Hi everyone, so this summer I put SLP pipes on my XLT and put an egt in as well. I have the 597 engine with the pto oil line with 34mm carbs. I put 290 mains in from the stock 260s. Stock airbox. I decided to do a “plug chop” yesterday. Didn’t go for much more than a mile since it was acting weird. The issue I’m having is that when I go past around 3/4 throttle it has like a bog type thing. I can’t go past around 70 on the speedo. Forgot to check rpm sorry. The egt read a normal 1100 degree temp for center and mag pipe but pto only reads like 500-600. 3/4 throttle has higher rpm and goes faster and sounds normal compared to full throttle. I also think I have a bad head gasket as when I stopped the coolant comes out the bottle and I can see little black flecks when I look in the bottle. So is that pto cylinder pressurizing the system? And making it run like crap after 3/4? It totally seems like a main jet problem but the plugs say different and so does the egt. Maybe the entire jet rattled out making it extremely rich? Had that happen before. Here’s a pic of the plugs. The dark one is pto. Thanks for any help guys.
XLT WOT Issue
