Anybody Use Performance Welding Headers?

[Alan Roehrich]

About 3-4 years ago, we did some dyno testing for NitroPlate. On a standard set of roadster style dyno headers, a 406 small block Chevy making about 500HP gained approximately 2% HP when we coated the headers. It took tuning to get there.

The first thing we found was that the coating leaned the engine out considerably, the average EGT increased by well over 120 degrees. We had tuned the engine to around 13.2:1 AFR, which yielded the most power before we coated the headers.

With no other changes but the coating, the AFR went to around 14:1, and the EGT went to 1480 + degrees at the end of a 20 second pull. That first pull was down about 4%-6%. However, after we got the AFR back to 13.2:1, and the EGT back down to 1360 or so, we had gained a little over 2% over the base line.

If you tune and record EGT, you may find that you cannot get the EGT back down to where it was before the headers were coated. The coating reflects heat back into the header, so even properly tuned, the EGT is often higher than it is with an uncoated header.

We did not do any testing to see if there were gains to be had because of a reduction in under hood heat. We hope to do more testing in the future, but we haven't scheduled anything as of yet. We did test intake coating, we found around 1% or so on a dual plane single 4 barrel intake coating the exterior only, top and bottom, on a 350 small block Chevy 350HP limited circle track engine.