TQ plate FH

3

3W Hank

Well-known member
About TQ plate on the FH.

I has a Merc 41 block ported back in the days I bought in LA, but it had a crack from exhaust port to the cylinder ( but very nice port work ) and the fellow sold had it for over 30 years and history it was from a racer and brought it back the the machine shop in Burbank area. I guess could been 50’s or 60’s and it’s 1/8” over std.
When I bought it has been sonic tested and it was over 0.25” wall ( no one believe that ) but pressuare test showed a port hole in 1 cylinder so I bought a 3.5” OD sleeve.
Sleeve its now mounted and idea is hone it equal size and order custom pistons from Ross.
That will be a hair over 1/8” over std ( or .125" )
Block had been in hot tank twice and also laser cleaned.

-So the question is before hone, do this block’s like TQ plate or how is bolts effects cylinders ?
I can make a TQ plate cant find blue prints of bolts.
 
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Cylinder distortion can be eliminated when A torque plate is used on a Ford flathead block. The bolts holes located along the outer radius of the bores in the 3,5,7and 9 o'clock positions can distort especially when the bore size has been increased to .125 and above. That also includes when a sleeve has been installed.
Ronnieroadster
 
I’m with Ronnie above on this. I use my torque plate on all 24 stud flatheads I build. I need to get one for my 21 stud builds. Mine is also cut out around valves like head gasket so I can use it to pressure test.
 
Definition of a Torque Plate

A torque plate is a thick metal plate that is bolted to an engine block during the machining process to simulate the stress that the block will experience when the cylinder head is attached. This helps ensure that the cylinder walls are perfectly round and straight, improving engine performance and durability.

A torque plate is a specialized tool used in engine building. It is a flat plate that is bolted to the engine block during the machining process. The purpose of the torque plate is to simulate the forces that the engine head will apply when the engine is fully assembled.





BHJ_HoningPlate_RModel_Auminum.jpg
 
Thanks.
Any information where a blueprint can be found.
I rather dont like to punch via a head and then manually drill, its easy one need several off. I has done it in my past, but then I bought BHJ's.
Best is had the measures and run it in a CNC.
I do has 50 mm aluminium plates.
 
I made one from an old head that a valve went through the combustion chamber. Made a template/guide from 2" thick hardwood based on a gasket. Holesaw, and patients.
 

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SO, question for Ronnie & Tony


When using a "torque plate" do you torque it to the block just like a head to duplicate a head being on the block (So to speak)???
 
rockfla said:
SO, question for Ronnie & Tony


When using a "torque plate" do you torque it to the block just like a head to duplicate a head being on the block (So to speak)???
Click to expand...

Yes that's exactly what we do torque to the amount desired aluminum head would be less than a stock iron head. Between the torque plate and the block I used a solid copper head gasket. The gasket is used to represent as close as possible the distortion produced between the two surfaces.

My torque plate was machined from a 1 inch thick piece of steel plate that was ground perfectly flat prior to drilling the 24 bolt holes and the cylinder bores which are 3-3/8 diameter on mine also we did not cut out the valve area. Ronnieroadster
 
A technical question for Ronnie. Why did you not cut out the valve area? It would seem that if it were cut out, it would more likely duplicate the deformations and stresses etc. of a stock head being torqued. I realize I am probably splitting hairs, but I'm just curious.

I realize that cutting them out probably wouldn't change a thing.
 
Same procedure for me as Ronnie.
Here is my plate.
 

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I cant see the distorotion if round or open up chambers, what the effect we like to see is the drag on bolts as on some engines its a problem, some not.
In the 80’s we was into heat hone ( with TQ plates on ) but I has not heard about that for decades now.
Then in a running engine its hear/waterflow etc but main thing I call for is drag on bolts if it get any changes.
-If I could get those blueprints.
 
Since the critical area of distortion is the location of the holes around the cylinder bores. These holes are extremely close to the bore so my torque plate design with just the bore holes was a simple design that works fine. Note the holes around bores on the 21 stud block is even worse.

I already have a very good test fixture I use when pressure testing the flathead blocks for cracks. Any additional material removed to duplicate the valve pocket area on this plate would have been a waste of time.
Ronnieroadster
 
There are no pictures of the TQ ( design ) on both BHJ and CCA but both are + 400.
I might get a BHJ, just to save up time.
 

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