Head gasket advice from you clever chaps!

[mikeinatruck]

I was going to rebuild my Land Rover 3.5 high compression engine, but after removing the heads it seemed to be in pretty good condition with all the valves thes right colour which suprised me and the bores seem good too.

Thing is it had the tin plate gaskets for the HC as I use it for off roading and thats all, I was wondering if using the composite head gaskets would drop my compression much.? It spends most of its time in low box and sensible revs but hill climbs mean some higher revs

Is there anything to gain? and is a lower compression better than a higher one for my purpose?

[sidecar]

This is just my opinion but the composites are more reliable than the tin gaskets. Look very carefully at the old tin gaskets, are there any brown marks running out from the bore holes out towards the valley area?

If you just fit the composites they will lower the compression by about 0.5 of a ratio and this will cause a small loss of power across the rev range. It does not cost much to have the heads skimmed to get the CR backup to what you want.

If you just fitted the composites without skimming the heads you might find that the lifter pre-load is not right and will not be easy to sort out as the effect would be that the pushrods are too short.

The other thing to do whatever gasket you go for is to NOT fit the outer head bolts (The ones near the plugs). They actually help the gasket leak!

To sum up I'd go for composites, a head skim, and a set of pre-load shims from Real Steel. (And allow many hours to set the pre-load!)

If you've got some dosh spare then go for adjustable pushrods so that you can get each lifter pre-load spot on.

HTH,

Pete

[mikeinatruck]

Hmmmm... more work than i was planning. I think i'll just refit new tin gaskets, as they seemed good when i took them off. I was only going to torque the outer head bolts to 20nm anyway. I dont want mud going into the threads its just hassle.

I might put in new lifters though as one or two where starting to get a bit ticky,. Next year though its getting done properly, honest

[sidecar]

Hmmmm... more work than i was planning. I think i'll just refit new tin gaskets, as they seemed good when i took them off. I was only going to torque the outer head bolts to 20nm anyway. I dont want mud going into the threads its just hassle.

I might put in new lifters though as one or two where starting to get a bit ticky,. Next year though its getting done properly, honest

Fitting new lifters on an old cam may not be a good idea, the cam and the lifter wear in such a way that a new lifter on a worn cam could have a tough time. I'm sure that others will be along with more comments.

Good luck with whatever you decide to do.

Regards,

Pete

[katanaman]

don't do it unless you renew the cam as well.

[mgbv8]

To be honest. I didnt notice any difference on my 3500 when I fitted comp gaskets. It seemed to drive the same and gave the same ET's on the drag strip.?