10.5 and 11" flywheels?
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Melting Slicks
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10.5 and 11" flywheels?
I am swapping out my PG for a Muncie. 65 327.
If I want to run an 11" flywheel and clutch setup is it just a matter of changing the starter?
My starter now has the mounting bolts straight across from one another.
Does this dictate 153 tooth?
I bought a Lakewood scatter shield so I guess that would be fine for the 11" flywheel.
Thanks, Pete
If I want to run an 11" flywheel and clutch setup is it just a matter of changing the starter?
My starter now has the mounting bolts straight across from one another.
Does this dictate 153 tooth?
I bought a Lakewood scatter shield so I guess that would be fine for the 11" flywheel.
Thanks, Pete
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There is no such thing as a 10.5 or 11in flywheel.
Beginning with the very first Chevy V8 in 1955, there have only been two sizes of flywheels/flexplates:
1. Small, 12 3/4in diameter (frequently referred to as 13in) with 153 teeth.
2. Large, 14in diameter with 168 teeth.
The early flywheels were ONLY the large, 168 teeth version and MOST of them only had a bolt pattern for a 10in clutch (later replacement clutches are now about 10.5in). Some of the early 168 teeth flywheels, such as those for trucks had a bolt pattern for the 11in clutch.
In 1963, the smaller, 153 teeth flywheel was introduced and it ONLY accepted a 10.5 clutch.
The later, 168 teeth flywheels had a bolt pattern for the 11in clutch.
SOME replacement 168 teeth flywheels had a dual bolt pattern for either the 10.5 or 11in clutch.
ALLLLLLLLLLLLLLLLLLL V8 Chevy flywheels for engines with a 2-piece rear main seal have the same bolt pattern for the crankshaft. And ALL V8 flywheels, EXCEPT those for the SB400 and 454 BB, are neutral balance. The SB400 and 454 use the same size 168 teeth flywheels and accept the same 11in clutch, but they have an additional weight on the front side of the flywheel for engine balancing purposes. These 400/454 flywheels are commonly referred to as EXternal balance flywheels.
Here is a comparrison of the 168 teeth neutral and external balance flywheels.
Here is a comparrison of the 153 teeth and a 168 teeth flywheels.
Now, this throws one more fly into the ointment. Depending on which flywheel you choose, you must also have the correct corrosponding size bell housing.
Here is a comparrison of the small and large bell housings.
And then there is still one more issue, the starter. The small flywheel/bell housing requires a starter with the straight across bolt pattern. The large flywheel/bell housing requires a starter with a CAST IRON nose and a staggered bolt pattern. The starter with an alum nose and staggered bolt pattern WILL NOT FIT into the starter bulge of the big bell housing.
Hope this helps.
Tom Parsons
Beginning with the very first Chevy V8 in 1955, there have only been two sizes of flywheels/flexplates:
1. Small, 12 3/4in diameter (frequently referred to as 13in) with 153 teeth.
2. Large, 14in diameter with 168 teeth.
The early flywheels were ONLY the large, 168 teeth version and MOST of them only had a bolt pattern for a 10in clutch (later replacement clutches are now about 10.5in). Some of the early 168 teeth flywheels, such as those for trucks had a bolt pattern for the 11in clutch.
In 1963, the smaller, 153 teeth flywheel was introduced and it ONLY accepted a 10.5 clutch.
The later, 168 teeth flywheels had a bolt pattern for the 11in clutch.
SOME replacement 168 teeth flywheels had a dual bolt pattern for either the 10.5 or 11in clutch.
ALLLLLLLLLLLLLLLLLLL V8 Chevy flywheels for engines with a 2-piece rear main seal have the same bolt pattern for the crankshaft. And ALL V8 flywheels, EXCEPT those for the SB400 and 454 BB, are neutral balance. The SB400 and 454 use the same size 168 teeth flywheels and accept the same 11in clutch, but they have an additional weight on the front side of the flywheel for engine balancing purposes. These 400/454 flywheels are commonly referred to as EXternal balance flywheels.
Here is a comparrison of the 168 teeth neutral and external balance flywheels.
Here is a comparrison of the 153 teeth and a 168 teeth flywheels.
Now, this throws one more fly into the ointment. Depending on which flywheel you choose, you must also have the correct corrosponding size bell housing.
