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Fine spline in 1977 SBC

O

oldshore

Contributing Member
"Upon disassembly of my 1977 f

"Upon disassembly of my 1977 flywheel cover from the primary driveshaft housing (Volvo 280 drive) I noticed the shaft has the fine (26 spline) variation instead of the coarse variation. I have a 12 3/4" flywheel. I was under the impression that generation flywheel could only mate to a coarse spline in 1977. All parts are original. I am hoping to mate this shaft to the flywheel in my replacement motor, 2003 Crusader 5.7l, without having to replace the flywheel with a post 1986 12 3/4. Is the fine tooth spline unusual in 1977?
Am I correct 26 tooth spline is the fine variation?"
 
"The fine spline was supposedl

"The fine spline was supposedly not around in 1977. If I remember correctly, it first came in the early or mid 80s. The shafts with either the coarse or fine spline in the Chevy bellhousing for the 12 3/4" flywheel (two bearings, no pilot bearing) are interchangeable, and those bellhousings are fairly common (albeit not cheap). However, those bellhousings do not fit the 14" flywheel. The bellhousing for the 14" flywheel is part 3851019 and yes, it has the fine spline

http://www.volvopentastore.com/FLYWHEEL_COVER_PRIM_SHAFT_CLAMPINGRING_KIT_DRIVE_ SP_C1_DP_C1_DP_D/dm/cart_id.753280878--session_id.945909422--store_id.366--view_ id.314273"
 
Thanks Pesc
Remember I have t

Thanks Pesc
Remember I have the 2 piece setup with the standard bobtail borg warner type flywheel cover and the extended primary driveshaft housing. I just did some research and found many Chevy trans. applications with a 26 spline input shaft dating into the early seventies. I will post again when I try to mate the old 26 spline shaft into the "new" motor
 
"Jay, that's interesting,

"Jay, that's interesting, because I always believed the first applications with the fine spline in the PDS were the 290 drives (even the early 290s came with the 10 spline). Did I get it wrong??"
 
"Many years ago, I re-engined

"Many years ago, I re-engined one of these (early, i.e. circa 1969, 2 piece/extended PDS) and was able to get away with just changing the center "spider" on the flywheel from the SBC to the 318 MOPAR I was installing... maybe I just got lucky?"
 
"Jay, out of curiosity, what s

"Jay, out of curiosity, what side of the PDS are you talking about? If you are talking about the side that slides into the flywheel's drive damper, that one has had 26 spline for as long as I can recall. The one I am talking about is the PDS side that slides into the outdrive yoke. To the best of my recollection, that one has had 10 spline until the introduction of the 290 drive in the 1980s, when it went from 10 to 26."
 
"El P is correct.... you shou

"El P is correct.... you should see no fine splines on the aft side (transmission side) on the early ones.

NOTE: most all of the AQ series V-8's used the Borg Warner splines at the all steel drive couplers. This is industry standard for many drives..... I/B's as well.
Only some of the very very early drives would have use a drive coupler spline that more ressembled an older car transmission pilot shaft. Probably a ten or eleven count.... not sure.

Are you by chance confusing aft splines vs the fwd drive coupler splines????
If so, all fwd splines (the B/W drive coupler side) should be the finer B/W style/count.

And, I have never seen any of the extended Volvo Penta PDS/Borg Warner adapters that used fine spline at the aft side..... (Holman Moody or Glastron or Eaton, for example)..... these, to my knowledge, have always been the 10 count since they were early adapters.

Also, maybe worthy of mention..... Volvo Penta also offered a short (standard length) PDS adapter back in the late 70's for the AQ 200B engines. These are identical in dimension to the later "red" one pc flywheel covers.
I have these on my own re-powered boat. (shafts are identical)
All of these are two bearing units.

The Holman Moody, and a few others, were a mix of two and single bearing units depending on which engine.
Fords were likely single bearing with a pilot nose.

What exactly is your delima, if any?

BTW, either flywheel should accept the all steel Borg Warner drive coupler bolt pattern.

."
 
"I was under the impression th

"I was under the impression that I would need a new flywheel (12 3/4" made for the coarse forward spline) for the replacement motor (2003 Crusader 5.7l inboard)to accept the forward spline of the pds. I thought the older forward splines of the pds were coarse tooth. I misunderstood. Since I don't have a Volvo one piece flywheel cover/pdh (made for the 12 3/4 flywheel)but have the 2 piece version, I will simply bolt the pdh to the "new" motor's flywheel cover (borg warner bolt pattern), and the 26 tooth forward spline on the pds should slip right into place. Sorry for the confusion.Thanks for the help.
Jay"
 
"Jay, if this is an AQ series

"Jay, if this is an AQ series drive, you will want to use the 153 tooth flywheel.
There is a 153 tooth fhywheel available for the late engines from a Camero application.
http://bpi.ebasicpower.com/mm5/merchant.mvc?Screen=PROD&Product_Code=QSTFW-1PC12&Store_Code=eBasicPower&search=flywheel&offset=0&filter_cat=&PowerSearch_Begin_Only=&sort=&range_low=&range_high=%26srch_code%3D1%26srch_name%3D1%26srch_pmkeywords%3D1%26srch_pmdescrip%3D1%26srch_mfg%3D1

I don't know of any AQ series flywheel cover (bell housing in the auto world) that works with the 168 tooth flywheel.
Seems that El P linked us to one. I have not looked yet.

Update: OK, I just looked. That F/C may accept the 168.... not sure.

I have a brand spaking new F/C (like the one shown) here if it would solve a problem for you.
Shoot an email if interested.
I also have fine spline yokes in either style ...... (external/internal clips).... in order to make an early transmission U joint shaft work.

."
 
"Thanks Ricardo. I will post w

"Thanks Ricardo. I will post when I get the Velvet Drive taken off my replacement motor, and can see how things fit or don't fit together.
Jay"
 
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