like the header says, the ones with a f22c did u upgrade ur retainers when u did ur build ? if u did, which ones u chose ? thanks for the imput, trying to put everything in account with my build dont want anything blowing up.

is it needed ? since f22 only reving 8k, unlike the f20 9k

 

ferrera

 

Stock will be fine with stock redline and stock cams

 

Not needed but if your building the motor you might aswell upgrade them. OEM AP2 retainers are good for over 9k rpm btw.

 

If you planning to put 500whp and 20 psi + of boost you are better to put spring and retainer kit in ferrera brand.

 

Stock here.

 

I had bad luck or the shop f me but a valve dropped, I'm thinking because of a retainer cracking on my 07 with 40k. F'ed my life good. I would just go ahead and get piece of mind and do it. I wish I had.

 

I Paid for ferrera ,after nesar unfortunate situation.

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