SFI flywheel
Thread Starter
Safety Car
Joined: Jan 2008
Posts: 3,795
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From: Aarhus, Denmark
SFI flywheel
I'm doing a M21 to T5 swap right now. (69 L46 convertible)
My plan is to replace the factory 11" clutch flywheel, with a SFI 23lbs flywheel.
BUT I can see that the thickness of the factory flywheel is 30mm, the SFI is 23mm
I'm using the same clutch, will the 7-8mm difference give me problems?
My plan is to replace the factory 11" clutch flywheel, with a SFI 23lbs flywheel.
BUT I can see that the thickness of the factory flywheel is 30mm, the SFI is 23mm
I'm using the same clutch, will the 7-8mm difference give me problems?
Last edited by c3_dk; Oct 24, 2017 at 03:30 PM.
Thread Starter
Safety Car
Joined: Jan 2008
Posts: 3,795
Likes: 435
From: Aarhus, Denmark
Thread Starter
Safety Car
Joined: Jan 2008
Posts: 3,795
Likes: 435
From: Aarhus, Denmark
As far as I can see, it is this one, it is 0.28" longer then std, I think std. is 1.5"
0.28" = 7.11mm
Correct??
https://www.ebay.com/itm/Chevrolet-P...BYOMQ-&vxp=mtr
0.28" = 7.11mm
Correct??
https://www.ebay.com/itm/Chevrolet-P...BYOMQ-&vxp=mtr
Last edited by c3_dk; Oct 24, 2017 at 05:10 PM.
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
Gm long ball stud 3790556. I never liked the adjusable type but they are an option
http://www.manchestermuncies.com/new...ball-stud.html
http://www.manchestermuncies.com/new...ball-stud.html
Thread Starter
Safety Car
Joined: Jan 2008
Posts: 3,795
Likes: 435
From: Aarhus, Denmark
Gm long ball stud 3790556. I never liked the adjusable type but they are an option
http://www.manchestermuncies.com/new...ball-stud.html
http://www.manchestermuncies.com/new...ball-stud.html
Here is what is it today.
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
GM 3790556 Clutch Fork Ball Stud (1 3/4 Long) Or 1.750 - 1.369 =.381 =9.6774 mm
You only needed 7-8mm, but a couple of mm is not a big deal. It is just the pivot point for your clutch fork rod. I installed a 21 pound SFI steel 168 tooth flywheel in front of my tko 600 and with the short ball stud sent by keisler the clutch would not disengage. So I went down to the local chevy dealer and bought the longer one
You only needed 7-8mm, but a couple of mm is not a big deal. It is just the pivot point for your clutch fork rod. I installed a 21 pound SFI steel 168 tooth flywheel in front of my tko 600 and with the short ball stud sent by keisler the clutch would not disengage. So I went down to the local chevy dealer and bought the longer one
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Thread Starter
Safety Car
Joined: Jan 2008
Posts: 3,795
Likes: 435
From: Aarhus, Denmark
GM 3790556 Clutch Fork Ball Stud (1 3/4 Long) Or 1.750 - 1.369 =.381 =9.6774 mm
You only needed 7-8mm, but a couple of mm is not a big deal. It is just the pivot point for your clutch fork rod. I installed a 21 pound SFI steel 168 tooth flywheel in front of my tko 600 and with the short ball stud sent by keisler the clutch would not disengage. So I went down to the local chevy dealer and bought the longer one
You only needed 7-8mm, but a couple of mm is not a big deal. It is just the pivot point for your clutch fork rod. I installed a 21 pound SFI steel 168 tooth flywheel in front of my tko 600 and with the short ball stud sent by keisler the clutch would not disengage. So I went down to the local chevy dealer and bought the longer one
So I hope I will have it next week, so I can install my transmission again.
Almost same flywheel here, 23 pound, 168 tooth, so I hope I can fell the change compared to the factory flywheel, but also with the first gear ration in the T5 compared to the "slow" M21
Le Mans Master
Joined: Oct 2006
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From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
Watch the flywheel bolts too- I just put an SFI 'wheel on my 496. The thickness of the hub was less and the ends of the flywheel bolts were way too close to the block for me. I cut about 3 threads off each bolt. Still have a couple of threads thru the flywheel flange.
