Hey guys, whats up? Okay, i searched for this on HT, accordtuner, honda society, preludezone, Prelude Power, hondaswap and Google and other miscellaneous forums, there was some information out there but nothing specific to the question I had so I thought you guys are a good source of information so it would be more direct to ask.

Well, I am wanting to buy a set of Skunk2 high compression valves for my H22 in my 94 accord coupe, however, they come in 3 sizes. I understand they come in stock, .5mm and 1.0mm. I am uncertain as to what the 3 sizes represent, if you get my point? Stock size I understand would just change out the stock valves for the same sized aftermarket forged metal high compression valves, but, with the oversized valves, what purpose do they serve? Do I have to mate them with other products in order to get them to function to their optimal performance?

This is what I was unclear on. Currently I am running a JDM H22 motor with blox typeB cams, titanium retainers and dual valve springs, adjustable cam gears (and other parts) and just had all the seals etc... changed along with my head gasket. I am in the process of scheduling tuning and a cam Degreeing but wanted to get these valves in the motor before tuning due to the higher compression of the cams themselves.

These are what I was looking at purchasing --- http://cgi.ebay.com/ebaymotors/ws/eB...d=380210907433

I just wanted to make sure whether the oversized valves might be a better option for me to pursue or to stick with the stock sized valves.

Sorry for the long and drawn out question. Thanks in advance for your information/help.

 

The over size is in correlation to the outside diameter of the valve head itself. They allow for more air flow into the combustion chamber. Over sized valves are similar to using an OS piston. If you have a 30mm stock valve, a 0.5mm over sized valve would be 30.5mm in diameter and a 1mm OS would be a 31mm valve diameter. They would require that the valve seats be cut/angled to accept the larger diameter valves. Just as an OS piston requires the cylinder bore to be larger.

Sometimes running 1mm over will also require the valve relief in the top of the piston to be made larger/altered. It is also recommended that the valve to valve clearance be checked & documented. Some cams don't always work with OS valves, or they will work but they will have limited timing adjustments available.

 

So I gather from this I'd be better off just using the oem size high compression valves.

 

The size depends on how much you want to spend and what your setup is going to be. I always run Ferrea +1mm oversized valves, but that's just for my particular setup and budget.

 

Thanks for your help guys, I ended up buying the Skunk2 Pro Series standard sized high compression valves for my H22.

http://www.skunk2.com/mm5/merchant.m...de=310-05-5360