UL head gaskets

[thepigstye]

Id like to hear others opinions on what type of head gasket material is preferred choice for a 74" flathead, 3 bar heads, hot cams, etc. I see they come in copper, fiber/steel, blue teflon and James fiber with the bead of sealer on them.

[kitabel]

The one that puts the piston .035" from the head @ TDC.

[flatboy1950]

If you have ally heads , use copper gaskets to help as much as possible to transfer the heat from the exhaust valve area & exhaust port area up to the head & then out into the air flow. Let the heat go !! Blowin' in the wind !!
Flatboy.

[chuckthebeatertruck]

it truly depends on the state of your head bolts AND their threads.

Copper head gaskets tend to "creep" around the exhaust area because the temperature gradiant seen by the head varies so much from end to end. If your bolts and threads are in excellent shape you'll have no issues. If a thread is slightly pulled, over time the bolts will lose tension and the gasket burns.

In this regard, fibre or teflon gaskets give less trouble.

All that said, with careful assembly and a watchful eye; either type of gasket works well.

[thepigstye]

head bolts and washers are new Colony stuff. Rear cylinder is NOS, front cylinder is still stndard bore, so it's in good shape. Got a set of 3 bar iron heads but thinking about one of those sets of ULR aluminum heads. Has any one here ever looked at a set in hand?

[chuckthebeatertruck]

Double check your washers.

The colony head bolts are made from 4140 -- the washers have had a tendency to be much softer than the bolts -- creating a distortion when torqued.

Doesn't mean there is a problem -- it means you need to pay close attention to them if they are still soft (I haven't bought colony washers in several years and don't know the current composition). Basically, several retorques in the first 500 miles. Retorque is not loosen and reset -- it is pull the bolt tight until there is no more creep. I find a good 9 inch wrench to be the best here -- not a torque wrench. Just my two cents.

[chuckthebeatertruck]

Yes, several members have used the finnish heads you reference. I've heard nothing but good about them, but haven't used them myself.

[thepigstye]

I dont got a hardness tester, but I can check with Mark at Colony and see if the current head bolt washers are hardened

[kitabel]

You may be able to find NOS WLA domed washers.
I had studs made, 7/16-16 & 7/16/20

[thepigstye]

I have a bunch of NOS 45 head bolt washers, just dont know if I have 18

[chuckthebeatertruck]

you don’t need a hardness tester.

take one of the washers and run everything down tight. let it sit a few hours and give the bolt a check to see if it creeped. if yes, tighten and repeat till it doesn’t move after a couple hours. then, undo and look at the washer. if it is marked with the bolt pattern or dimpled where it abuts the through hole, you “may” have soft washers.

This is one of the places you want hard washers that do not distort.

Flatty cylinder heads run hot and see huge temperature variations. the better our surfaces, threads, and hardware the more reliable the seal regardless of gasket composition.

[kitabel]

Take a close look at the deck surface of the cylinders. Is the top thread a bit rough? Can you feel it with your fingernail?
Counter-sink the top thread very lightly so that the first .010" is clean.

[Frankenstein]

The ULR heads are an excellent investment, quality is excellent, AND they extend engine life. The reshaped combustion chamber eliminates a hot spot in the combustion process that occurs right where pistons disintegrate when these motors aren't babied. It's where the piston comes closest to the intake valve.
I've had mine nearly 10 years now, highly recommend them.
If you look at the popular flathead engines out there today, Kohler, B&S, etc, you don't see any with a combustion chamber shape like the BTSV. I think Sir Harry missed it on that one, if he actually was consulted on that design.
Bottom line, first dollars you spend on your rebuild, buy ULR heads
DD

[RooDog]

The ULR heads are an excellent investment, quality is excellent, AND they extend engine life. The reshaped combustion chamber eliminates a hot spot in the combustion process that occurs right where pistons disintegrate when these motors aren't babied. It's where the piston comes closest to the intake valve.
I've had mine nearly 10 years now, highly recommend them.
If you look at the popular flathead engines out there today, Kohler, B&S, etc, you don't see any with a combustion chamber shape like the BTSV. I think Sir Harry missed it on that one, if he actually was consulted on that design.
Bottom line, first dollars you spend on your rebuild, buy ULR heads
DD

Statement, not a question: I wonder what they cost, delivered to US address, today....
....RooDog....

[kitabel]

Highly developed Kohler SV chamber, note the similarities to KR