Most liked posts in thread: GNAT - Rebuild - The Sequel

What injectors do you have Nate? Might be worth it to upgrade while the labor is free...

 

I'm absolutely astounded the piston in #2 hole looks that good. Even though you have had bad juju with the head it could have been far far worse. Go buy a lottery ticket Nathan, you have a good luck streak going.

 

That cylinder was running lean for sure look at the other valve, same color, lean. Compare to all the others. Maybe the best indicator is the color inside the exhaust ports in the header.
Idealy, monitoring and tuning the each injector to get the same temp. in each cylinder will get the most performance.

 

The high end tuners dial in each cylinder, what's overkill?

 

Chad said he could do it........

 

YES, absolutely. You don't want to revisit this issue again. They will be able to tell you the results too.

 

Cooling System looked totally solid and had no problem.

 

High(er) res:

 

Send the injectors and the head to Jan. He has a guy that with cleaned and flow tested. I just had my old 450's done with new O rings and also got new pigtails.

Fyi~ mine are for sale for $ 290.00 of anyone needs them.

 

it looks like a typical burned valve to me.

 

Chad, I did not mean to imply a problem with the cooling system. I did not word that well. I agree with Colin, and think the likely cause was the O2 signal and probably partly the injectors. When you look at the pictures, especially the latest one you can see the detonation (small shiny pot marked area between the valve and the spark plug). I was trying to point out that these problems are often the result of several things and that their diagnosis is complicated. The detonation is the classic chicken or the egg. What came first the detonation or the burning valve. Potentially but not likely the problem was a blocked cooling passage in the area of the detonation. You couldn't figure that out without sawing the head open, and it isn't worth doing. The intent of bring this up is to point out that a lot of the time these things are caused by multiple problems, and you want to check what you can to eliminate as much as possible. Flow the injectors.

 

Jan makes extension cables with OEM plugs, wires, and insulation for the O2 sensors.

 

Thanks Nathan, hanging on every detail.

 

Really I nice trip from Ohio too! I think Nathan calculated the distance one time, it is do-able.

Snowmass, CO MITM ....

 

Anything to update ??

 

So when you are in this situation is it better to plan for what if and have a spare gasket made at the same time?

Never had this so I don't know what kind of turn around it takes to get one made ad hoc.

 

Is it being cut from copper sheet?

 

I think it would be a copper core with reflex style graphite style coating for a perfect seal.