Torque plate blueprint, or possibly rent one?

[steve hackel]

My rebuilder and I are looking for either a blueprint for an 8ba torque plate, or the possibility of renting one from someone so we can finish the bore and honing of the block so we can move onto other more pressing things. Just a side question; would it be possible to use this plate for pressure testing the block? Thanks, Steve

[flatjack9]

Take a cylinder head and bore out the holes over the pistons. It then can be used to pressure test also --- NOT

[Brian]

Sorry Jack, if one bores a head out over the cylinders, you'll be into water passages so can't use for pressure test. Would make torque plate ok.

[JSeery]

A cylinder head should be a good pattern for a torque plate. And it would work well for pressure testing as well.

[Fordestes]

I took a 2 inch thick piece of aluminum drilled the plate while using the head as a bolt pattern then took an old piston that had a small centering hole in it then drilled out the center and sharp pointed a bolt and screwed it in the center hole and after bolting the already drilled plate to the block I tapped the piston with the bolt centered in the old piston as a pilot hole to use as a starting point, scratched the diameter of the cylinder bore as a reference point then drilled and bored a 3-3/8 hole for the cylinders , bolted it down and used a neoprene gasket as a seal then used it as a pressure tool and a torque plate. I had to have the plate surfaced to get an accurate even torque and seal the pressure head gasket, I later counter bored the hone plate to accept allen head counter sunk bolts.

[flatrod]

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I have one, but being way up here in Alaska, probably not worth shipping back and forth. It should be easy to make.

[steve hackel]

I appreciate all the suggestions & directions, but I do not have any cylinder heads to either bore one out for a torque plate or even use one for a pattern, so I am out there asking for a blueprint to make one. Just a side bar question, if I find a single cylinder head (left or right) would that one head work for both sides as a boring / torque plate or do I need left & right examples? I guess I could search Craigs list around here for one.

[Bored&Stroked]

I have complete deck surface CAD models - in 3D SolidWorks formats (for custom cylinder heads).

I'd be happy to make a 'deck surface plate' model for you - if you're going to use a CNC milling machine to do the work (which is how I'd do it).

If you're just going to manually make a plate - just using an old head to 'center punch' an aluminum plate would be the easiest.

If you're thinking CNC and somebody understands what I'm saying about SolidWorks CAD models (or DXF files) then I'd be happy to work with you. Obviously whatever CNC program you're using - you'd need to be able to import SolidWorks 3D models and/or DXF 2D vector files to build your machining tool paths from. So if this is the approach you're taking, let me know.

The only stipulation or catch is that if you go the CNC approach, I'd like to have a deck plate as a result. I'm happy to pay for materials and help the process through - maybe we can make it a "win win" for all involved.

Anybody have CNC capabilities and want to get on board . . . just PM me.

Best of luck,

Dale

[Yoyodyne]

Originally Posted by steve hackel

I appreciate all the suggestions & directions, but I do not have any cylinder heads to either bore one out for a torque plate or even use one for a pattern, so I am out there asking for a blueprint to make one. Just a side bar question, if I find a single cylinder head (left or right) would that one head work for both sides as a boring / torque plate or do I need left & right examples? I guess I could search Craigs list around here for one.

I asked for a print a few years ago and got little to no response. I was hoping to find an old Ford drawing similar to the one of the front of the block I've seen several places. I'm going to need one for a 21 stud block shortly so I'm deciding what to do. I CMMed a 21 stud Victor gacket and a 24 stud gasket and entered the data into CAD to get their geometry. Here's a photo of the two laid together.blue is 21 stud, red is 24.


I could mill cavities in a stock head and use that, might still do that. To use it for pressure testing it would be nice to have the complete combustion chamber open in order to see the ports and valve seat area, which a round hole wouldn't allow. Milling the entire chamber out of a stock iron head might make it pretty flexible, I wouldn't know until it was done. It would certainly be the cheapest way.

I sent DXF files to a water jet firm for some quotes. Here's what I got back -
1 Gasket plate, 1/2" 6061 Aluminum
1 /EA $124.57 10 /EA $71.66

2 Gasket plate, 1/2" 1018 Flat bar
1 /EA $305.14
10 /EA $99.53

^^^^^ I thought 1/2" or less would be handiest for pressure testing.


21_STUD-PLATE-1.53 Gasket plate, 1 1/2" 6061 Aluminum W/Holes
1 /EA $313.17 10 /EA $252.63

^^^^^1-1/2 Material would be close to the average thickness of a stock head. Would require washer/spacers under the long studs and would require counterboring for the short studs.

