347
02/26/13 03:38 AM
02/26/13 03:38 AM
Joined: Mar 2003
Posts: 5,134
Las Vegas, NV
Tom_440 Offline
master
Tom_440  Offline
master

Joined: Mar 2003
Posts: 5,134
Las Vegas, NV
Quote:

A 4-speed specific forged crank? IS there such a thing, or are you funnin' a newbie? I thought it was the pilot bearing that is needed for a 4-speed application.




Maybe this helps?

http://www.moparts.org/Tech/Archive/clutch/1.html

Re: Forged Crank Question... [Re: Lighthorseman] #1393348
02/26/13 10:32 AM
02/26/13 10:32 AM
Joined: Mar 2007
Posts: 9,336
South-Central (Sebring), FL
Commando1 Offline
master
Commando1  Offline
master

Joined: Mar 2007
Posts: 9,336
South-Central (Sebring), FL
Quote:


I've heard that a cast crank just isn't going to cut it.



First of all, let's go back to square one when everybody else is running off in a 100 different directions like chickens with their heads cut off.
Your forged crank is going to cut it unless you're having someone build you a 600 hp engine that you're going to do 8k rpm test & tune runs on Friday nights.
Another case of a little knowledge is a dangerous thing.

Secondly, if you say "a cast crank just isn't going to cut it" because it won't accept a 4 speed, there's a simple work-a-round solution to that by machining off the the end of the tranny input shaft and using a special order bearing from NAPA or some other places.

Third, if you already have a forged crank, MOST likely it will accept a 4-speed. Simply look to see if there is a hole at the end of the crank. If not, see #2.

Finally if you have a forged crank with the hole, go to town with it.

The forged and the cast cranks each use different flywheels, btw.

Re: Forged Crank Question... [Re: Commando1] #1393349
02/26/13 11:15 AM
02/26/13 11:15 AM
Joined: Jan 2003
Posts: 74,907
U.S.S.A.
JohnRR Offline
I Win
JohnRR  Offline
I Win

Joined: Jan 2003
Posts: 74,907
U.S.S.A.
Quote:



Secondly, if you say "a cast crank just isn't going to cut it" because it won't accept a 4 speed, there's a simple work-a-round solution to that by machining off the the end of the tranny input shaft and using a special order bearing from NAPA or some other places.






SPECIAL ORDER ???

If a crank is not finished reamed there is a bearing that is used in a Dakota that can be used and it's not special order as far as I know. :shurggy:

How much of the input shaft needs to be TRIMMED is ona case by case basis , measure once cut twice ... or is it measure twice cut once ???


Re: Forged Crank Question... [Re: JohnRR] #1393350
02/26/13 01:01 PM
02/26/13 01:01 PM
Joined: Mar 2007
Posts: 9,336
South-Central (Sebring), FL
Commando1 Offline
master
Commando1  Offline
master

Joined: Mar 2007
Posts: 9,336
South-Central (Sebring), FL
Actually you're correct. I meant "special order" in the sense you probably won't be able to walk into NAPA and find one in stock on the shelf.

Re: Forged Crank Question... [Re: Commando1] #1393351
02/26/13 02:20 PM
02/26/13 02:20 PM
Joined: Feb 2003
Posts: 12,675
Columbia, CT
M
moper Offline
I Live Here
moper  Offline
I Live Here
M

Joined: Feb 2003
Posts: 12,675
Columbia, CT
I believe the NAPA adaptor pilot bushing is discontinued. Mainly because of the pilot bearing that JohnRR mentionned that works better and is only slightly more expensive.


Well, art is art, isn't it? Still, on the other hand, water is water! And east is east and west is west and if you take cranberries and stew them like applesauce they taste much more like prunes than rhubarb does. Now, uh... Now you tell me what you know.
Re: Forged Crank Question... [Re: Commando1] #1393352
02/26/13 04:31 PM
02/26/13 04:31 PM
Joined: Jan 2003
Posts: 74,907
U.S.S.A.
JohnRR Offline
I Win
JohnRR  Offline
I Win

Joined: Jan 2003
Posts: 74,907
U.S.S.A.
Quote:

Actually you're correct. I meant "special order" in the sense you probably won't be able to walk into NAPA and find one in stock on the shelf.




The unit for the Dakota should be an in stock item , the pilot bushing for a 1970 would have to be ordered more likely ?


Re: Forged Crank Question... [Re: JohnRR] #1393353
02/27/13 02:50 PM
02/27/13 02:50 PM
Joined: May 2011
Posts: 41
Sherwood Park, Alberta, Canada
Lighthorseman Offline OP
member
Lighthorseman  Offline OP
member

Joined: May 2011
Posts: 41
Sherwood Park, Alberta, Canada
Thanks for all the info, everyone! I have a 2843212 flywheel, which, I believe, is an 11 inch, 143 tooth unit. Someone mentioned it was "neutrally balanced", and someone else said that it is likely an internally balanced one.

Then, the crankshaft apparently "might" be a pre-1962 crank which is no good for going in anything post '62. Also, there is a possibility that it might be an "extended flange" unit, which wouldn't work either.

Holy smokes, am I ever confused. I'm going to go look at the thing today and see if the bolts match up 'twixt the crank and my flywheel. If I'm still not sure, I'll just get LOTS more pictures and ask for help.

Thanks to everyone up to this point!
- Steve -

Re: Forged Crank Question... [Re: Lighthorseman] #1393354
02/27/13 03:57 PM
02/27/13 03:57 PM
Joined: Jan 2003
Posts: 25,618
Rio Linda, CA
John_Kunkel Offline
Too Many Posts
John_Kunkel  Offline
Too Many Posts

Joined: Jan 2003
Posts: 25,618
Rio Linda, CA

The extended flange crank is easy to spot, it has 8 unthreaded holes...see pic below.

The 212 flywheel is for internal balance.

7605679-Earlyflange.jpg (47 downloads)






Powered by UBB.threads™ PHP Forum Software 7.7.1