i have an ap1 with a completely stock motor (33k miles). i am on the fence on upgrading just the retainers to ap2s or upgrading to ferrea beehive springs and retainers. personally i would like to keep things as simple as possible but i dont know if i will be ok with just ap2 retainers and stock springs at 600+ whp. seems like most guys upgrade the springs and retainers. if its safe to just get ap2 retainers i would like to go that route but i dont mind the other option either. what do you guys think?
i know its been discussed before but i just cant make up my mind. lol

 

I would pull the head have it ported and put new valves in and dual springs retainers oem head gasket arp head studs and check if oil jet bolts are updated. Or just use ap2 retainers and call it a day but if u end up dropping a valve you would have wished you replaced them.

 

ap2 intake retainers and keepers call it done dual springs cost me 5 hp. only did it for cam testing save the money for heat sheilding

 

How can dual valve springs lose hp??

 

Try pressing a harder spring with your hand.
It's the same for your camshafts...

Only plus side is that you can set your rev limiter a few rpm's higher

 

I was fully stock on 500whp and had the valve dropped 3 months ago Head gone,all cilinders scored

 

Was that on an ap1 head? I think you guys are right about the ap2 retainers.

 

Yeah Ap1 head,car covered 75k km

 

Ap2 valve keepers and retainers are stout enough to bend a valve in a mechanical over rev, before dropping one, unlike the ap1 valve train. Keep it OEM where you can, its more reliable. Even at 600hp. There is a point where driving habits and mistakes take a toll on the motor no matter how much money you spend on aftermarket parts. A bent valve is a lot better then a dropped one, so the ap2 OEM upgrade has proven to do its job. The only reason for aftermarket valve train is if you plan on exceeding a rev limit the stock valve springs cant handle. Like 10,000rpms+

 

OEM AP2 is the way to go, no need for aftermarket ones. Simple enough.