How much do lifters expand when engine running? Yella Terra rockers hitting the covers

[e.drooy]

Hi All
My name is Erik and Im in the process of building/modifying my MGB V8. And Ive run into a little problem with my new Yella Terra rockers...., the covers dont fit anymore. So the plan is to make a layer between the covers and cylinder head to lift the cover clear of the rockers. The question is how much should i raise the covers to stay clear of the rockers when the engine is running?

Thanks so much for help! Will soon post pictures of the project

[mgb260]

There are valve cover spacers you can buy on Ebay for that purpose.

https://www.ebay.com/sch/i.html?_from=R40&_trksid=p2499334.m570.l1313&_nkw=rover+v8+valve+cover+spacers&_sacat=6000

[roverman]

OR you can go with 340 Buick = more rocker room and they look different.    Art.

[e.drooy]

hmm, the idea is to go for 3D printing, the same as for some other parts... no need to lift the covers more than strictly necessary because the thor manifold is in the way of raising the covers.

[RoverP6B]

You can also use Offenhausers valve covers as these are a bit taller than stock, I'm also using Yella Terras. Graham

[Robrover]

I fitted a custom metal spacer between my 4.6 block and P6B covers to clear the YT roller rockers. You may also be able to glue two cork rocker cover gaskets together to achieve enough clearance, though the spacer or a taller other make cover is a better option.

[rficalora]

Hydraulic lifters have a total travel of about 0.200.  So, start by measuring the gap between the cover and cylinder head, subtract the gasket thickness, and add 0.200.  That plus a few thousands clearance would be the absolute minimum.  But, personally, I would want at least 1/4" or more clearance.  That way I wouldn't have to worry about differences in gasket thicknesses that might get used over the years.

Also, if your covers aren't baffled, when the rockers are that close, you'll need to consider how to keep oil from getting sucked into your PCV &/or quickly saturating the breather.

For reference, this is a picture of my cover which has about 1/4" clearance to the under side of the cover.  They are not baffled.


If you can 3D print, why not just print yourself a few sets of washers at