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whats the difference in stock preload, so im guessing you need different length pushrods for the newer version?

I must have been lucky with my VS, never had any lifter issues or noises for the 380km it did, still have to crack it open sometime and see what the wear is like on it!

Our old VS had no noticeable wear on the cam over 230,000km. Shame I threw it away as I need a core for a regrind now, on the other hand it had bad wear in the rocker push rod cups.

edit: the wear was bad enough that some rockers had virtually no pre-load and no doubt the source of valve train noise. We did a quick measure on the crank and that too was within spec, close to maximum but still within spec and no major marks on any of the journals. Should have kept that engine as a spare.

The1 wrote:whats the difference in stock preload, so im guessing you need different length pushrods for the newer version?

I must have been lucky with my VS, never had any lifter issues or noises for the 380km it did, still have to crack it open sometime and see what the wear is like on it!

The wear will still be there. The noise comes from the hydraulics themselves shitting itself, not so much the wear.

I got this table for the OEM lifters.

Will have to check these lifters it was from a VT not sure what year, the wagon's a 2002, im guessing the cam changed as i dont recall the pushrods or rockers ever changing?

It's quite possible they could of used the older gen of lifters to the end of production. I don't recall ever seeing an ecotec with shorter lifter travel but then again I only messed around with VS and VT motors. I did have a VY one but never looked at them.

Mates VY L67 still had the stock style lifters, used OE lifters when he put in his cam but one went noisy so now he's putting in the ZZP lifters which have the reduced pre-load. If I ever do lifters it'll be the LS7 type.

ZZP ones are the last one on that list ending in 490. They are good lifters, mine are quiet as and sure can take a beating.

My next engine will use the custom set of Johnson lifters I got made. They only have a travel of less than 2mm, preload of 35 thou alloy engines and 20 thou for iron. Anti bleed and anti pump too.

the 490's are the LS7, my mate is using the custom ZZP lifters which are different again (or so they say and charge a bit more).

Apparently there is another PN more specific to the LS7, 12499225 , the 490 was used in other engines as well not just the LS7 but are still commonly refereed to LS7 lifters anyway. My understanding is the 490 was the early LS7 lifter before they went to the 12499225 ones?

Not sure vlad, Here's the 2 lifters, I can't tell the difference measured all parts with calipers, even pushed inside core all way down in without spring and both are 10.5mm so same bore depth.

Bottom one is from the VX 2002 engine VA209115 and top is from VT SC I think 1997? Engine VS723627