Andy Tuttle
Full Member
Posts: 141
Member Nº: 299
|
 |
« on: October 10, 2010, 07:57:48 PM » |
|
Ok, since I am starting on the bottom end, and my crank is not worth salvaging, I am up to replace it. I am planning to retain the engine as a 327. I currently have a large journal crank. What is the difference between the large and small journal crank? IS there a performance advantage to going with one as opposed to the other? I know there is a difference between the large journal and small journal rods, but am not sure what that difference is. ANy words of wisdom?  |
|
|
|
|
Logged
|
It'll run again one day! In memory of Dad Tuttle 1933-1994 Giddy Up Go Daddy
|
|
|
|
C3 Corvette Forum 68 - 82
|
|
« on: October 10, 2010, 07:57:48 PM » |
|
|
|
|
|
|
Logged
|
|
|
|
vmiester
Full Member
Posts: 100
Member Nº: 33
|
|
« Reply #1 on: October 13, 2010, 07:13:52 PM » |
|
Hi Andy,Just read this post and your" dome no dome" post.The difference between the journal sizes is large journal:2.450 and small journal:2.300.Thats 150 thousanths or more than an 1/8 of an inch.I could probably spend an hour looking up bearing speeds and parsitic loss and other crap pertaining to large versus small journal cranks,but for street motor ,it makes very little difference.Just find another crank for that block and dump those high comp pistons and get it in the 10 to 11 range.You will be much happier. |
|
|
|
|
Logged
|
Rick
|
|
|
toobroketoretire
Newbie
Posts: 11
Member Nº: 9
|
|
« Reply #2 on: January 09, 2011, 03:19:41 AM » |
|
Ok, since I am starting on the bottom end, and my crank is not worth salvaging, I am up to replace it. I am planning to retain the engine as a 327. I currently have a large journal crank. What is the difference between the large and small journal crank? IS there a performance advantage to going with one as opposed to the other? I know there is a difference between the large journal and small journal rods, but am not sure what that difference is. ANy words of wisdom? The rod journal size was increased as the larger 350" was being tooled up for production. Although the friction increased slightly the difference is minimal and won't affect the engine's horsepower much. I would buy a stock 350" crank as they're so plentiful and plenty strong for street use. |
|
|
|
|
Logged
|
|
|
|
|
C3 Corvette Forum 68 - 82
|
|
« Reply #2 on: January 09, 2011, 03:19:41 AM » |
|
|
|
|
|
|
Logged
|
|
|
|
|