21_STUD-PLATE-1.54 Gasket plate, 1 1/2" 6061 Aluminum W/out Holes
1 /EA $252.67 10 /EA $194.88

^^^^^ This is the thick plate with no holes, to allow drilling the holes instead of waterjetting them


21_STUD-PLATE-RUBBER 5 Gasket plate, 1/8" Neoprene rubber
1 /EA $109.21
10 /EA $34.08


21_STUD-PLATE-RUBBER 6 Gasket plate, 3/16" Neoprene rubber
1 /EA $124.70
10 /EA $39.16

^^^^^ Rubber gaskets cut to the same shape for pressure testing. For $124 for one I'll cut my own.

Waterjet tolerance on the 1/2 plate is about +/- .005, which would give bolt holes up to .020 oversize, which would be OK. On 1.5" plate it would be +/- .015 which is why I asked for a quote w/o the holes.

There is discussion by race engine builders about ideal block plates, thickness, material, etc. to duplicate the effect of the head being attached, that's why I asked for aluminum and steel and 2 thicknesses. I priced a piece of Durabar grade 40 cast iron bar, it costs over $300 just for the bar so I stopped there. This makes the BHJ plates look like a bargain. Steel would stand up better to repeated torquing than aluminum.

I'm not concerned about stressing the block "straight" with the heads because the flathead heads are so thin, I think they will conform to the block. I just need to pull on the studs/bolts to distort the cylinder bores the same as they will be when the heads are on and torqued. So for that I think an aluminum plate in 1/2 to 3/4 thickness will be plenty.

It doesn't look practical to make a combined plate for honing, because the 21 stud pattern interferes with larger bore sizes possible in a 24 stud block. You could make pressure test plates with both, and in that case you could go even thinner, like maybe 1/4".

This geometry is reverse engineered from a gasket, so we can't know how close to correct it is to the OEM locations - that would require a Ford drawing. I think it's close enough to use for this. I found that both gaskets had 2 holes smaller than the rest, I imagine those were to locate the gasket on those 2 studs and the rest are larger to make it easier to install over the studs.

A nearby friend has his own 24 stud plates in both aluminum and steel, now that he has the aluminum plate he doesn't use the steel one just because the aluminum plate is so much easier to handle. On that subject I think I'd add material on the ends and cut a hand hold in each end to make them easier to install and remove.

These prices don't save me much over whacking my own out of plate on a CNC mill in my own shop so I'm probably going to just mill my own then I have control over the whole process. Roughing a thick one out on a waterjet then drilling it on a CNC would cost about the same as milling it complete so that's out

I'm willing to share the geometry and the contact info for the local waterjet firm, they are very competitive on other plasma and lazer work I've had them do, but shipping these any distance would add enough to the cost that you might be better off doing it locally. This firm said the programming for a 2D part like this is only about $25 and that's added into these quotes in the part prices. Maybe a group buy is a possibility but I'm not the guy to orchestrate that.

[flatjack9]

I'll give you one if you want to pay shipping. In fact I can give you 2. By chance do you go to the swap meet in Jefferson, Wi. at the end of April?

[outlaw]

Why can't you use a head gasket to make a pattern from"

[Brian]

I made my own in both 21 and 24 stud configuration , able to accommodate up to 3 7/16" bore. Pity I'm in New Zealand...
Can't upload pictures, dunno why?

[flatheadmurre]

Originally Posted by Brian

I made my own in both 21 and 24 stud configuration , able to accommodate up to 3 7/16" bore. Pity I'm in New Zealand...
Can't upload pictures, dunno why?

The Site has become more sensitive to picture size after the update...try reducing the size of pics.

[Brian]

Thanks Murre, we'll try this;

[outlaw]

So since we are on this subject, is a aluminum torque plate ok or should it be made out of steel? Would aluminum be strong enough to stress the block correctly? What should the thickness be for either material ?

[JSeery]

OK, first some heads are aluminum! But the real issue is the thickness of the torque plate. A 3 inch aluminum plate is going to be stiffer than a 1/4 inch steel plate. It is all going to depend on the material you use and the relative stiffness.

[steve hackel]

Although not my rebuilder, I lnow someone that does CNC water jet cutting , so would this be the same process and also accurate enough for this application? I probably do not know enough to ask the right questions.....

[John R]

Just as a point of reference, deck plates for flatheads are available from at least two sources:
BHJ Products: http://www.bhjproducts.com/
CCA Racing Products: https://ccaracing.com/

[Shoebox]

John R,
Thanks for that info, CCA is not far from me, good to know. A related torque plate question, must a torque plate be the EXACT size of the intended bore? I ask because I would consider buying a plate if I could have it the largest I might ever need, even if the current build is slightly smaller.

[flatheadmurre]

Heads aren´t made to bore size so why would a hone plate...it´s not that sensitive.
It´s more about the force on the headstud/bolt deforming the bore.