read the article yesterday in car magazine about ap1 that misshifted .my understanding of the article was befor they found the bent valves they thought they could put in better springs and retainers which would allow the car to rev higher and therefor give them a safety margine in case of another misshift. does it make sense to put in stronger ssprings and retainers befor a misshift as insurance. thanks in advance for your consideration.

 

IMO,
Just drive properly and you will be fine.


Tim

 

I don't really think stronger springs will help in the case of most misshifts, Most misshifts occur on the 3-4 shift (where the driver hits 2nd instead of 4th). And generally, they're at the top of 3rd gear (~90mph) when they misshift. At 90mph, 2nd gear would probably be turning somewhere around 13K RPMs (I'm just guessing at that number). At 13K RPMs, I still don't think most available upgraded springs are going to be able to prevent damage.

With that said... a little extra headroom never hurts.

 

the article mentioned being safe until 11k rpms.

 

I did that same exact shift 3rd to 2nd, I was redlined in 3rd and slammed into 2nd on accident. I had the car for a week and did not take the time to learn the gearbox, anyways i didnt float the valves and the car was running fine after that, but i got worried and replaced the cotters (keepers) and retainers, however i still didnt see any sign off damage with those retainers I took out, so I feel like I wasted some money but I was just so paranoid about dropping a valve at least now I have that warm fuzzy feeling back.

 

I read the same article in SCC. What they don't say is that if you go with titanium retainers, you need to check and probably replace them every 15-20k miles. I ended up replacing the retainers in my 01 with 04/05 retainers because they are beefier and I would rather replace them then my whole engine. If I hadn't replaced them I would have worried all the time, so it was more piece of mind for me.

 

I didn't like that I was hearing that the titanium retainers had a service life of 15k miles. I also opted to replace my stock retainers and valve cotters with ap2 pieces back in January.

 

According to one of the most popular titanium retainer vendors, they recommended checking the retainers after 25K miles.

In any event, going to the Ti retainers doesn't make much sense for a street-driven car. For a track-only car, the answer might be different. 25K track miles is probably more than the expected lifespan of an engine, for one thing. For another, the chance of misshifting is a lot higher on the track.