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Here is the how I got the K20a2 cams to work on the K20a3 head. You need the K20a2 cams (or type-r, tsx, crower...), K20a2 rockers and pins, and k20a2 rocker shafts. The pins in this picture are how they come in the A2 head

You have to switch the pins in the left and middle rocker like this picture

This locks the left and middle rocker together so that the middle rocker will not bounce around due to the cylinder head not having the lost motion spring.





This makes the left valve always ride on the vtec lobe and the right valve rides on the non-vtec lobe. When vtec is engaged by the solenoid it locks all three rockers together the same way the factory does and you have a regular working vtec.

Edit by Signalpuke:
More info on Rockers here which rocker to choose??
Pics are still not working in the first post. Can anyone provide some visuals?
 

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Here is the how I got the K20a2 cams to work on the K20a3 head. You need the K20a2 cams (or type-r, tsx, crower...), K20a2 rockers and pins, and k20a2 rocker shafts. The pins in this picture are how they come in the A2 head

You have to switch the pins in the left and middle rocker like this picture

This locks the left and middle rocker together so that the middle rocker will not bounce around due to the cylinder head not having the lost motion spring.





This makes the left valve always ride on the vtec lobe and the right valve rides on the non-vtec lobe. When vtec is engaged by the solenoid it locks all three rockers together the same way the factory does and you have a regular working vtec.

Edit by Signalpuke:
More info on Rockers here which rocker to choose??
Hey bro do you have pictures of how to lock the pins for the lmas not being there in the exhaust side no pictures are showing up thanks
 

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Hey bro do you have pictures of how to lock the pins for the lmas not being there in the exhaust side no pictures are showing up thanks
I asked at InlinePRO for Jeremy Allen, who started this thread. Maybe I will get a reply, definitly I will see what I can do for you. I have already an idea how it works, as the description of @Jeremyinlinepro is very picturable. The only issue of his approach is only one valve is at low speed cam in low speed lobe mode, the other valve is always in VTEC mode. His approach locks the left rocker to the high speed rocker arm, which means exactly this. Only in VTEC mode both valves are in high speed lobe mode. A simple approach, which may led suffer idle a bit. May, because the swirl which is induced by that is significant. This may helps to compensate the longer opened valve disadvantage.

I think lmas are 'lost motion assemblys' they're the springs under the vtec rocker that controls their motion against the vtec lobe.
Thanks Bjorn for your look behind that acronym and the explanation.
 

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Here is the how I got the K20a2 cams to work on the K20a3 head. You need the K20a2 cams (or type-r, tsx, crower...), K20a2 rockers and pins, and k20a2 rocker shafts. The pins in this picture are how they come in the A2 head

You have to switch the pins in the left and middle rocker like this picture

This locks the left and middle rocker together so that the middle rocker will not bounce around due to the cylinder head not having the lost motion spring.





This makes the left valve always ride on the vtec lobe and the right valve rides on the non-vtec lobe. When vtec is engaged by the solenoid it locks all three rockers together the same way the factory does and you have a regular working vtec.

Edit by Signalpuke:
More info on Rockers here which rocker to choose??
Will a z3 rocker assembly work? With a2 cams in a k20a3?
 

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Here is the how I got the K20a2 cams to work on the K20a3 head. You need the K20a2 cams (or type-r, tsx, crower...), K20a2 rockers and pins, and k20a2 rocker shafts. The pins in this picture are how they come in the A2 head

You have to switch the pins in the left and middle rocker like this picture

This locks the left and middle rocker together so that the middle rocker will not bounce around due to the cylinder head not having the lost motion spring.





This makes the left valve always ride on the vtec lobe and the right valve rides on the non-vtec lobe. When vtec is engaged by the solenoid it locks all three rockers together the same way the factory does and you have a regular working vtec.

Edit by Signalpuke:
More info on Rockers here which rocker to choose??
Could you use z1 cams as well same setup as the a2 if I’m not mistaken
 
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