cubic inches vs. liters...big or small block?
12-16-2008, 09:33 AM
#1
Melting Slicks
Thread Starter
cubic inches vs. liters...big or small block?
I'll be the first to admit I'm not really mechanically savy... but can anyone explain the C6 engines to me? There are different liter sizes and I'm used to cubic inches... 5.7 ltr = 350cid (I think). Are the C6 Corvette small blocks or big blocks? Thanks!
12-16-2008, 09:44 AM
#3
Moderator
Member Since: Dec 2002
Location: Lakewood Ranch, FL
Posts: 40,070
Received 3,579 Likes
on
1,619 Posts
350 ci is slightly more than 5.7L (5.736L) and 5.7L is slightly less than 350 ci (347.835 ci).
12-16-2008, 09:50 AM
#4
Melting Slicks
Member Since: Oct 2005
Location: Goleta California
Posts: 2,516
Likes: 0
Received 2 Likes
on
2 Posts
Small block versus bib block has been defined as the distance between cylinder walls. You can google it and find a number of write ups on it. I believe wikipedia has a nice short discussion. The engines in the vette are all small blocks including the 427 CI (7.0 liter engine) To convert 1 cubic in equals 2.54^3 cm's.
12-16-2008, 10:41 AM
#8
Safety Car
1974 was the last year for a big block Corvette.
It's based on physical size of the block. CI isn't the determining factor.
You can have a 396 big blocks and a 427 small block, where the 427 is smaller in physical exterior size than the 396. But the internal displacement is larger.
Larger displacement, smaller exterior size is ideal for power to wt ratio.
That's why 74 was the last year for an iron big block. A big block 454 vette sounds cool, but it's a heavy slug. Now, do that displacement in an aluminum small block and you've got something.
It's based on physical size of the block. CI isn't the determining factor.
You can have a 396 big blocks and a 427 small block, where the 427 is smaller in physical exterior size than the 396. But the internal displacement is larger.
Larger displacement, smaller exterior size is ideal for power to wt ratio.
That's why 74 was the last year for an iron big block. A big block 454 vette sounds cool, but it's a heavy slug. Now, do that displacement in an aluminum small block and you've got something.
12-16-2008, 10:50 AM
#11
Race Director
Member Since: Sep 2007
Location: Peoria/Phoenix AZ
Posts: 16,555
Received 2,061 Likes
on
1,505 Posts
C6 of Year Finalist (performance mods) 2019
1 liter = 61 cubic inchs
12-16-2008, 11:30 AM
#13
Small block versus bib block has been defined as the distance between cylinder walls. You can google it and find a number of write ups on it. I believe wikipedia has a nice short discussion. The engines in the vette are all small blocks including the 427 CI (7.0 liter engine) To convert 1 cubic in equals 2.54^3 cm's.
12-16-2008, 12:51 PM
#14
Instructor
Member Since: May 2007
Posts: 174
Likes: 0
Received 0 Likes
on
0 Posts
Old Fashioned
Remember when you got 1/2 gallons instead of liters. When they changed to liters you got less and paid the same. When I use a ruler it still has 12 inches. And when I go 80 mph in my Vette I know exactly how fast I am going. You know all this BS has me scared! When are we going to switch over to the Euro??? Don't laugh since we don't really know where obanna came from.
12-16-2008, 12:53 PM
#15
Melting Slicks
The original gen 1 small block came in 265, 283, 302, 305, 307, 327, 350, and 400 cubic inch versions. The big block Mark IV was the only one used in Vettes. It came in 396, 402, 427 and 454 cubic inch versions. The current Chevy 502 and 572 crate motors are based on the Mark IV block. Only the 396 (1965 only), 427 and 454 were used in the Corvette.
All Corvette engines since '75 have been small blocks, regardless of displacement. And, of course, 1 liter = 61 cubic inches.
A bit of trivia: the original 302 used in the Camaro Z28 was essentially a 327 block with a 283 crank.
12-16-2008, 01:03 PM
#16
Racer
Member Since: Mar 2008
Location: Haughton LA
Posts: 252
Likes: 0
Received 0 Likes
on
0 Posts
Here's a free and very convenient (downloadable) conversion tool... Think of it as a gearhead's stocking stuffer...
http://joshmadison.com/article/convert-for-windows/
Happy Holidays!
http://joshmadison.com/article/convert-for-windows/
Happy Holidays!
12-16-2008, 02:30 PM
#19
1974 was the last year for a big block Corvette.
It's based on physical size of the block. CI isn't the determining factor.
You can have a 396 big blocks and a 427 small block, where the 427 is smaller in physical exterior size than the 396. But the internal displacement is larger.
Larger displacement, smaller exterior size is ideal for power to wt ratio.
That's why 74 was the last year for an iron big block. A big block 454 vette sounds cool, but it's a heavy slug. Now, do that displacement in an aluminum small block and you've got something.
It's based on physical size of the block. CI isn't the determining factor.
You can have a 396 big blocks and a 427 small block, where the 427 is smaller in physical exterior size than the 396. But the internal displacement is larger.
Larger displacement, smaller exterior size is ideal for power to wt ratio.
That's why 74 was the last year for an iron big block. A big block 454 vette sounds cool, but it's a heavy slug. Now, do that displacement in an aluminum small block and you've got something.
The big block was the only way to get large displacement before precision casting techniques were developed in the 1950s. You had to have enough metal in the design to allow for shifting of sand cores used in the casting process. Precision casting technique reduced the amount of core shift, and allowed less metal to be used between the bores. Thus the bore center to center dimension could be reduced, and the small block was born. Closer bore spacing meant a smaller block, smaller heads, narrower crank journals, etc. All of those things improve performance while saving weight.
Of course precision casting technique can be applied to the big block too. This allows gargantuan displacements such as the current 502 and 572 cubic inch crate motors.
12-16-2008, 02:42 PM
#20
Melting Slicks
Member Since: Oct 2005
Location: Goleta California
Posts: 2,516
Likes: 0
Received 2 Likes
on
2 Posts
A dressed 427 LS7 weighs 344 pounds. A dressed 427 big block weighed just over 900 pounds.
The big block was the only way to get large displacement before precision casting techniques were developed in the 1950s. You had to have enough metal in the design to allow for shifting of sand cores used in the casting process. Precision casting technique reduced the amount of core shift, and allowed less metal to be used between the bores. Thus the bore center to center dimension could be reduced, and the small block was born. Closer bore spacing meant a smaller block, smaller heads, narrower crank journals, etc. All of those things improve performance while saving weight.
Of course precision casting technique can be applied to the big block too. This allows gargantuan displacements such as the current 502 and 572 cubic inch crate motors.
The big block was the only way to get large displacement before precision casting techniques were developed in the 1950s. You had to have enough metal in the design to allow for shifting of sand cores used in the casting process. Precision casting technique reduced the amount of core shift, and allowed less metal to be used between the bores. Thus the bore center to center dimension could be reduced, and the small block was born. Closer bore spacing meant a smaller block, smaller heads, narrower crank journals, etc. All of those things improve performance while saving weight.
Of course precision casting technique can be applied to the big block too. This allows gargantuan displacements such as the current 502 and 572 cubic inch crate motors.
"Precision casting technique reduced the amount of core shift, and allowed less metal to be used between the bores. "