Well the Civic was WAAAY over-due for a good valve adjustment (Honda reccomends every 30k miles, it'd been 70k since my last one!!) Anyways, the valves weren't too incrediblly loose, but they were definatley loose enough and way out of spec. So I went ahead and tightend them up to 1-thousandth tighter than spec ( factory calls for .007-.009, I went .006). Car started and right away the difference was noted, the motor was amazingly quiet!

Because of the weather however, I hadn't really been able to lay into the boost as of late, but this morning, between running late and taking advantage of the rare blue skies and dry road conditions, so I went ahead and laid into her a bit and whoaaaa.. damn near instant boost response and my AVC-R actually couldn't keep up, even on low boost which is set for only .45bar (shot up to .65 before the AVC-R caught it). Now the question, is this all in my head, or can a simple valve adjusment really influence the demeanor of the car/turbo so vastly?? Either way, I'm loving it

 

You adjust it yourself? Which tool did you use? Easy?

 

A 10mm wrench and flat head screwdriver, took about 20 mins or so to do all 16 valves, pretty easy stuff

 

i would say tha's the EASIEST job that i have done to my car so far
i just did it like 2 days ago..
does make it more quiet

 

Did you get your other problems fixed yet? The sputtering and starting problem.

I did a vavle adjustment recently and didn't notice any difference in boost, but it sure was quieter.

 

Ok, I sat down and thought about what would be the best valve lash for my turbo.

Generally thinking of how the valves perform when they are set:

Going with the tightest clearance--valves will open and close earlier, but the valve will open more. Good for moving the air in and out of the combustion chamber faster, not so good for motors that may suffer from overlap.
Going with the loosest clearance--valves will open and close later, but the valve will not open as far. Bad for moving air in and out of the combustion chamber in a hurry. Good for keep pressure in the combustion chamber.

I didnt know where to set mine at, so i went with the tightest spec, but no further. Remember setting tighter than spec will also accelerate wear and tear on the valvetrain and produce more heat as well.

Any else care to tackle this seemingly unknown area of performance for FI cars. Maybe someone that has unlimited dyno time to see what the best combination is?


[Modified by 93LSivic, 2:06 PM 7/2/2002]

 

Yeah, I would like a little more info on that too! Anyone?