Burned plug wires - ideas from the gurus?

[hobo]

Guys,
The old '69 Nova w/ a 468, blower, headers, & Merlin heads decided to run awful rough this spring. When checking the plugs I noticed that three of my plug wires had been seriously burned by the headers, and this was "through" the spark plug heatshield boots that I have on each plug. Tonight I changed plug wires and took it for a ride. When I got home after about 15 minutes of driving, three of the plug wires had smoke coming out of the heatshield boots. I run a coil-per-cylinder MSD ignition system, so the wires all come straight down to their respective plugs - it's not like they're wrapping around the headers all over the place. Also, timing maxes out around 34* total and all in by 2500 rpm, so I don't think I'm advanced to the stage of causing overheating. Finally, I'm running a Bill Mitchell Hardcore 870 carb with 80 jets in the front and 87s in the rear, so I should be rich enough to avoid any lean overheating issues.

What do the rest of you do to deal with heating issues like this?

As always, Thanks!

[pat mccarthy]

bbc with headers can burn the boots you want them away from the headers i have only seen one set s of wire boots that can take the heat if your runing the stock tin heat shields with the headers i would take them off they were never made to take the added heat from a thin wall header. they will just be super heat the shield and burn up the boots .i used the boots you can bend for bbc a set 90 boot can work .a photo would help . i think your ok on jets and timming it is just a bbc thing i use RM wire looms and takes time to do the wires so they are not in the way of the header tubes

[skids72]

It isn't real pretty but I use this stuff on two of the wire boots that pass too close to the headers. I can bend the other boots to give enough clearance but these two are just too close...

[hotroddaddy]

I used similar stuff on the merc. i think they were made for the ricers, but i used them anyway, worked real good!

[hobo]

Thanks everyone. I made a couple of 90-degree boots in place of the straight ones and that helped two of my three cylinders. #5 seems to want to touch regardless, and I can see where the previous owner "dimpled" the header to make room for a socket just to change the plug. I'll experiment with some heat wraps and "modify" the header as necessary I guess.

I love the BBC, but don't seem to recall some of these issues with my SBC...

[hobo]

What finally worked was a combination of the Accel "shorty" header plugs and the heat boots. Looks like I'm back in business, but I have a whole roll of header-wrap on hand just in case I need to make "adjustments."

Thanks again everyone...