Author Topic: T350 Flexplate with a stamping . . .  (Read 11042 times)

opelitis1

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T350 Flexplate with a stamping . . .
« on: January 18, 2011, 08:38:19 PM »
Going through my flexplates and I came across a plate with a 42 stamping on it.. On the other side of the part is a 1/2" dowel pin I guess there to mate  the crank flange  and the plate.
Have a few T350 flexplates and this is the only one with the dowel pin.. When did they stop coming out with this feature??  Hoping it is common to a '68 396 L35 engine.. Has overspray on it,  could this be from GM as they painted  the engine / transmission assembly??
Thanks!!
Ted

JohnZ

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Re: T350 Flexplate with a stamping . . .
« Reply #1 on: January 19, 2011, 06:24:21 PM »
Automatic-transmission engines were painted with the flexplate in place, so some orange overspray is possible; the transmission wasn't added until much later, at the car assembly plant.

Got a photo of the 1/2" dowel pin in place?
'69 Z/28
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opelitis1

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Re: T350 Flexplate with a stamping . . .
« Reply #2 on: January 20, 2011, 01:03:59 AM »
It's a comin' real soon.  Just got to get me fine lady to gimme a hand in down loading the  pics eh.
 Kinda interesting as this dowel thingy is about a half inch from the ring gear and is about 1/2 inch in diameter.. No way a crank flange is that large..
Ted

opelitis1

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Re: T350 Flexplate with a stamping . . .
« Reply #3 on: January 20, 2011, 01:21:11 AM »
Here they are John!! 
Ted

opelitis1

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Re: T350 Flexplate with a stamping . . .
« Reply #4 on: January 20, 2011, 01:24:32 AM »
Here is the one that was omitted - a closeup of the dowel thingy.
Ted

vtfb68

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Re: T350 Flexplate with a stamping . . .
« Reply #5 on: January 20, 2011, 01:53:45 AM »
Weight? is it from a 400?
VT
68 05C LA RS/SS U2 712 L34 M21 BR
68 08E LA RS Y2 749 L30 M35
67 11B LA  RS/SS M-1 797-Z L48 M21  Convertible

opelitis1

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Re: T350 Flexplate with a stamping . . .
« Reply #6 on: January 20, 2011, 07:11:35 AM »
Possible it was from a T400 but, it does not ring a bell so to speak. Number 42 on it could lead me in right direction but no one yet has stepped up..  Just picked up a copy of Colvin's Corvette by the Numbers 1955 - 1982 and on pg. 114, the imprint of the crank flange on the flex plate looks an awful lot like the 327 flange for  1962 - 1967.
Guess we gonna have to wait for Mr. John Z to help . . .
Thanks!
Ted
 
   

Kelley W King

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Re: T350 Flexplate with a stamping . . .
« Reply #7 on: January 20, 2011, 02:39:02 PM »
Isn,t  the 400 small block externally balanced? I think the flex plate and harmonic balancer do it.
69 Z28 RS Scuncio Hi Performance
69 SS L78
67 SS Chevelle
64 Corvette
66 GTO Tiger Gold
77 Trans Am Special Edition

opelitis1

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Re: T350 Flexplate with a stamping . . .
« Reply #8 on: January 20, 2011, 04:42:28 PM »
Thing is, I never had a 400ci with a crank such as the imprint on the flexplate which is the same as a small journal unit from 1962-67..  Anyone else seen a balance weight such as the one pictured on a T350 or T400 plate?  What does the coding number 42 mean?
Ted

JohnZ

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Re: T350 Flexplate with a stamping . . .
« Reply #9 on: January 20, 2011, 06:28:51 PM »
The offset weight on a 400 flywheel or flexplate was MUCH larger than the "dowel" on that flexplate, which appears to be simply a projection-welded production balancing weight. Don't know what the "42" is.
'69 Z/28
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vtfb68

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Re: T350 Flexplate with a stamping . . .
« Reply #10 on: January 21, 2011, 01:07:11 AM »
Another odd one is the GMC V6.
 VT
68 05C LA RS/SS U2 712 L34 M21 BR
68 08E LA RS Y2 749 L30 M35
67 11B LA  RS/SS M-1 797-Z L48 M21  Convertible

opelitis1

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Re: T350 Flexplate with a stamping . . .
« Reply #11 on: January 21, 2011, 11:34:34 AM »
The original engine for that flexplate could be long-gone by now and most likely is.. What would happen if I put that plate and a balancer together on an engine other than the long-gone one.?

Thing I do not understand is why would they apply the production welded balance weight to the flexplate that allready had  3 balance holes on it??

Did GM balance specific parts that would be working together before engine assembly??

Thanks!!

JohnZ

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Re: T350 Flexplate with a stamping . . .
« Reply #12 on: January 21, 2011, 10:25:19 PM »
The original engine for that flexplate could be long-gone by now and most likely is.. What would happen if I put that plate and a balancer together on an engine other than the long-gone one.?

Thing I do not understand is why would they apply the production welded balance weight to the flexplate that allready had  3 balance holes on it??

Did GM balance specific parts that would be working together before engine assembly??

Thanks!!

There are no other "balance holes" on that flexplate. All rotating parts were specified to be neutral-balanced (except on 400's and 454's, which were externally-balanced, and on one-piece rear seal 350's, which used an offset-weighted flywheel/flexplate).
'69 Z/28
Fathom Green
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opelitis1

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Re: T350 Flexplate with a stamping . . .
« Reply #13 on: January 22, 2011, 02:24:09 AM »
Good evening John!!
Please advise what the (3) indentures are on the flexplate at  the 3 o'clock position in pics 1 and 2 - i.e. same photo. 
Just saw an ORIGINAL  maybe 66 Vette go over the block at BJ and the $$ it brought.. Was completely original down to some paint imperfection(s) on psgr door.  I'd rather see machines like that in their innocence than re-done re-painted to the max units.
Thanks John!!
Ted

JohnZ

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Re: T350 Flexplate with a stamping . . .
« Reply #14 on: January 22, 2011, 04:23:05 PM »
Good evening John!!
Please advise what the (3) indentures are on the flexplate at  the 3 o'clock position in pics 1 and 2 - i.e. same photo.

I have no idea what those indentations are, but they don't affect balance.
'69 Z/28
Fathom Green
CRG