Here is a comparrison of the small and large bell housings.
And then there is still one more issue, the starter. The small flywheel/bell housing requires a starter with the straight across bolt pattern. The large flywheel/bell housing requires a starter with a CAST IRON nose and a staggered bolt pattern. The starter with an alum nose and staggered bolt pattern WILL NOT FIT into the starter bulge of the big bell housing.
Hope this helps.
Tom Parsons
Last edited by DZAUTO; 09-08-2010 at 02:52 PM.
#5
Melting Slicks
To use a 168 tooth flywheel (or flexplate), either the starter, or the starter's nose, will need to be changed.
If your old inline starter is good and you happen to have a staggered bolt pattern nose (perhaps cannibalized from a broken starter), you can swap the noses and you're fine. If it happens to be the aluminum nose, I believe that it can be used with the Lakewood scattershield,
If your old inline starter is good and you happen to have a staggered bolt pattern nose (perhaps cannibalized from a broken starter), you can swap the noses and you're fine. If it happens to be the aluminum nose, I believe that it can be used with the Lakewood scattershield,
#6
Melting Slicks
Also, if one wants to use a lighter 153 tooth flywheel for a 400 SBC or 454 BBC with external balance, McLeod makes them.
#7
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OK, this makes sense to me now.
Looks like my new Lakewood scattersheild has a "knock-out" provision for the smaller diameter flywheel.
Guess I will order the 153 Hay's billet flywheel and keep my starter.
Thanks a bunch guys.
Looks like my new Lakewood scattersheild has a "knock-out" provision for the smaller diameter flywheel.
Guess I will order the 153 Hay's billet flywheel and keep my starter.
Thanks a bunch guys.
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#10
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Two more items to complete the very thorough review from DZ.
If you're using the 153 tooth flywheel/bellhousing/starter on a big block (I am) you will have to use a '65 396 or L-88 starter brace.
The 153 tooth neutral balance flywheels come in two varieities. One is a 37 pounder with full metal thickness across the entire back face. It's the standard C2 small block flywheel. The other is a 16 pound nodular iron unit that has thin metal except for the friction face area. You used to be able to find those by the dozens in the used parts bins at the local speed shop, but not any more. I'm trying to find one for my 427. Makes 'em rev like a 302. God help me I don't feel like pulling the trans out after the car comes back from the body shop though.
If you're using the 153 tooth flywheel/bellhousing/starter on a big block (I am) you will have to use a '65 396 or L-88 starter brace.
The 153 tooth neutral balance flywheels come in two varieities. One is a 37 pounder with full metal thickness across the entire back face. It's the standard C2 small block flywheel. The other is a 16 pound nodular iron unit that has thin metal except for the friction face area. You used to be able to find those by the dozens in the used parts bins at the local speed shop, but not any more. I'm trying to find one for my 427. Makes 'em rev like a 302. God help me I don't feel like pulling the trans out after the car comes back from the body shop though.
#11
Le Mans Master
There is no such thing as a 10.5 or 11in flywheel.
Beginning with the very first Chevy V8 in 1955, there have only been two sizes of flywheels/flexplates:
1. Small, 12 3/4in diameter (frequently referred to as 13in) with 153 teeth.
2. Large, 14in diameter with 168 teeth.
The early flywheels were ONLY the large, 168 teeth version and MOST of them only had a bolt pattern for a 10in clutch (later replacement clutches are now about 10.5in). Some of the early 168 teeth flywheels, such as those for trucks had a bolt pattern for the 11in clutch.
In 1963, the smaller, 153 teeth flywheel was introduced and it ONLY accepted a 10.5 clutch.
The later, 168 teeth flywheels had a bolt pattern for the 11in clutch.
SOME replacement 168 teeth flywheels had a dual bolt pattern for either the 10.5 or 11in clutch.
ALLLLLLLLLLLLLLLLLLL V8 Chevy flywheels for engines with a 2-piece rear main seal have the same bolt pattern for the crankshaft. And ALL V8 flywheels, EXCEPT those for the SB400 and 454 BB, are neutral balance. The SB400 and 454 use the same size 168 teeth flywheels and accept the same 11in clutch, but they have an additional weight on the front side of the flywheel for engine balancing purposes. These 400/454 flywheels are commonly referred to as EXternal balance flywheels.
