DennisC6

I have a 1988 mustang gt i just put back together from putting gt40p heads and i started her up and she was running real rough and after a few minutes of it running like that the passenger side header was glowing red and there was a light smoke coming out of the intake. if any one knows how to fix this problem could you help me out? thanks very much!

86 newbie

if u still have ur cats on they could be clogged up

DennisC6

its only running lean on the passenger side. and i dont have cats..

AdderMk2

valve adjustment, and timing.

running lean at idle doesnt make headers glow

jojobanks

I would agree to torquing the valves and checking the timing. did you have a machine shop check the heads before you installed them? Did you use proper length push rods? are you sure that all of your valves are seating properly?

Dunno about the steam coming out of the intake. I would re-check that as well and make sure it's sealed properly and you don't have any vac leaks.

glowing headers at idle is easily a sign that those cyls could be running lean. I would fix the issue as fast as possible as well or it could end up warping your headers among other things.

The main things I would check is your timing, look for vac leaks, and make sure that your engine is getting proper fuel. It also wouldn't be a bad idea to do a cylinder leak-down test on the affected cylinders.