[boostdelinquent]

So I was doing some reserch trying to find info on how to determine piston to valve clearance and thought this might be helpful to other members who are running more agressive cams, oversized valves, etc. It directed towards domestics however I think it gives a pretty good idea of the various methods to check pistons to valve clearance. N/E how, here it is.

http://www.fordmuscle.com/fundamentals/pistontovalve/index.shtml

 

[CiViC_SI]

And for some that dont want to look at a ford site here is one that works for vtec engines

http://www.c-speedracing.com/howto/claymotor/clay.php

 

[88cr-rex]

I do clay for radial and checker spring for depth.

Rather know than put it together and wonder.

 

[DocHudson]

im in the process of adjusting the valve reliefs on my PM6 pistons now using a small 12 volt grinder. I've finished 2 so far.
the thing is i just copied the relief locations from some vtec P2M pistons (same as what i have in the engine) using circular (75mm) cuts from plastic book cover as a template and tracing the pockets on the plastic cuts.

it says in that ford site that you could weaken the pistons and upset the balance by removing material. i wish i could post pics of what i did to show you guys so you could comment if i have done this wrong ...

but if you could imagine replicating the relief locations from a PM6 (which is located towards the center) - to the vtec P2M (a little farther out).. would you think that I have carved out too much?

I need to know from some1 who'se actually had experience in adjusting a PM6for a vtec head

 

[DocHudson]

..or if you can show me a pic of a modified PM6 piston that had success if one of you gurus might have...I'd be SO grateful!!

 

[88cr-rex]

It depends on how deep you go. I honestly have never looked at any honda piston outside of a block but even standard v8 pistons usually have at least .3" of deck.

 

[BigTuna]

clay before your grind, you might be suprised how much Piston to valve clearance you already have.

 

[DocHudson]

Yeah i should have done that like you said but I'm not sure I'd be able to clay accurately. Anyway i have two finished already so I might as well finish off the rest.

I've been trying to inquire from SOO MANY members already but have come up short on answers.
Some say "they think" it will hit, some say they think it wont. Some say it never did on them, some say theirs went tragic.
I got tired asking. So i decided to do it myself instead of having mixed thoughts while driving the car.

The last thing I'd want is to be paranoid (noobie as I am) while revving the engine using a stage 2 cam.

 

[DocHudson]

Hey Big Tuna, how's the crx doing now? What's the latest on your car?

 

[BigTuna]

Hey Big Tuna, how's the crx doing now? What's the latest on your car?

Soon and very soon I will post up new stuff

 

[boostdelinquent]

And for some that dont want to look at a ford site here is one that works for vtec engines

http://www.c-speedracing.com/howto/claymotor/clay.php

Yeah, PirateMcFred posted up that link for me on my Honda-Tech thread. He also posted alot of other good info. Here's a link for anyone interested:

http://www.honda-tech.com/zerothread?id=1881681