He's obviously a ganster, or simply insane.

I understand the point of it, but I'm just questioning the doubling of the spring rate. It seems excessive, and may add accelerated wear to valvetrain components, and cost HP. For a low power NA build, I would thinking using Ferrea's 60lb or 70lb springs would be more a more than sufficient upgrade. Not to mention, the heavier spring you go with, typically the shorter life cycle. I don't want to be taking these heads off for anything to be honest.

Rocker retainers, and some lightly upgraded valve springs and call it a day.

Now sure, for big FI power, I can see this but I can tell you from just a few conversations with some of these companies, they just want to slap in their product of "choice" regardless of the build. Like rods for example, a 200whp, NA motor doesn't need super-heavy duty rods that are heavier than stock ones, especially when you can buy lighter forged ones that are WAY stronger, but yet that's what they "recommend".

Point is, I honestly just don't have much faith in a lot these companies for motor builds.

If you're doing a low power build, why don't you just get a factory block at this point? That would eliminate all the guess work and reliability issues

It's honestly what I'm leaning toward, except using the '17 block/case and valvetrain components (and intake manifold) for all the good internal upgrades, and then using all my '15 sensors and wiring harness. Then adding rocker lockers, some upgraded valve springs, rods, bearings, but stock pistons and CR. Really, just a reliability build, I don't really need anymore power at this point.

For something like that, prob alot easier and cheaper to just find a nice low mileage full '17 motor and have someone do the work.

It's what I've been racing the past 1.5 years without any issues. Bought my car with about 33K street miles on it, then straight to racing with it. It's unopened inside, but it is a '15, which I know already has the second version of OE valvetrain upgrades. It literally only sees high RPM, and knock on wood has been great so far. Uses 10W50 oil, oil pan baffle, and so far so good.

It's these rockers that have me F-ing paranoid!

The real question is, are the OE pivots the same exact dimensions for 13-17+ cars....there are 3 different versions of internal valvetrain components.

I want to confirm these 100% work for all years by confirming the engine pivots never changed. The kit from the OP seems to only have 1 version which supposedly covers all years.

Honestly if I were going to open up the heads, I would get the retainer kit so I will never have to worry about staying in the high RPM. Otherwise, just get a 2017 long block spare in case you blow yours. (But this is more of a band-aid than solving the issue)

10W50 is a REALLY thick oil. Did you do any UoA on it after oil changes?

Actually, he has both versions(I called him up and you can specify which one you want)

Def adding rocker stoppers to my next motor....

It's not really heavy oil at all for racing. Toyota Motorsports Germany, who builds, supports and races factory 86 cars in Europe uses 10W60 and now 5W50 in their motors w/ oil coolers. They won't go anything below 5W50, for proper oil pressure and oil films at high temps/RPM. I've spoken directly with their engineers who see everything from sprint and endurance racing motors, they vigorously recommend it. That's how they avoid spinning rod bearings at similar NA power levels...;)

This whole "tight clearance" it needs thin oil thing with this motor is a complete myth....10W40 or 5-10W50 racing oil in these cars at 200-230 deg. is right at home. Did a UoA early on and it was fine when I used 5W40, and TMG told me to bump up to any high quality XW50...been using it every since, rods seem to be happy.

Bingo. Oil is rated at 212F. Know your temps and monitor pressure, and use the oil accordingly. At redline, my pressures are routinely 88-90+psi at 215-230 temps, I virtually never see anything over 230F. Care idles warm at about 18-19psi.

that's my point. Are the pivots in this kit (http://denstoj.com.au/retainer-kit/) the same as in the '17+ cars, or the 13-14 cars?

If these OE pivots changed spec between 13-14, 15, and 17+ cars, then which pivots is Denstoj selling?

They are not selling the pivots, you have to send them in to be modified. As far as I am aware the only change in pivots is the size of the oiling hole. The old part number supersedes to the newest last I checked. The early engines had different sized oil holes in each head. The newer ones have the same in both sides.

hmm, doesn't read that way to me. It would be terribly inconvenient to have to ship off your pivots to Australia and then wait to receive them back, before you can start building your motor back. That said, it would be the sure-fire way to ensure you get your same exact parts back.

I read it as their "kit" provides you with everything, and once you pull out your old pivots, to send them back to them as core returns. That's usually how a core refund works.

Regardless, I'm shocked nobody here in the USA has come up with a solution like this. I like this alot better than the AWD tuning rocker stopper solution.

I could be wrong. Won’t be the first time.

The way it's explained on their website is that they ship everything to you and they refund you a core charge upon receipt of your parts, unless it's changed since I saw it