Thread: 14 Bolt Head Gasket

Can I use a 3.9 litre 14 bolt steel shim head gasket on a 3.9 litre with 10 bolt block and heads? Part number ETC7819.

Can I use a 3.9 litre 14 bolt steel shim head gasket on a 3.9 litre with 10 bolt block and heads? Part number ETC7819.

I take it the 10 bolt head originally had a composite gasket? If they had steel gaskets ignore the rest as it doesn't matter.( i cannot remember the fine detail of when steel went to composite)

if so you can use a 14 bolt shim gasket to give a higher compression ratio , but you may have to shim the rocker pedestals to regain the correct minimum preload.

The composite heads have a 28CC combustion chamber equivalent to milling 40thou from a shim gasket head.

I have done the opposite after milling a 14bolt steel gasket head by 40 thou with no problems. I cannot imagine the extra holes in the gasket causing a problem as the other bolt positions are identical.

The extra bolts were deleted as LR found that the 14bolt heads "jacked" over time and caused a combustion leak outwards. Later instructions for 14 bolt heads were to only do the top row up to a notional 20foot pounds or whatever.

However the steel gaskets require the block and head surfaces to be perfect. Mine used to leak from the ends as presumably the block relaxed over time and had a slight bow.
Regards PhilipA