Hydraulic lifters: How much play can they compensate?

Hello,

I bought a new (used) camshaft that has been reground to achieve more valve lift.

Now, while measuring the re-ground camshaft, I noticed that the base circle of the camshaft is 3mm smaller than that of the original camshaft.

A tuner claims that the hydros cannot possibly compensate for a 3 mm difference.
The person who sold me the camshaft says it wouldn't be a problem (of course ).

I could test it myself, but I'd rather save some time and ask here first. Maybe someone can tell me how much pressure (in mm) a Hydros Max can compensate for?

Vehicle: Volkswagen Golf 3 AFN.

Thank you in advance.

Regards,
DJ.

Okay, I can't tell you the exact value, but 3mm is definitely too much; it's best to return that thing quickly.

Apart from the dimensional changes, I doubt that the hardening of the camshaft has been maintained... If it was supposed to be re-hardened (?), then achieving the precisely correct level of hardness would likely also be difficult.

What the Hydros can compensate for becomes apparent when you install new Hydros with the head disassembled. Initially, all valves are open, even where the NW is set to "closed." That's why there's a half-hour waiting period before starting (show me someone who can actually get the engine running again within that time ).

"3mm is definitely a lot, especially because you generally don't want to run the hydraulics at their maximum capacity. In that case, they wouldn't be able to compensate for anything else."

The question of whether this modification is actually worthwhile has already been discussed here.

What the Hydros can compensate for becomes apparent when you install new Hydros with a worn-out head. Initially, all valves remain open, even where the NW (needle valve) is set to 'closed.' That's why there's a half-hour waiting period before starting the engine (show me someone who can actually get the engine running again within that time ).

'3mm is definitely a lot, especially because you generally don't want to run the hydraulics at their maximum capacity. In that case, they wouldn't be able to compensate for anything else.'

Whether the modification is actually useful has already been described here...


I have the new Hydros right here in front of me, so I think they can handle an extra 3mm.
What do you mean by whether the 'modification is even worthwhile' – are you referring to the polished camshaft?

dj1 wrote:

Here are the new hydrants I have in front of me, so I think they can handle an additional 3mm. 2) What do you mean by whether the "

modification is even worthwhile" - the ground camshaft?}

Here's the translation:

"The new lifters are installed. You could install a hydraulic lifter and set the cam lobe to its baseline position. Then, the valve spring should need a little preload. In other words, the valve keepers shouldn't be fully seated; instead, the lifter should be slightly compressed, or the valve should be open a bit. I hope you understand what I mean. Pay attention to the top dead center (TDC) position, so you don't press a valve onto the piston. I have no idea how much clearance you have there."
2) Using the search function, I found, among other things, this post:
Okay, I understand. Please provide the German text you want me to translate into English. I will only provide the translation.