Mechanical over-rev advice needed
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From: Winnipeg, MB, Canada
Thanks! I'd kill for a sweeper that doesn't have either a big ridge in the pavement, a surface change, or some kink mid-way through it. We make the most of a marginal site. 65-mph slaloms are fun but it's stressful when the noobs spin out into the grass with course workers fearing for their lives. 
Granted, the noobs generally aren't making it to 65 mph...
Interestingly, it looks like I'm pulling more lateral and braking Gs with 255 Dunlops and mild STR setup than I was with A6s and the BS setup on this very unique surface. WTF? Can't complain, more Gs for less tire money!
No work on the car yet, other crap keeps getting in the way. Likely next week we'll get the valve cover off.
Granted, the noobs generally aren't making it to 65 mph...Interestingly, it looks like I'm pulling more lateral and braking Gs with 255 Dunlops and mild STR setup than I was with A6s and the BS setup on this very unique surface. WTF? Can't complain, more Gs for less tire money!
No work on the car yet, other crap keeps getting in the way. Likely next week we'll get the valve cover off.
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From: Twin Cities
Originally Posted by ALFYonso,Aug 3 2010, 09:28 PM
I did a bit of reading on this when I did a 3 ---> 2 money shift. It's quite possible you cracked some retainers. From what I understand, it's difficult to spot a cracked retainer from just taking the valve cover off as the crack could be extremely small. These small cracks might not do any thing immediately, but from what I've read, they'll propagate over time and eventually you'd drop a valve. This could happen 20k+ miles from now, but apparently some blown motors have been traced back to this. Replacing the retainers is probably the safest bet, but if you can find a way to inspect them, maybe start with that? 
There was a guy named something like "BillMan" that seemed to have a lot of experience with this, it might be worth your while to search out some of his posts on the topic.
Good luck either way... I got off okay w/my AP2 money shift (apparently they bend valves before cracking retainers), but I bent 4 valves doing the same thing on a GS-R I used to own.
There was a guy named something like "BillMan" that seemed to have a lot of experience with this, it might be worth your while to search out some of his posts on the topic.Good luck either way... I got off okay w/my AP2 money shift (apparently they bend valves before cracking retainers), but I bent 4 valves doing the same thing on a GS-R I used to own.
One sign down the road is "sinking" valves, where the crack allows the stem of the valve to creep downwards. I would assume this affects sealing too so a leakdown test should show it eventually.
One autocross friend here had an over rev or two in his past. He had no signs of problems, but we decided to do a group buy on AP2 retainers. The parts are still in a box for me, but he had his done and they found multiple cracked retainers. He said one dropped so far that it would have likely fallen into the engine at the next event. Yikes
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Not to sound like a noob, but you can just put AP2 retainers into an AP1? In what way are they better? I did probably 4 missed shifts on the road after I bought my 03, probably hit 10,000rpm for an instant, I was pretty quick about jamming that clutch pedal down, but 30,000 miles later it seems like I have no problems.
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From: Twin Cities
Originally Posted by NikosX,Aug 18 2010, 02:00 AM
Just wait for it. The kaboom will come. The damage has already been done.
There just seems to be a high correlation between dropped valves from cracked retainers, and people admitting to having over revved in the past. Is it 1 for 1? not necessarily. You may be fine.
And yes, you can put AP2 retainers on an AP1 engine. You just need a set of retainers and keepers (both of which have been redesigned for the AP2 engines).
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I just did an accidental over-rev on Saturday 
I didn't have my OBD2 logger taking data, but it was probably somewhere in the range of 9,750 to 10,250 RPM....went into first at 53 mph and left two black strips right off the track. It sounded OK when I got it back to my shop, but I'll be replacing retainers and keepers as soon as they come in. I'll post my findings. My engine has ~90k miles on it, 3 years of auto-x and about 10 lapping days.
I didn't have my OBD2 logger taking data, but it was probably somewhere in the range of 9,750 to 10,250 RPM....went into first at 53 mph and left two black strips right off the track. It sounded OK when I got it back to my shop, but I'll be replacing retainers and keepers as soon as they come in. I'll post my findings. My engine has ~90k miles on it, 3 years of auto-x and about 10 lapping days.
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From: Orlando
We'd pretty regularly do it in the T3 (ap2) car. 8500rpm in 3rd to 2nd gear. I think I did it at least twice and Peter did it a few more times then that. Engine never hickupped for many many weekends untill a red flag and faulty cooling fan finally did it in.
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I'd definitely say our tranny boxes are more prone to overrevs cause our gear selectors are so close...but regardless, I still look at it as driver error.
I've been driving manuals for over 30 years. I did it to my S2000 about a half dozen times after I first got the car, usually on a 5th to 4th, instead I'd go to 2nd.
I've been driving manuals for over 30 years. I did it to my S2000 about a half dozen times after I first got the car, usually on a 5th to 4th, instead I'd go to 2nd.