Single valve Springs 2 1/4 Petrol

[northerndefender]

I am doing some head work on my early 2a petrol.  The head originally had the double valve springs with a smaller one inside the bigger one.  They are no longer available so I got the single version ERR4640.  Should I be concerned with the bottom of the valve moving about as, without the inner spring, there is less keeping it in place?

[Red90]

Later engines use the single spring and there was nothing added to retain the bottom.

[jeffrey]

I had converted my series 2A head to an unleaded where there is only one valve spring for each valve.  However from the parts book I have you are correct, in that the diesel and the petrol models had an inner and outer spring. https://www.johncraddockltd.co.uk/502904-valve-spring-inner-and-outer-exhaust-2-6-litre.html

I see that Craddock sells the inner and outer springs, but they are not cheap and are 26pounds each.  I also saw a couple on e bay the inner and outer that someone was selling.  So it looks like they are still around.  Hope this is helpful.

[northerndefender]

Hi John and Jeffrey.

Thanks for your replies.  According to Turner Engineering in the UK, the double springs have been not stocked by Land rover since the mid 80's.  I have put the head on this morning and I don't predict any issues ::)

[Matt H]

Dual valve springs are usually associated with performance engines and a more aggressive cam profile. It helps prevent valve float at higher rpm.

However we are talking old Land Rovers and old engineering here. Long before any performance applications dual springs were often used as an alternative to a tall, heavier single spring. Spring technology at the time was such that a single, light weight spring of the required rate was not available. By using two the engineering boffins could reduce the overall valve train package height while achieving the required spring rate.

Valve spring technology has progressed much and now valve springs of the required rate and height are available in a single spring.

Historically important engines should be built as original as that is part of the interest.
But for most of us it simply doesn't matter. After all it's not like your going to whip the valve cover off at the local show & shine and proudly display your double valve springs!

[jeffrey]

Well said Matt.........