• Hi Guest! Being a Paying Supporter is NOT a requirement to participate at BCF. However, subscribing will help ensure we can continue to serve the LBC community for years to come. If you enjoy BCF and find our forum a useful resource...Please consider supporting us by **Upgrading**
    (PS: Subscribers don't see this banner)

TR2/3/3A TR3 Head Gasket Questions Con't


Jedi Hopeful
Country flag
Here I go with some more questions.... I appreciate the indulgence of my seemingly endless curiosity about what I should do with my LBC :eek:

In the attached pictures you can see a composition gasket and a copper gasket placed on top of the head that I positioned on my work bench and a picture of the valves inside the cylinder head. The head was previously "grounded" on these sides to improve gas flow, I will assume, and the head was milled for higher compression (you may recall my earlier posts), if you look where I have numbered the cylinders and drawn some arrows on the blue tape covering the valves this is where the lip of the gasket is slightly "proud" i.e. wider than the bore of the valve cylinder chamber by maybe .02 to .01. and there is a bit of a sharp edge on the opposite side of the arrows in each chamber.

Since I am not an expert on engines I'm wondering if the "hanging edge" of the gasket will this cause a problem or at least be somewhat obtrusive to air flow inside the combustion chambers and maybe cause premature failure? The composition gasket looks to be pretty nice with the silicon seals, the rims of steel appear to fit snug on top of each of the cylinders, over all it seems like a pretty nice fit. The copper gasket is .032 thick and the cylinder holes are not exactly perfectly round and there is no "crush factor" when the copper gasket is installed.

My questions: The roundness of the steel gaskets (composition gasket) sitting on top of the cylinders are definatly not the same roundness of the valve chambers. Would the lip of the gasket that is “hanging” be prone to fail or be disruptive to the operation of the valves? There's not a lot present but there is enough to be detectable plus I am thinking I might file the valve chamber more to eliminate all sharp edges something that Roger Williams wrote about in his book "Enthusiast's Restoration Manual (pg 94) but I would not grind back more than the size of the gasket my only issue is where it was done by the PO. However, if I use a solid copper gasket I can file the gasket a little to fit the size of the valve chamber better and seemingly a better combustion chamber that is void of any obtrusions from the gasket while maintaining a good seal from the copper on top of the cylinder sleeves. There's a fair amount of questions about the reliability of a solid copper gasket that is used by some racers but Charley seems to have had some good experience. The composition gasket has had some good reviews by others so for me it is going to come down to deciding which gasket installation would provide the best performance (street application) and reliability. Any Thoughts?

TR3 Valves in Head (3).jpg TR3 Valves in Head.jpgTR3 Valves in Head (3).jpg


  • TR3 Valves in Head w cpr gsk (2).jpg
    TR3 Valves in Head w cpr gsk (2).jpg
    37.3 KB · Views: 47


Jedi Hopeful
Country flag
Did the water and oil mix? Or did the engine get hot while idling? What kind of fan do you have?

The engine took on water while at the body shop. Car was left in weather and I think the water got in from the valve cover that did not have a gasket on it, who knew the body shop was going to treat my newly rebuild motor this way. I took the head off to remove the water from the tappets, clean oil pan etc. then I got to looking more carefully at what I had created with the head rebuild and some new found knowledge regarding TR3 engines ta da the questions started coming.... Head was from a retired racer who advised me the head was a "good one" and I bought it from him and proceed to have it rebuilt by a local machine shop. The engine has not run since it was rebuilt in 2012 I have an electric fan and I put in a aluminum radiator and converted to an alternator.

The head is going back on this weekend I just need to make a decision on which gasket to use and how I am going to put everything back together.


