> When I rebuilt my 540CAD I used a torque plate to bore and hone the
> cylinder.
> It is amassing how the bolts when torqued will show up on the walls.
> I'm now too old to waste time and money on those luxuries.
> Still have the Torque plate I will let go for cheap.
>
> On Fri, Oct 16, 2020 at 6:11 PM James Hupy via Gmclist <
>
> > A technical instructor at the GM Training Center near Portland, where I got
> > much of my Oldsmobile training, demonstrated on a 400 SB Chev block on the
> > flimsy bore stability. He took a telescoping gage, set it so it would stay
> > in the bore by itself, then, using only his hands, squeezing the bore
> > sides. This caused the telescoping gage to fall right out of the bottom. I
> > had no idea they were that flimsy. Wouldn't happen on a 455 Olds, I am
> > sure. He didn't have much love for the V-6's either. Nor did I.
> > Jim Hupy
> > Salem, Oregon
> >
> >
> >>> When cylinders are bored, often times, particularly with non-robust
> >> engine blocks, cylinder bore stabilization plates are used. They are
> > purpose
> >>> built, very thick, very dimensionally stable, plates that simulate a
> >> cylinder head. The bores in the engine match bores in the plate that
> > allow
> >>> boring machinery, (cutters or hones) access to the engine cylinder
> > bores
> >> for re-machining. The bore plates are torqued down on the cylinder
> > blocks,
> >>> and cylinders are re-machined. Then after re-machining, the bore plates
> >> are removed, and the rest of the machining is completed to the blocks.
> > Then,
> >>> when the engine is re-assembled, the cylinder head torque matches what
> >> the torque plate torque was, and the bore shape supposedly is round.
> >>> Engines like the small block 5 litre Ford, and yes, the Olds 403,
> >> benefit from this extra step. Like Matt says, overtorquing from
> >>> retightening the head bolts, can distort the thin wall engine blocks.
> >>> So, It's a crap shoot. In my opinion based upon personal
> >> experience in machine shops, it is probably best to not molest it if
> >> possible.
> >>> Jim Hupy
> >>> Salem, Oregon
> >>
> >> Jim, when we did this, we found three essentials:
> >> The plate had to be more than just a solid plate, it had to be machined
> > so
> >> as to duplicate the flexibility of the cylinder head casting.
> >> It (of course) had to be put down at the design fastener tension. We
> > used
> >> gages that measured the bolt tension.
> >> You had to use it with the headgasket that was planned for the final
> >> assembly.
> >>
> >> The Ford 302 was way better than the 2.3l particularly in the SVO
> > version,
> >> but one of the worse was the Chevy SB 400 and you can guess why.
> >> It was a siamese bore (like the 403) but there was no metal left.
> >>
> >> Great days - those were? We made it all work. A 455 is easy.
> >>
> >> Matt
> >> --
> >> Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL,
> >> GMCES
> >> Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum
> >> Brakes with Applied Control Arms
> >> SE Michigan - Near DTW - Twixt A2 and Detroit
> >>
> >> _______________________________________________
> >> GMCnet mailing list
> >> Unsubscribe or Change List Options:
> >> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
> >>
> > _______________________________________________
> > GMCnet mailing list
> > Unsubscribe or Change List Options:
> > http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
> >
>
>
> --
> Jim Kanomata
> Applied/GMC, Newark,CA
> jimk
> http://www.gmcrvparts.com
> 1-800-752-7502
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
Your PM not working, so sent and email.
--
Larry
78 Royale w/500 Caddy
Menomonie, WI.
> cylinder.
> It is amassing how the bolts when torqued will show up on the walls.
> I'm now too old to waste time and money on those luxuries.
> Still have the Torque plate I will let go for cheap.
>
> On Fri, Oct 16, 2020 at 6:11 PM James Hupy via Gmclist <
>
> > A technical instructor at the GM Training Center near Portland, where I got
> > much of my Oldsmobile training, demonstrated on a 400 SB Chev block on the
> > flimsy bore stability. He took a telescoping gage, set it so it would stay
> > in the bore by itself, then, using only his hands, squeezing the bore
> > sides. This caused the telescoping gage to fall right out of the bottom. I
> > had no idea they were that flimsy. Wouldn't happen on a 455 Olds, I am
> > sure. He didn't have much love for the V-6's either. Nor did I.
> > Jim Hupy
> > Salem, Oregon
> >
> >
> >>> When cylinders are bored, often times, particularly with non-robust
> >> engine blocks, cylinder bore stabilization plates are used. They are
> > purpose
> >>> built, very thick, very dimensionally stable, plates that simulate a
> >> cylinder head. The bores in the engine match bores in the plate that
> > allow
> >>> boring machinery, (cutters or hones) access to the engine cylinder
> > bores
> >> for re-machining. The bore plates are torqued down on the cylinder
> > blocks,
> >>> and cylinders are re-machined. Then after re-machining, the bore plates
> >> are removed, and the rest of the machining is completed to the blocks.
> > Then,
> >>> when the engine is re-assembled, the cylinder head torque matches what
> >> the torque plate torque was, and the bore shape supposedly is round.
> >>> Engines like the small block 5 litre Ford, and yes, the Olds 403,
> >> benefit from this extra step. Like Matt says, overtorquing from
> >>> retightening the head bolts, can distort the thin wall engine blocks.
> >>> So, It's a crap shoot. In my opinion based upon personal
> >> experience in machine shops, it is probably best to not molest it if
> >> possible.
> >>> Jim Hupy
> >>> Salem, Oregon
> >>
> >> Jim, when we did this, we found three essentials:
> >> The plate had to be more than just a solid plate, it had to be machined
> > so
> >> as to duplicate the flexibility of the cylinder head casting.
> >> It (of course) had to be put down at the design fastener tension. We
> > used
> >> gages that measured the bolt tension.
> >> You had to use it with the headgasket that was planned for the final
> >> assembly.
> >>
> >> The Ford 302 was way better than the 2.3l particularly in the SVO
> > version,
> >> but one of the worse was the Chevy SB 400 and you can guess why.
> >> It was a siamese bore (like the 403) but there was no metal left.
> >>
> >> Great days - those were? We made it all work. A 455 is easy.
> >>
> >> Matt
> >> --
> >> Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL,
> >> GMCES
> >> Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum
> >> Brakes with Applied Control Arms
> >> SE Michigan - Near DTW - Twixt A2 and Detroit
> >>
> >> _______________________________________________
> >> GMCnet mailing list
> >> Unsubscribe or Change List Options:
> >> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
> >>
> > _______________________________________________
> > GMCnet mailing list
> > Unsubscribe or Change List Options:
> > http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
> >
>
>
> --
> Jim Kanomata
> Applied/GMC, Newark,CA
> jimk
> http://www.gmcrvparts.com
> 1-800-752-7502
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
Your PM not working, so sent and email.
--
Larry
78 Royale w/500 Caddy
Menomonie, WI.