Here is a comparrison of the 168 teeth neutral and external balance flywheels.
Here is a comparrison of the 153 teeth and a 168 teeth flywheels.
Now, this throws one more fly into the ointment. Depending on which flywheel you choose, you must also have the correct corrosponding size bell housing.
Here is a comparrison of the small and large bell housings.
And then there is still one more issue, the starter. The small flywheel/bell housing requires a starter with the straight across bolt pattern. The large flywheel/bell housing requires a starter with a CAST IRON nose and a staggered bolt pattern. The starter with an alum nose and staggered bolt pattern WILL NOT FIT into the starter bulge of the big bell housing.
Hope this helps.
Tom Parsons
Beginning with the very first Chevy V8 in 1955, there have only been two sizes of flywheels/flexplates:
1. Small, 12 3/4in diameter (frequently referred to as 13in) with 153 teeth.
2. Large, 14in diameter with 168 teeth.
The early flywheels were ONLY the large, 168 teeth version and MOST of them only had a bolt pattern for a 10in clutch (later replacement clutches are now about 10.5in). Some of the early 168 teeth flywheels, such as those for trucks had a bolt pattern for the 11in clutch.
In 1963, the smaller, 153 teeth flywheel was introduced and it ONLY accepted a 10.5 clutch.
The later, 168 teeth flywheels had a bolt pattern for the 11in clutch.
SOME replacement 168 teeth flywheels had a dual bolt pattern for either the 10.5 or 11in clutch.
ALLLLLLLLLLLLLLLLLLL V8 Chevy flywheels for engines with a 2-piece rear main seal have the same bolt pattern for the crankshaft. And ALL V8 flywheels, EXCEPT those for the SB400 and 454 BB, are neutral balance. The SB400 and 454 use the same size 168 teeth flywheels and accept the same 11in clutch, but they have an additional weight on the front side of the flywheel for engine balancing purposes. These 400/454 flywheels are commonly referred to as EXternal balance flywheels.
Here is a comparrison of the 168 teeth neutral and external balance flywheels.
Here is a comparrison of the 153 teeth and a 168 teeth flywheels.
Now, this throws one more fly into the ointment. Depending on which flywheel you choose, you must also have the correct corrosponding size bell housing.
Here is a comparrison of the small and large bell housings.
And then there is still one more issue, the starter. The small flywheel/bell housing requires a starter with the straight across bolt pattern. The large flywheel/bell housing requires a starter with a CAST IRON nose and a staggered bolt pattern. The starter with an alum nose and staggered bolt pattern WILL NOT FIT into the starter bulge of the big bell housing.
Hope this helps.
Tom Parsons
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I will be taking it to them tomorrow to have the balance checked.
Hopefully the machine shop will be finished with my heads (my third, or is it fouth promised date?) and I'll be able to get on with assembly.
Now I know why everyone buys crate engines!
PS. Unless you're doing something really, really wild with your 327, a 10.5 in clutch should be more than adequate.
DT
Last edited by NOM61; 09-08-2010 at 08:32 PM.
#13
Melting Slicks
Check out a similar, if not identical flywheel from Advance Auto:
http://shop.advanceautoparts.com/web...492-_-10720525
I have an identical appearing one in my shop now - it's a GM Performance Parts 153 tooth flywheel (p/n 14085720 1955–1985 12.750" 3.580" 10.400" 153 For 2-piece crank seal. Lightweight nodular iron; weighs approximately 15 pounds). It has worked fine. BTW, the new price from Advance for this flywheel is less than half what I paid.
Also, I measured the machined surface of this GM flywheel and it's only 10.75 inches. I seriously doubt that an 11" clutch and pressure plate will work. On all three of these, there's only one set of 6 holes all at the same radius.
Let us know if an 11" clutch will really work - but I doubt it. Otherwise, the picture shown on the eBay ad may not be correct.
http://shop.advanceautoparts.com/web...492-_-10720525
I have an identical appearing one in my shop now - it's a GM Performance Parts 153 tooth flywheel (p/n 14085720 1955–1985 12.750" 3.580" 10.400" 153 For 2-piece crank seal. Lightweight nodular iron; weighs approximately 15 pounds). It has worked fine. BTW, the new price from Advance for this flywheel is less than half what I paid.
