Car Analogy

As I've said before, always be careful that your efforts to prevent something don't inadvertently cause it. There is risk involved in any surgery. On your body, or your motor.

No, the valves don't go boom immediately upon a single mechanical overev. They crack, and over time they fail, and valve drops. Often failure occurs during comparatively mundane driving.

Sure, its possible to overrev to the point of immediate failure, but thats more likely to be from valve float that allows piston contact, not from retainer going from fine to failed in one shot.

lane_viper

Comparing replacing valve retainers to surgery is a little bit of an overstep.

I agree that this procedure is not as easy as changing the oil. But having done it myself on my S2k, and having replaced valve springs on other cars, I would say it's maybe a 3 or 4 out of 10 in difficulty.

You guys are right, that this really adds no value on resale, but it's really not an expense either. $50 maybe, if you do it yourself. Not to nitpick, but I take what a previous owner says with a grain of salt, and let the car speak for itself. The owner telling me it's "never been over-revved" to me, is chalked up to "It's never seen rain" or "I only drove it to church on Sundays".

$50 is not too much for piece of mind in my book.

OP can decide for himself, but to me this is getting way to over blown.

darcyw

Well...perhaps with respect to aeronautical engines...I wouldn't trust modern German automotive engines out of warranty.
Seriously, in regards to the early 2000 to mid 2002 F20C, again I'm more concerned with the oiling with forced induction or track use over retainers.

However, peace of mind is priceless.
good luck!
darcy

Mr.Matchbox

Sadly you are right that "Made in Germany" cars are not as good anymore as they used to be. Thats why i own this little japanese racecar with the little valve retainer issue.
And yes, you are absolutely right that peace of mind is priceless.
Thanks! I will take my time doing the retainer job, carefull.

Car Analogy

Keep in mind the op is not mechanically adept. It may not be difficult, but for someone whose experience is limited, this would not be the place to learn. Getting it wrong would be bad.

I also don't trust mechanics with this car, unless they have S specific experience. Bring them a Porsche, and they know they need to get it right and will lookup how its done and follow procedure. Bring them an S, and all they see is the H badge.

If they cut you open, its surgery. Thats why they say any surgery has risks. They mean even the simplest of procedures have risk.

s2000Junky

Correct. The only way you can tell from the top is if the crack is severe enough for the valve stem to actually start to sink in, which in that case its a immediate change out. Otherwise lets be strait, ap1 valve retainers dont just crack just because, or because they are weak, but because someone has money shifted the car once or multiple times. If you don't do this, don't expect them to crack, but for added insurance if you do money shift, the ap2 retainers are stronger and could prevent a dropped valve down the road from an abused motor.

DanielB

I track my MY00 AP1 regulary (40 days in three years) and chose to do the oil squirter banjo bolts mod and also added an oil cooler for insurance. I adjust the valves each season and check for sunken retainers. I have no plans to do the valve retainers unless I make a mistake and miss a shift at the track. There are no benefits unless I make that mistake, there's no guarantee the retainers would crack if I did, and the failure is not going to happen immediately. I'm quite mechanically adept, but have learned that messing with anything always has risks and for this issue, I don't see enough upside for me to warrant it unless I over rev.

All that said, this is what works for me. If others feel better making the change, I would hope they do so with the realization that there's always a chance of unintended consequences occuring.

One question for those who have experienced mechanical over revs: at what RPM range does bouncing a valve off a piston become likely with the AP1 stock valve train?

s2000Junky

Hard to say exactly, but I recall seeing a post in the FI forum years ago from Realstreet saying he revved up to 10,500rpm before getting severe valve float, so given that id say there is a good chance around 11k. rpm. That's not too hard to do going from say 9k in 3rd gear to 2nd by mistake. Classic move. Depends on how fast you catch it. Ive done it a couple times over the my 15 years, and have been lucky.

DanielB

So if we take 11k as the point at which valve damage becomes possible, the additional safety margin the upgraded retainers provides is around 2k RPM. If I've done the math right, 9k rpm in third gear on an AP1 corresponds to 12.4k rpm in second. The actual rpm with the clutch out would probably be less as some vehicle speed would be lost spinning the engine up. So even with the upgraded retainers, shifting into second instead of fourth could still result in damaged valves - assuming you let the clutch out completely before realizing the mistake. Does that sound right?

If I have this right, then the scenario where there's benefit to proactively upgrading the retainers is when a 3-4 upshift at redline becomes a 3-2 downshift and you realize the mistake before fully releasing the clutch, but not fast enough to avoid exceeding the 9k redline. I don't think there's any way to estimate the probability of this occurring. It's up to each person to decide if the way they drive makes this scenario plausible, or even likely. My point here is to illustrate that there is a benefit to proactively doing the swap, but the benefits are more limited than I think most realize.

s2000Junky

Fair assessment.

I will add my own, which is the ap2 retainers in this scenario would seem more likely to hold on to the valve stem and bend a valve vs crack the retainer and drop a valve. Both suck, but one scenario the bottom end can survive. Id much rather pull the head and replace a bent valve then lose the entire engine.