Get a proper valve job done, remove a shim from the head gasket, get ignition advancer, tune.

You can also get a G model jug and bore it out to accept RR pistons and do a small big bore.

Since you are in the UK, you can also do A1P stuff and make it a 636.

Unless you have a bag full of money, that is really all you can do.

 

Get a proper valve job done, remove a shim from the head gasket, get ignition advancer, tune.

Following up on the remove a shim from the headgasket..I know it will increase the compression ratio but won't it cause other problems?

Such as, since it's thinner AND a higher compression isn't it more likely to "blow" the head gasket? Would it need a slightly higher torque rating on the headbolts to counter this possibility?

I'm assuming you would have to take a measurement of the shim that you took off, and subtract the valve clearances accordingly? :O

Just a curious person haha

 

You are removing less than .015" shim. You have nothing to worry about.

 

RJ, I think you have that a little wrong.

He is referring to valve to piston clearance. If the valve makes contact with the piston, it is catastrophic.

There is no adjustment for that.

Again, removing one shim from the head gasket will not cause any valve to piston clearance issues.

 

Here I was, thinking I said just that, LOL.

We both agree, a shim in a head gasket is only going to lower the deck height 10 or 20 thousandths of an inch, after the head gasket is compressed.

The shim under bucket adjustment is purely for valve lash. When the OP made it sound like that distance has something to do with the head to cylinder deck spacing -- that's not what is meant to be affected, although it does play an incredibly small part in the relationship between the valve's head, and the piston. -- as you said, inconsequential.

Mis-timed cams would have a much more serious effect.

 

Well, a closer head does create cam timing issues. Thinner gaskets and tighter squish is the very reason why adjustable cam gears were invented.

If you up the compression enough by removing gaskets and decking the jugs/head, you will need to get aftermarket cam gears. They do make them, but they are hard to find. The only people I know that can get them for a J model is KWS MOtorsports in Charleston, SC. Kevin has some serious insider connections, and for good reason.