john hennessy wrote:
is the blanking plate leaking and allowing air into the exhaust of #4?
Removing the EGR valve exposed 3 ports; exhaust gas into the valve, exhaust gas out of the valve, and a coolant port. My thoughts were that since it was not leaking coolant it was sealing. I guess I should recheck that.
john hennessy wrote:
are we talking 100 deg. or more?
The difference was between 100 and 200 degrees. If it was idling it was only 100 degrees but if I revved it a few times the difference went up to 200. I was out driving once after that I and didn't think to point a temp gun at the headers a few minutes after I turned the engine off. Once the snow stops and it warms up some, I'll do this test.
john hennessy wrote:
are you running the variable intake system?
No variable intake - just bike ITBs.
rx7locost wrote:
What if you measured 12 inches from the flange. How do these temps compare there?
The difference is similar.
rx7locost wrote:
Have you checked he accuracy of the 4 vac gauges you used to balance your TB's?
That is a really good point. I'll double check my settings and try moving gauges to different cylinders to see if it matters. I'll try your ear test and see if I notice anything. Fortunately with the way the GSXR throttle bodies are mounted, the idle stop adjusts the #4 cylinder and #1-3 are all adjusted relative to the #4. Raising the rest and not losing my balance should be pretty straight forward.
If no one reports this being normal, the EGR blanking plate is sealing, and the ITBs are pulling equally, I guess the next logical thing would be to perform a leak down/compression test. I had the ports sealed but I'm hoping nothing fell into that cylinder and did some damage.