Hey guys,
As some of you may know, I have been trying to track down this issue with my small block chevy for quite some time. The issue is that cylinders 1 and 7 are about 300 degrees cooler than everything else.
I think I have pretty much checked everything at this point. Heres a list of things that i have replaced or checked:
Compression test - within spec
Leak down test - within spec
Plug wires - repalced
spark plugs - replaced
distributor - replaced (including VR sensor and igntiion modual)
coil - replaced
injectors - tested and swapped
lifters - swapped
valley leaks - checked
vac leaks - checked
From my timing light, it looks like im getting a good signal on the wires to those cold cylinders.
I think this pretty much covers everything.
But one thing I haven't done is swap in a different heat range spark plugs. I am running older AFR 190cc heads and AFR recommend to run Champion RCY9C as a starting point. I recently learned that these plugs are considered fairly cold plugs.
I've been trying to track down this issue for so long now that I'm staring to explore some radical ideas. I'm wondering if its possible for the plugs to cause this large discrepancy in cylinder temps. From listening to the exhaust, its obvious its misfiring. I'm wondering if there is some sort of strange dynamic to the airflow entering these outside cylinders and that these plugs are not enough to get things going? Is this even possible?
Any input or suggestions would, as always, be much appreciated.
As some of you may know, I have been trying to track down this issue with my small block chevy for quite some time. The issue is that cylinders 1 and 7 are about 300 degrees cooler than everything else.
I think I have pretty much checked everything at this point. Heres a list of things that i have replaced or checked:
Compression test - within spec
Leak down test - within spec
Plug wires - repalced
spark plugs - replaced
distributor - replaced (including VR sensor and igntiion modual)
coil - replaced
injectors - tested and swapped
lifters - swapped
valley leaks - checked
vac leaks - checked
From my timing light, it looks like im getting a good signal on the wires to those cold cylinders.
I think this pretty much covers everything.
But one thing I haven't done is swap in a different heat range spark plugs. I am running older AFR 190cc heads and AFR recommend to run Champion RCY9C as a starting point. I recently learned that these plugs are considered fairly cold plugs.
I've been trying to track down this issue for so long now that I'm staring to explore some radical ideas. I'm wondering if its possible for the plugs to cause this large discrepancy in cylinder temps. From listening to the exhaust, its obvious its misfiring. I'm wondering if there is some sort of strange dynamic to the airflow entering these outside cylinders and that these plugs are not enough to get things going? Is this even possible?
Any input or suggestions would, as always, be much appreciated.