Torque plate hone a BBM ?

flyingwedge · Post by **flyingwedge** » Mon Jun 30, 2014 7:43 pm

How important really ? Non race 400, with a 4.15" arm. Sbc's twist their bores, with open deck bolt holes. relatively close to the bores. Maybe the mopar doesn't need this ? Thanks, flyingwedge.

wil8115 · Post by **wil8115** » Mon Jun 30, 2014 7:56 pm

if we have a plate for it we use one.. simulate how it'll be while running will help get best ring seal.

k-star · Post by **k-star** » Mon Jun 30, 2014 8:29 pm

Not sure about the B blocks but the RB's are bad with out a plate, at least the few I have done.

Keith

CNC BLOCKS · Post by **CNC BLOCKS** » Mon Jun 30, 2014 9:16 pm

If your going with better fasteners you will see more distortion over stock hardware, Plate hone for the best results.

MotionMachine · Post by **MotionMachine** » Mon Jun 30, 2014 9:25 pm

Definitely need a plate and you'd better sonic test it. I have a 400 here now that is .110" on the thrust side in one cylinder.

TMSJoe · Post by **TMSJoe** » Mon Jun 30, 2014 9:27 pm

The Chevy blocks definitely pull away near the bolts. I use the plate on all the BBMs because I have it. I have not seen any radical distortion on the Mopar stuff.

cpmotors · Post by **cpmotors** » Mon Jun 30, 2014 10:37 pm

413 I had come in a few years ago with a few issues. Like Keith said, they move a fair amount IMO.

wyrmrider · Post by **wyrmrider** » Mon Jun 30, 2014 11:24 pm

Built lots of BBM's
your mileage will vary
but bore as little as possible and use the plate and gaskets type to be used
surface the block square first- they can be way off
bottom tap all blind bolts
I've found broken tap ends in the man holes and "short drilled" holes
MOPAR resharpens it's drill bits and taps so if you get ones at end of life...
have the mains torqued down
use a 440 rod, direct connection rod bolts are SPS and a good value

flyingwedge · Post by **flyingwedge** » Tue Jul 01, 2014 11:07 am

Ok, Non race motor, short deck and I need to sonic test for .040 over ? Rod ratio 1.63. Do I also need a partial block fill ? I'm considering steel caps, bore mains for 2.75 journal,(what crank has), or grind mains to 2.625 ? I will likely need to reduce counterweight diameters. Thanks all, flyingwedge.

wyrmrider · Post by **wyrmrider** » Tue Jul 01, 2014 11:41 am

flying wedge
check for ring availability before buying pistons
stock bore is 4.340
Is the block .030 already? 4.370? The blocks are reasonably hard and often do not require boring unless damaged
BTW 4.350 is a common 100 over size for BBC so widely available (also .030 over 440)
let me know what you come up with for rings
no need for steel caps if mild engine-
I've done it for Hemi Conversion but that's a lot of work what with welding in bosses for the head studs etc.
is yours the "heavy block"
there are websites with photos of the main webbing
what's your rod length?
the 440 rods will keep the pistons from coming out the bottom of the block and hitting the crank, also give a lighter piston
Mallory for a balance with short rods and some kits have the piston top to deck too large
BVVC
what heads? ft or roller cam?

flyingwedge · Post by **flyingwedge** » Tue Jul 01, 2014 11:58 am

Aug 74' block. Icon dish pistons, Total Seal file or gapless rings. 440 length,"Source H-beam" rods. Mild Comp. hyd roller,( 6k max rpm.)? Indy SR or ProComp alum. heads, SP 4bbl. Pump gas only. I consider steel caps, only because of max stroke.I prefer NOT to block fill. Thought is to use RPM/moly cross bolt caps, precision notch the pan rails, to fit cap, without cross bolts. I have a non-auto machine shop/ kinda fun. Thanks, flyingwedge.

wyrmrider · Post by **wyrmrider** » Tue Jul 01, 2014 10:24 pm

File fit ductile top, napier second
if you do not have the rods the stock 440 rods with DC bolts work fine, but I have ability to side grind and shot peen
I have a few sets all magged, side ground etc if you could use them but you have to be able to rebuild the big ends
rest of your list looks good
do deck the block first
Icon dished pistons- or KB excellent choices
I'd let mike jones do the cam
do not think you need steel caps unless you are missing the stock one
windage tray and oiling mods are more important
I had a 73 400 (AT) that lost the thrust so i suggest thrust mods
does your block have large thrust or small thrust dia?

agertz1 · Post by **agertz1** » Fri Jan 07, 2022 11:48 am

My "back burner" is too slow. Came to my senses, just a 451" build with forged, oem. 440 crank. H beam, 6.76" rods. Likely steel center (3) main caps. I "think"
I can use my cylinder boring bar to rough the mains bores, to prep for honing ?
Art.

MotionMachine · Post by **MotionMachine** » Fri Jan 07, 2022 9:52 pm

"I can use my cylinder boring bar to rough the mains bores, to prep for honing ?"

????????????????????????!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

dondon · Post by **dondon** » Sat Jan 08, 2022 2:19 pm

i did a bbm years back and when setting the end gap on the rings I noticed that that piston was tight putting it in with the wrist pin parallel to the crank center line, but if I turned the piston 90 degrees it slid it just fine. It was bored and honed with a torque plate. machine shop said it would be OK after the head was torqued on.

Don Terrill’s Speed-Talk

Torque plate hone a BBM ?

Torque plate hone a BBM ?

Re: Torque plate hone a BBM ?

Re: Torque plate hone a BBM ?

Re: Torque plate hone a BBM ?

Re: Torque plate hone a BBM ?

Re: Torque plate hone a BBM ?

Re: Torque plate hone a BBM ?

Re: Torque plate hone a BBM ?

Re: Torque plate hone a BBM ?

Re: Torque plate hone a BBM ?

Re: Torque plate hone a BBM ?

Re: Torque plate hone a BBM ?

Re: Torque plate hone a 400 BBM ?

Re: Torque plate hone a BBM ?

Re: Torque plate hone a BBM ?