Also, I measured the machined surface of this GM flywheel and it's only 10.75 inches. I seriously doubt that an 11" clutch and pressure plate will work. On all three of these, there's only one set of 6 holes all at the same radius.
Let us know if an 11" clutch will really work - but I doubt it. Otherwise, the picture shown on the eBay ad may not be correct.
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There is no such thing as a 10.5 or 11in flywheel.
Beginning with the very first Chevy V8 in 1955, there have only been two sizes of flywheels/flexplates:
1. Small, 12 3/4in diameter (frequently referred to as 13in) with 153 teeth.
2. Large, 14in diameter with 168 teeth.
The early flywheels were ONLY the large, 168 teeth version and MOST of them only had a bolt pattern for a 10in clutch (later replacement clutches are now about 10.5in). Some of the early 168 teeth flywheels, such as those for trucks had a bolt pattern for the 11in clutch.
In 1963, the smaller, 153 teeth flywheel was introduced and it ONLY accepted a 10.5 clutch.
The later, 168 teeth flywheels had a bolt pattern for the 11in clutch.
SOME replacement 168 teeth flywheels had a dual bolt pattern for either the 10.5 or 11in clutch.
ALLLLLLLLLLLLLLLLLLL V8 Chevy flywheels for engines with a 2-piece rear main seal have the same bolt pattern for the crankshaft. And ALL V8 flywheels, EXCEPT those for the SB400 and 454 BB, are neutral balance. The SB400 and 454 use the same size 168 teeth flywheels and accept the same 11in clutch, but they have an additional weight on the front side of the flywheel for engine balancing purposes. These 400/454 flywheels are commonly referred to as EXternal balance flywheels.
Here is a comparrison of the 168 teeth neutral and external balance flywheels.
Here is a comparrison of the 153 teeth and a 168 teeth flywheels.
Now, this throws one more fly into the ointment. Depending on which flywheel you choose, you must also have the correct corrosponding size bell housing.
Here is a comparrison of the small and large bell housings.
And then there is still one more issue, the starter. The small flywheel/bell housing requires a starter with the straight across bolt pattern. The large flywheel/bell housing requires a starter with a CAST IRON nose and a staggered bolt pattern. The starter with an alum nose and staggered bolt pattern WILL NOT FIT into the starter bulge of the big bell housing.
Hope this helps.
Tom Parsons
Beginning with the very first Chevy V8 in 1955, there have only been two sizes of flywheels/flexplates:
1. Small, 12 3/4in diameter (frequently referred to as 13in) with 153 teeth.
2. Large, 14in diameter with 168 teeth.
The early flywheels were ONLY the large, 168 teeth version and MOST of them only had a bolt pattern for a 10in clutch (later replacement clutches are now about 10.5in). Some of the early 168 teeth flywheels, such as those for trucks had a bolt pattern for the 11in clutch.
In 1963, the smaller, 153 teeth flywheel was introduced and it ONLY accepted a 10.5 clutch.
The later, 168 teeth flywheels had a bolt pattern for the 11in clutch.
SOME replacement 168 teeth flywheels had a dual bolt pattern for either the 10.5 or 11in clutch.
ALLLLLLLLLLLLLLLLLLL V8 Chevy flywheels for engines with a 2-piece rear main seal have the same bolt pattern for the crankshaft. And ALL V8 flywheels, EXCEPT those for the SB400 and 454 BB, are neutral balance. The SB400 and 454 use the same size 168 teeth flywheels and accept the same 11in clutch, but they have an additional weight on the front side of the flywheel for engine balancing purposes. These 400/454 flywheels are commonly referred to as EXternal balance flywheels.
Here is a comparrison of the 168 teeth neutral and external balance flywheels.
Here is a comparrison of the 153 teeth and a 168 teeth flywheels.
Now, this throws one more fly into the ointment. Depending on which flywheel you choose, you must also have the correct corrosponding size bell housing.
Here is a comparrison of the small and large bell housings.
And then there is still one more issue, the starter. The small flywheel/bell housing requires a starter with the straight across bolt pattern. The large flywheel/bell housing requires a starter with a CAST IRON nose and a staggered bolt pattern. The starter with an alum nose and staggered bolt pattern WILL NOT FIT into the starter bulge of the big bell housing.
