DIY Valve retainer replacement with head in place
#21
When you loosen the valve adjuster screws before you remove cam cap bolts, do you loosen them all at TDC cylinder 1? Or do you crank the engine to get the cam lobe off the other rocker arms, and then loosen the other ones?
#22
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Originally Posted by jyeung528,Apr 13 2010, 07:09 PM
is it okay to replace the exhaust side with ap2 retainers using the stock springs?
Originally Posted by s2k_boy,Apr 14 2010, 03:13 PM
^ yes
#23
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Originally Posted by Billman250,May 3 2010, 06:06 AM
No, it is NOT ok.
#25
Moderator
Intake side gets AP2 retainers and keepers.
Exhaust side stays 100% stock.
NO AP2 springs on either side.
In theory, adding weight to the exhaust valves will lower the RPM needed to make piston-to-valve contact.
Over revs go like this on a stock AP1:
-Mild over rev: intake valves float, splitting the retainers (likely around 10k)
-more severe: at about 10,700 rpm, the exhaust valves contact the piston.
The purpose of the AP2 upgrade is to raise the retainer-split-rpm over the exhaust-valve-float rpm.
Bottom line, you do not want to lower that number (10,700)
So after the upgrade, your engine can withstand 10,600, instead of 10k.
Exhaust side stays 100% stock.
NO AP2 springs on either side.
In theory, adding weight to the exhaust valves will lower the RPM needed to make piston-to-valve contact.
Over revs go like this on a stock AP1:
-Mild over rev: intake valves float, splitting the retainers (likely around 10k)
-more severe: at about 10,700 rpm, the exhaust valves contact the piston.
The purpose of the AP2 upgrade is to raise the retainer-split-rpm over the exhaust-valve-float rpm.
Bottom line, you do not want to lower that number (10,700)
So after the upgrade, your engine can withstand 10,600, instead of 10k.
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TKY (04-29-2020)
#27
If you do not have air, after you remove the cam, can you rotate the crank to TDC fro each pistons so when the valve drops slightly it won't fall in? I don't have compressed air.. It was an idea, I could even put some string in there too so it does not hit the top of the piston.
#30
Yes - you need the AP2 cotters, if you use the AP2 retainers. The angles in the AP1 parts are different (you can search for a pic that shows the difference).
You *need* to use the corresponding cotters to match the retainers. I'm sure they will fail otherwise.
You *need* to use the corresponding cotters to match the retainers. I'm sure they will fail otherwise.