Flywheel Teeth Count/ Flywheel Dia. ?
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Instructor
Joined: Aug 2003
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Flywheel Teeth Count/ Flywheel Dia. ?
Does anyone know the no. of teeth and/or diameter of the o.e.m. manual trans flywheel on an '85 350 c.i. ???? I'm planning to swap a 400 c.i. and wonder if the new and required ext. balanced flywheel should be 153 or 168 teeth in order to mesh with the existing starter motor. Anyone having done the "383 thing" should have experienced this. Thanks in advance. Jack
Safety Car
Joined: Jan 2004
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Re: Flywheel Teeth Count/ Flywheel Dia. ? (bigjack)
Single piece seal motors '86 + later are 153 teeth / 12.75 in flywheels.
Book shows same size , different part no for earlier motors has crank flange bolt pattern to suit 2 piece crank seal (which is same as 400 , pre '86)
Book shows same size , different part no for earlier motors has crank flange bolt pattern to suit 2 piece crank seal (which is same as 400 , pre '86)
Race Director
Joined: Sep 2000
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From: The Top of Utah
Re: Flywheel Teeth Count/ Flywheel Dia. ? (bigjack)
All C4s are 153 teeth. All 400s are 168 teeth. The 168 T flywheel won't fit your bellhousing. There are no stock, 153 toothers, with the 400, external balance. GOOD luck, and...
RACE ON!!!
RACE ON!!!
Melting Slicks
Joined: Oct 2000
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From: Heidelberg PA
Cruise-In V Veteran
Re: Flywheel Teeth Count/ Flywheel Dia. ? (CFI-EFI)
Check with TCI. I believe they have either 153 or 168 in same size. I changed my starter to small 168 and the original was a 153. The flywheel came with both bolt patterns.
Good Luck
Good Luck
Racer
Joined: Mar 2004
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From: Oakley Ca
Re: Flywheel Teeth Count/ Flywheel Dia. ? (bigjack)
Jack, most of the above information is correct. I just went through this putting a 383 in my 85. I used a 153 tooth neutral balanced steel flywheel (Hays) and the fellow who did the balancing, balanced the flywheel to work with the Scat crank. A 168 tooth flywheel won't fit in an 85 bell housing. Don't ask how I know. I now have a 30 lb frisbee. :crazy:
Race Director
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From: The Top of Utah
Re: Flywheel Teeth Count/ Flywheel Dia. ? (85vet)
I believe they have either 153 or 168 in same size. I changed my starter to small 168 and the original was a 153. The flywheel came with both bolt patterns.
The two different 'wheels take different starters. Most blocks are drilled for both starters. Forum member, Ralph, got a 400 block that wasn't drilled for the 153 tooth flywheel, starter. Remember all 400s came with 168 teeth. He had to drill and tap his block for the 153 T 'wheel, starter. Good luck, and...
RACE ON!!!
Melting Slicks
Joined: Oct 2000
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From: Heidelberg PA
Cruise-In V Veteran
Re: Flywheel Teeth Count/ Flywheel Dia. ? (CFI-EFI)
I believe they have either 153 or 168 in same size. I changed my starter to small 168 and the original was a 153. The flywheel came with both bolt patterns. First: Both tooth count flywheels are not, can NOT, be the same size. If they WERE the same size, why did you change starters? The bolt pattern you refer to has to be converter bolt patterns.
The two different 'wheels take different starters. Most blocks are drilled for both starters. Forum member, Ralph, got a 400 block that wasn't drilled for the 153 tooth flywheel, starter. Remember all 400s came with 168 teeth. He had to drill and tap his block for the 153 T 'wheel, starter. Good luck, and...
RACE ON!!!
The two different 'wheels take different starters. Most blocks are drilled for both starters. Forum member, Ralph, got a 400 block that wasn't drilled for the 153 tooth flywheel, starter. Remember all 400s came with 168 teeth. He had to drill and tap his block for the 153 T 'wheel, starter. Good luck, and...
RACE ON!!!
[Modified by 85vet, 9:27 PM 3/24/2004]
Race Director
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From: The Top of Utah
Re: Flywheel Teeth Count/ Flywheel Dia. ? (85vet)
CFI-EFI: My original starter 153 was used on my 4+3. Due to header constraints and a change to a 700r4 tranny, I went with a smaller high torque starter for $129 that required me to go with the 168 tooth. My 350 block did have both bolt patterns so I had no problem changing starters.
As you learned, either flex plate will fit. The problem is with flywheels.
RACE ON!!!
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Melting Slicks
Joined: Oct 2000
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From: Heidelberg PA
Cruise-In V Veteran
Re: Flywheel Teeth Count/ Flywheel Dia. ? (CFI-EFI)
CFI-EFI,
The mini starter I am using is not a racing starter. I went to a local starter rebuilder and purchased a heavy duty mini starter that uses the offset bolt holes, unlike the original monster that uses two in-line bolts.
I do not disagree with your flex plate statement.
The mini starter I am using is not a racing starter. I went to a local starter rebuilder and purchased a heavy duty mini starter that uses the offset bolt holes, unlike the original monster that uses two in-line bolts.
I do not disagree with your flex plate statement.