Hope this helps.
Tom Parsons
#15
Le Mans Master
Check out a similar, if not identical flywheel from Advance Auto:
I have an identical appearing one in my shop now - it's a GM Performance Parts 153 tooth flywheel (p/n 14085720 1955–1985 12.750" 3.580" 10.400" 153 For 2-piece crank seal. Lightweight nodular iron; weighs approximately 15 pounds). It has worked fine. BTW, the new price from Advance for this flywheel is less than half what I paid.
Also, I measured the machined surface of this GM flywheel and it's only 10.75 inches. I seriously doubt that an 11" clutch and pressure plate will work. On all three of these, there's only one set of 6 holes all at the same radius.
Let us know if an 11" clutch will really work - but I doubt it. Otherwise, the picture shown on the eBay ad may not be correct.
I have an identical appearing one in my shop now - it's a GM Performance Parts 153 tooth flywheel (p/n 14085720 1955–1985 12.750" 3.580" 10.400" 153 For 2-piece crank seal. Lightweight nodular iron; weighs approximately 15 pounds). It has worked fine. BTW, the new price from Advance for this flywheel is less than half what I paid.
Also, I measured the machined surface of this GM flywheel and it's only 10.75 inches. I seriously doubt that an 11" clutch and pressure plate will work. On all three of these, there's only one set of 6 holes all at the same radius.
Let us know if an 11" clutch will really work - but I doubt it. Otherwise, the picture shown on the eBay ad may not be correct.
I have one behind my 439. It's perfect for me.
I have a Centerforce II.
A fun factoid... Smokey wrote the small flywheel and clutch
have way less chance of exploding.
#16
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A point on the perimeter of the larger diameter flywheel/clutch travels further in the same amount of time at a given rpm than a similar point on the perimeter of the smaller flywheel/clutch.
More distance in the same time equals higher velocity equals more energy and more stress on the flywheel/clutch.
And since the centripital force increases with the square of the velocity, increases in diameter can have a dramatic effect on the amount of force that is basically trying to pull the flywheel apart (technically the force is pulling toward the center of the flywheel and is provided by the tensile strength of the flywheel).
If this centripital force exceeds the tensile strength of the flywheel/clutch, kaboom!
DT
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I was just paraphrasing the listing.
Below is what I received. The face measures 11 1/16".
I've never had, used or seen an 11" chevy clutch so I have no idea if one will work on this flywheel - like I said, just paraphasing the listing.
If this is actually what it was sold as and not a chinese knockoff, it is listed at Jegs and Summit for over $250.
The seller lists it as 17#. Jegs lists it as 16#.
McLeod does not list it in their current inventory, so I'm hoping its a discontinued flywheel that someone bought of bunch of on closeout.
Here are the pics:
DT
#19
Melting Slicks
Two more items to complete the very thorough review from DZ.
If you're using the 153 tooth flywheel/bellhousing/starter on a big block (I am) you will have to use a '65 396 or L-88 starter brace.
The 153 tooth neutral balance flywheels come in two varieities. One is a 37 pounder with full metal thickness across the entire back face. It's the standard C2 small block flywheel. The other is a 16 pound nodular iron unit that has thin metal except for the friction face area. You used to be able to find those by the dozens in the used parts bins at the local speed shop, but not any more. I'm trying to find one for my 427. Makes 'em rev like a 302. God help me I don't feel like pulling the trans out after the car comes back from the body shop though.
If you're using the 153 tooth flywheel/bellhousing/starter on a big block (I am) you will have to use a '65 396 or L-88 starter brace.
The 153 tooth neutral balance flywheels come in two varieities. One is a 37 pounder with full metal thickness across the entire back face. It's the standard C2 small block flywheel. The other is a 16 pound nodular iron unit that has thin metal except for the friction face area. You used to be able to find those by the dozens in the used parts bins at the local speed shop, but not any more. I'm trying to find one for my 427. Makes 'em rev like a 302. God help me I don't feel like pulling the trans out after the car comes back from the body shop though.
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So are the lightweight GM 153 teeth flywheels worth much? I have one deep in my stack of flywheels that's never been bolted to a crank.
Tom Parsons
Tom Parsons