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General Chat About Exhaust, Cylinder Heads, Fuel Systems And Intake

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sidecar
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Post by sidecar »

What you are going through is the exact reason that I gave up with shims! They are a total PITA!

In reality the way that the lifters work means that they will work over hugepre-load range, this was done by design so that Rover/Buick did not have to mess about when bolting thousands of engines together.

But like I said before they did not have to worry about pump up causing a valve to piston clearance issue.

If number 8 has too little clearance then you don't have much choice other then to close up the clearance on the other lifters.

Quite often you can fit adjustable pushrods without opening out the guide holes, the big issue with then is that they are quite expensive!

You can quit


Automania
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Post by Automania »

sidecar wrote:What you are going through is the exact reason that I gave up with shims! They are a total PITA!

In reality the way that the lifters work means that they will work over hugepre-load range, this was done by design so that Rover/Buick did not have to mess about when bolting thousands of engines together.

But like I said before they did not have to worry about pump up causing a valve to piston clearance issue.

If number 8 has too little clearance then you don't have much choice other then to close up the clearance on the other lifters.

Quite often you can fit adjustable pushrods without opening out the guide holes, the big issue with then is that they are quite expensive!

You can quit
Haha yep pita is an understatement.

The standard rods are quite close so can't imagine adjustable ones fitting with out work.

My heads spinning with this now :shock:
Anyway I'll go and try some more shims in and see what happens, also I've got some more rods I'll just see if there's one a bit longer (fingers crossed)

Thanks again
Automania
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Post by Automania »

Ok think I may have sorted it, I tried another rod from another engine, didn't make any difference, so I thought, why don't I swap the lifter with another that has a bigger clearance so I swapped it with no.2, and I'm now getting between 0.020 and 0.027 on no.8, I'm just having a brew then going to try swapping some others around to get no.9 and 14 down a little, fingers crossed.
sidecar
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Post by sidecar »

It's good to see that you are putting some effort into building your engine, many people just bung them to together, yes they will probably run OK but in my book it is better to do it right and just once! :P
Automania
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Post by Automania »

sidecar wrote:It's good to see that you are putting some effort into building your engine, many people just bung them to together, yes they will probably run OK but in my book it is better to do it right and just once! :P
Thanks, I'm no perfectionist far from it but I have turned a bit anal about this build (well the bits I've done), even gone as far as painting the rocker covers etc, which is a bit of a joke when you see the rest of the car!

Obviously I'd still be well stuck if it wasn't for the fantastic people one here. :D
Wilts289
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Post by Wilts289 »

I alway thought it was a no-no to change rods around as each rod bedded itself into its mating rocker.
Automania
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Post by Automania »

Wilts289 wrote:I alway thought it was a no-no to change rods around as each rod bedded itself into its mating rocker.
Probably but I had a new set of rockers too. Probably should have fitted new pushrods I never really thought about it till later
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