Thread Starter
Safety Car
Joined: Jan 2008
Posts: 3,795
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From: Aarhus, Denmark
Great info here !! THX !!
When I measure my stock 69 fly wheel, like picture number one it is 0.990" (picture says 0.960")
The SFI is 0.722"
0.990 - 0.722 = 0.268" = 6.8mm
And as George is saying "GM 3790556 Clutch Fork Ball Stud (1 3/4 Long) Or 1.750 - 1.369 =.381 =9.6774 mm"
6.8mm - 9.677 = 2.877mm
/John
Thread Starter
Safety Car
Joined: Jan 2008
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From: Aarhus, Denmark
Thx for the heads up !!
/John
Le Mans Master
Joined: Oct 2006
Posts: 7,123
Likes: 433
From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
You have about double what I had before I cut the bolts down.
FWIW: I just found the numbers for my clutch ball height:
Flywheel deck .690
The factory ball height 5.112 (Lakewood housing and block plate.
The factory ball height explains why I always had very little travel on the clutch adjustment.
I got a longer adjustable ball and got the height right back to the factory 4.75. Clutch adjustment is midway on the rod now.
FWIW: I just found the numbers for my clutch ball height:
Flywheel deck .690
The factory ball height 5.112 (Lakewood housing and block plate.
The factory ball height explains why I always had very little travel on the clutch adjustment.
I got a longer adjustable ball and got the height right back to the factory 4.75. Clutch adjustment is midway on the rod now.
Last edited by TimAT; Oct 28, 2017 at 09:47 PM.
Thread Starter
Safety Car
Joined: Jan 2008
Posts: 3,795
Likes: 435
From: Aarhus, Denmark
You have about double what I had before I cut the bolts down.
FWIW: I just found the numbers for my clutch ball height:
Flywheel deck .690
The factory ball height 5.112 (Lakewood housing and block plate.
The factory ball height explains why I always had very little travel on the clutch adjustment.
I got a longer adjustable ball and got the height right back to the factory 4.75. Clutch adjustment is midway on the rod now.
FWIW: I just found the numbers for my clutch ball height:
Flywheel deck .690
The factory ball height 5.112 (Lakewood housing and block plate.
The factory ball height explains why I always had very little travel on the clutch adjustment.
I got a longer adjustable ball and got the height right back to the factory 4.75. Clutch adjustment is midway on the rod now.
Where do I measure from, what is a block saver plate?
I think I will go for Nord Lock washers, that will give the 2mm I need compared to the factory washers.
http://www.nord-lock.com/nord-lock/w.../introduction/
Last edited by c3_dk; Oct 29, 2017 at 03:20 AM.
Le Mans Master
Joined: Oct 2006
Posts: 7,123
Likes: 433
From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
The block saver plate fits between an explosion proof bell housing and the block. All for containment if the flywheel/clutch comes apart.
Lay a straightedge across the engine side of your bell housing so it's over the clutch pivot ball. Then measure from the mating surface to the top of the ball. Look at fig.2 on the red outline picture buns posted.
Lay a straightedge across the engine side of your bell housing so it's over the clutch pivot ball. Then measure from the mating surface to the top of the ball. Look at fig.2 on the red outline picture buns posted.
Thread Starter
Safety Car
Joined: Jan 2008
Posts: 3,795
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From: Aarhus, Denmark
The block saver plate fits between an explosion proof bell housing and the block. All for containment if the flywheel/clutch comes apart.
Lay a straightedge across the engine side of your bell housing so it's over the clutch pivot ball. Then measure from the mating surface to the top of the ball. Look at fig.2 on the red outline picture buns posted.
Lay a straightedge across the engine side of your bell housing so it's over the clutch pivot ball. Then measure from the mating surface to the top of the ball. Look at fig.2 on the red outline picture buns posted.
Thx gkull