Great Pumpkin - R.I.P
Tough call, IMO. You've found exactly the reason that many racers use solid head gaskets, so they can trim them back to clear the combustion chamber mods. Anything that hangs out in the chamber, especially the thin cladding on the composite gasket, is likely to cause problems. So my inclination would be to either buy a larger composition gasket (assuming that isn't already the "89mm" gasket) or go with the solid copper. Sometimes they work out OK.
Similar threads
Thread starter Title Forum Replies Date
G TR2/3/3A TR3/TR4 Cylinder Head Gasket SElection Triumph 2
Lukens TR2/3/3A TR3 blown head gasket? Triumph 39
RedTR3 TR2/3/3A TR3 Head Gasket [Again] Triumph 4
RedTR3 TR2/3/3A TR3 Head Gasket Triumph 6
S TR2/3/3A TR3 Copper Head Gasket -- quick questions Triumph 8
S TR2/3/3A TR3 head is off -- awaiting head gasket Triumph 9
S TR2/3/3A Uggh! TR3 head gasket leak!!! Triumph 9
Got_All_4 TR2/3/3A Blown head gasket TR3 what to do next? Triumph 16
martx-5 TR2/3/3A TR3 Head Gasket Triumph 16
Marvin Gruber TR4/4A TR3/4 head thickness Triumph 7
M TR2/3/3A Tr3 Head Rebuild Triumph 3
Got_All_4 TR2/3/3A The bolt on the back of the tr3 head Triumph 4
luke44 TR2/3/3A TR3 Brass Heater Valve to Head - How to treat threads, if at all? Triumph 6
Kleykamp TR2/3/3A 1961 TR3 control head. Triumph 5
K TR2/3/3A Can porting a TR3 Cylinder head be a DIY job? Triumph 6
Scotsman TR2/3/3A Signal switch on TR3 Horn Control Head not canceling Triumph 20
C TR2/3/3A TR3 Low Port vs High Port Head Triumph 10
O TR2/3/3A TR3 Steering Wheel Hub / Control Head Triumph 1
O TR2/3/3A TR3 Control Head Install Triumph 6
H TR2/3/3A TR3 head /cam Triumph 4
K TR3/4 Cylinder head temperatures? Racing 1
O TR2/3/3A TR3 Control Head Stator Tube Install Triumph 5
tinman58 TR2/3/3A Removing head studs TR3 Triumph 15
K TR2/3/3A The Aluminum Plug in the Cylinder Head ?[Again]TR3 Triumph 2
S TR2/3/3A tr3 head light switch Triumph 3
K TR2/3/3A Head bolt torque TR3 Triumph 3
H TR2/3/3A TR3 -- Pull the head "while I'm in there . . ." Triumph 9
K TR2/3/3A Internal view of a tr3 control head Triumph 7
mountainman TR2/3/3A TR3 Bright Head Lights Triumph 3
mountainman TR2/3/3A TR3 Control Head Wiring Triumph 11
Marvin Gruber TR2/3/3A TR3/4 cylinder head differences Triumph 3
newmexTR3 TR2/3/3A tr3 head rear oil leak Triumph 9
T TR2/3/3A TR3 head core plug [freeze plug] Triumph 6
A TR2/3/3A TR3 head welding Triumph 4
Tinkerman TR2/3/3A TR3 Oil filter head, long stud? Triumph 2
TR4nut TR4/4A Aluminum plug in TR3-4A cylinder head? Triumph 4
F TR2/3/3A TR3 Turn Signal/Horn control head Triumph 4
A TR2/3/3A TR3/4 head crack, can it be welded Triumph 11
K TR2/3/3A Torqing the head again?....rebuilt motor... TR3 Triumph 4
A TR4/4A TR3 / TR4 head crack repair Triumph 3
J TR2/3/3A TR3 control head internal pictures? Triumph 11
C TR2/3/3A TR3 Head Work Triumph 2
C TR2/3/3A TR3 Head Triumph 3
S TR2/3/3A head bolts on a tr3 Triumph 5
MGTF1250Dave TR2/3/3A TR3 Control Head Triumph 4
D TR2/3/3A Control Head [TR3] Rebuild Triumph 2
bluemiata90 TR2/3/3A TR3 Horn,control head and stator tube removel Triumph 9
MGTF1250Dave TR2/3/3A TR3 Control Head Help Triumph 9
E TR2/3/3A TR3 Cylinder Head Lubrication Triumph 11
J TR2/3/3A What size speedi-sleeve needed for pinion seal on a TR3? Triumph 0

Similar threads