Hey there, to those who have ap1's with the f20C, was it ever verified that you should only swap the intake side only with ap2 valve retainers/cotters? If so what was the reasoning behind this as to why the exhaust valve retainers were not swapped out in favor for the ap2s? I thought I remembered Billman saying that the theory behind this was to raise the valve float limit of the intake side (thus swapping in ap2 retainers but not to lower the exhaust valve to piston contact rpm (thus keeping stock ap1 retainers)? If the ap2 retainers are so superior why isnt the exhaust side swapped as well?
Also was it ever verified as to how to find out for sure if you have the new model style retainers according to VIN number? Thanks for any input, i8ve tried searching but its a never ending circle.

 

intake only is correct. you don't swap exhaust because (I believe) you'll bang up the valves before the AP1 retainers break. As far as a cut off on the old style retainers, I'd assume it's MY 2004 + that have the new ones

 

2000-2003 old retainers.

2004-2009 new retainers.

Change intake side only. Using AP2 retainers on the exhaust side will lower the float RPM it takes to bend them. It would defeat the purpose. The idea is to raise the over-rev RPM that can cause hidden damage.

 

I changed both sides since I was in there and bought the car used. I try not to go past 7K.

 

thanks for the response billman, but I still dont understand how swapping in a more superior retainer on the exhaust side will lower the valve float rpm? Wouldnt you want superior retainers on both the exhaust and intake side? Sorry if this sounds confusing, its just the way that I see it is that if you swap in stronger retainers you raise the rev limit at which damage will occur.

 

Because the new retainers are heavier. more weight equals more float. The exhausts are already the first to contact the pistons. adding weight will lower the RPM it takes to do so.

 

FYI:
On post MY'04 F20C2's sold in Europe Honda installed "AP2" retainers on intake and exhaust.

 

To clarify what Billman is referring to - the issue has nothing to do with the normal RPM range for the S2000. The issue is RPM overhead in the case of an accidental mechanical over-rev.

I took my car to Billman to have my intake retainers replaced for piece of mind. This was done as a preventative measure to eliminate the specter of dropping a valve (or two) due to possibly cracked retainers. I was tired of inspecting my retainers following a rookie move on my part (that resulted in a mechanical over-rev in 2004). The estimated RPM based on the speed that the "money-shift" happened was approximately 10,200 RPM, which is right at the point where dishing/stretching/cracking starts to occur. My retainers ultimately showed stress marks, but no cracks. They were possibly spared by slight slippage of my former clutch combo: Toda FW, Mugen PP and OEM disc.

Nevertheless - the piece of mind having the intake retainers replaced with AP2 retainers has been priceless, and BIllman is second to none in the process.

AP2 intake retainers (in an AP1) will survive an over-rev that will otherwise bend your exhaust valves. AP1 exhaust valve retainers generally will survive a mechanical over-rev up to the point the valves bend (replacing them at that point then becomes a given). Therefore, there is no benefit in installing heavier exhaust retainers to prevent cracking... the valves will be toast before the exhaust retainers will crack in the first place, and installing heavier retainers will just lower the point at which this happens. The OEM AP1 exhaust retainers work perfectly well - it's the intake ones that need beefing up.

AP2 intake retainers and AP1 exhaust retainers - in an AP1 - give an otherwise OEM motor the best buffer against mild over-rev buffoonery (of which I'm guilty of).


Just for note - I don't think there's any benefit in replacing the exhaust retainers in an AP2 with AP1 retainers. The engine doesn't rev high enough to likely warrant such a mod.

 

Well its not the first time Honda dropped the ball, maybe they should spend more time on the forums and learn more about the car in real world over-rev situations.

While they are at it, they should have re-designed their pathetic timing chain tensioner before I did.

 

(I can't give credit to the person on s2ki that found this info because I don't remember who it was)
Maybe..... the reason Honda changed retainer design in F22's has nothing to do with overrev protection or F20 retainers being weak or what not.
Maybe.. its just coincidence the F22's were released at the time the new retainer/cotters were released.
Maybe.. that is why they were installed in post MY'04 F20's

Why would Honda not recall F20's to have the retainers changed as they did with the oil jet bolts, if they figured it was a weak design.
(Agreed, changing retainers is a lot more work but in 2004 there was no financial crisis)

Spending an hour at 8000 rpm at the Autobahn is within spec, touching 10500 rpm after a money shift is not.
If "operator error is not our problem" was part of the decision not to recall they are probably right as it opens a can of worms:
Recall AP1 rear suspension for snap oversteer issues> install AP2 rear subframe, knuckle & lower arms.
Recall AP1's to have VSA installed to assist driver in unwanted situations.
Recall AP1's on 16" wheels to swap to 17" wheels to get rid of dangerous S-02's in the rain.
Recall MY-00-03(?) AP1 softtops to change softtop to glass rear window for obvious saftety reasons.

- offtopic a bit -
Re-design?
Drilling a bigger hole = re-design?

Unless you tell us (S2ki community) what is is you do to the TCT's I can't agree with re-design

IF oil flow into the TCT is the problem I think the oil channel in the head feeding the TCT is part of it as well.
Oil has to flow around the TCT in a pretty small cavity where turbulence might come into play too as the oil has to flow "in a circle" to suddenly take a sharp right into a small narrowing hole entering the TCT.
This is what I did:

So far no TCT noise.
I did have some (I think).