Well, to start I'm dissasembling my engine and measuring everything.

The problem comes when I am measuring the diameter of the valve stem at three heights. The exhaust valves measure all of them 5'41~5'42. So it's over the limit. And the intake valves measure 4'955 all of them.

My question comes when I read the manual and in the manual both intake and exhaust measure 5'5mm.

And when I'm searching valve guides in ebay I read this about Supertech valve guides.

GDE-HD55-I: 5.5mm Intake valve guide,Manganese Bronze(x8)


GDE-HD55-E: 5.5mm Exhaust valve guide,Manganese Bronze(x8)


Where is the problem, I rechecked the measure and the intake ones measure less...


My engine is an European D16Y8 from a 97' Civic Coupe

 

does someone know anything about this??

 

When we rebuild heads we wouldn't measure the valve stem diameter. We measure the movement of the valve when it is installed in the guide.
This is what the manual says.


Measure the guide-to-stem clearance with a dial indicator while rocking the stem in the direction of normal thrust (wobble method).

Intake Valve Stem-to-Guide Clearance:
Standard (New): 0.04 - 0.10 mm (0.002 - 0.004 inch)
Service Limit: 0.16 mm (0.006 inch)

Exhaust Valve Stem-to-Guide Clearance:
Standard (New): 0.10 - 0.16 mm (0.004 - 0.006 inch)
Service Limit: 0.22 mm (0.009 inch)

When you install new guides you need to ream them to the proper size after installation.

 

I know and I've done that measure and in both valves, exhaust and intake are over the limit 0'28mm on intake and 0'36mm on exhaust.

Then because i need to replace the guides I measured the valves to be sure, and I need to change both guides and valves, but there appears the problem, intake valves 5mm and exhaust valves 5'5mm.

All I nned to know is if this is normal, because all aftermarket items are both 5'5mm.

 

Are you sure you have the right part number for guides? And are you going to use new valves with the new guides?

I had new Supertech guides installed in a GSR head and used Supertech valves, and had no issues. You sound like you know what you're doing, but when it comes to aftermarket stuff, some of this gets confusing. I'm not an expert on this, but perhaps aftermarket stuff isn't consistant or perhaps it's all oversized so you could install aftermarket valves in OEM guides by reaming them out? Either way, you could ask whatever shop you're having do this work, if you're considering that, and see what they say about reaming them from 5 to 5.5mm?

And also, some of the aftermarket guides are meant to be reamed out to fit. They DO squish inwards when driven into the head, which is why they need reemed out. My supertech valves fit perfect before guides were installed, then after, they would stick so they had to be reemed.