V6 Timing chain questions.

[vlad01]

Doing my usual rabbit hole thing, I found this.

Looks like it has some potential, but I am sus on the pin's swagging length and quality, looks shithouse compared to OEM and could potentially come apart with the harsh vibration the damper would experience.

But the machined larger polymer pad looks pretty well thought out to accommodate double row chains.

They are claiming far less wear that the OEM.

Anyone game to test one out on a hot motor? This is were the stock one usually fails, and although the chains do fair ok without dampening, I think they would def benefit from one and should reduce overall wear and "stretch". " "" " meaning it's not the metal stretching, rather the cumulative effect of small wear induced play in each part, the roller, the pins, and of course the roots of the teeth on the sprockets themselves wearing deeper and wider.

There is a customer's installed pics in the review section and indeed it covers the entire double chain well.


https://zzperformance.com/collections/3 ... cac0&_ss=c


I also have toyed with the idea of having a timing chain oil squirter, that should make the chain and sprockets last much longer as the one down side of roller chains is they need good quality lube and plenty of it, once they have that however, they are much better than other chain types for performance aplications. Only issue is I haven't seen any metered squirters that are in the compact form/profile of a chain squirter, only for the pistons ones which won't really fit in so well, but I suppose one could always meter one with the right sized feed hole, metering/check valve would be nice too like the piston ones have.

[immortality]

Yup, I think the biggest issue is a lack of oil to lubricate the timing chain properly and everything else is just a band aid to the problem.

I also have a idea to create a oil squirter for the timing chain however I've not tested the theory yet so won't say any more just yet however it's dead simple in concept.

[immortality]

Here it is, dead simple really and all you need is a small drill bit. I'm going to try 1mm. Pic should be fairly self explanatory. This is a ecotec timing cover, I think the earlier 3800 V6 ones are similar.

WhatsApp Image 2026-06-141 at 3.16.21 PM.jpg

I haven't yet tested this on my own motor so try at your own risk!

[immortality]

Whilst you have the timing cover off it may pay to do this mod too.

WhatsApp Image 2026-06-14 2at 3.16.21 PM.jpg

Now this isn't required for a daily driver but for a engine that gets abused and spends a lot of time at high revs it's probably a good idea.

When ever the oil bypass opens, the oil from the bypass goes directly back into the inlet side of the pump. At sustained high revs when the bypass is open there is a fair amount of oil that is just circulating around that circuit through the oil pump been heated. By dumping that oil back into the crank case you aren't circulating the same oil and creating excess heat that isn't required.

[vlad01]

The ideal location for chain lube is on the inside and more specifically, the lead in into the crank sprocket as this is where the most load and wear occurs as this is a boundary layer lubrication condition. Flooding that with oil will help it move into a mixed lube condition probably, (mixed as in boundary and hydrodynamic).

You def want to lube the inside as the centrifugal action will force the oil through the chain, but that same force will just fling the oil off the outside if that's the only place oil is being jetted onto, that will also fail to get into that mixed lube condition that a flood of oil being wedged into the lead in should create. This is why nearly all OEMs squirt the oil where I've drawn the arrow, or at least the same position relative to other engine chain layouts. A 2nd jet in the opposite diagonal corner could help also, but that main one is the most loaded up contact points.

The two red lines shows the gallery location for the front bearing. One could add the jet there, but it's a little far away from getting to the right spot, still better than nothing, but one can drill another smaller gallery to the arrow side so the squirter can be located more ideally. You'd also want to be careful not to get too close to the chain as they flop out of line far more than you think, evident on Gareth's oil pump cover.

The Holden 308 had the right idea as they literally ran this type of chain with no damper from factory and they seemed to do alright chain wise because they had the squirter there, they just had a sucky oil pump setup that was the letdown.

chain lube_ideal location.png

[immortality]

Oil is funny stuff and will get itself into places you'd never think, the oil is under a decent amount of pressure (unlike the 308), it'll end up where it's needed even if most simply flings off.

I did consider modifying the block but drilling/machining a block is work that most people simply can't do themselves and it requires a lot of cleaning afterwards, my idea can be done in a afternoon without the need to pull the engine out. But each to their own I guess.

[immortality]

Anyway, the plan is to use some clay under the timing cover to work exactly where the timing chain runs to figure out the best placement to drill a hole. All going well the jet of oil will squirt right through the chain hitting the roller elements. I actually expect the best place to drill will be about half way along the oil gallery in the timing cover. It all really depends on where the top sprocket sits, in the picture I just made a guestimate.

I would have done this a lot sooner but when I put the VT engine back together I used sealant on the gasket which means it's going to be a bastard to get off again and I didn't have a spare gasket till recently.

[vlad01]

I think the only way you'd know for sure is to run up the pump on a stand setup with an external electric motor or something to see how much and what the jet is like if one can't have a complete running stand engine, or some development mule with windows cut into the timing cover. A high speed camera would probably be necessary to see in detail. Things are fast and very windy in an engine, so theory can and often does break down and needs to be rethought when carrying out real world tests.

[immortality]

The joys of backyard engineering. You modify and monitor. Long term timing chain wear is the ultimate indicator.

But you don't learn if you never try

[immortality]

I completely underestimated how close the timing chain comes to the inside off the cover.



The chain tensioner actually covers the ideal location.