So I just replaced my spark plug wires due to the number 5 cylinder boot contacting the header. Switched back to the standard 135 degree spark plug boots and number 5 clears just fine. Of course, now my number 2 boot is making contact.

It's only making contact on the flared end, right where the boot ends and the wire begins. What is the recommended fix? Just cut away some of the boot?

 

Insulate it with some Firesleeve?

 

MSD wires with bendable boots will clear your primaries.

 

Agreed. The MSD’s are “bent” a tad at the plug boot side, so you can index them. That’s what I run with my 2” headers and mine aren’t even close anywhere.

 

Actually the whole reason I'm doing this is I had a set of MSDs before. Went away from them because half the time I couldn't be sure if I got the damn terminal on the spark plug, one of them straight up refused to "click" onto the terminal.

 

When I put headers on many ls engine's f-bodys and trucks. I always click the option on tsp order for there fire boots. Then order a set of Taylor thundervolt 40/50 wires. Hasn't failed me yet. And yes some of them have had direct contact with a primary pipe for quite some time and have been fine.

 

I run the bendable msd wires..no issues. I have a hard time getting the lovely snap on #8. I have headers and it’s still a PITA. Idk how big your toolbox is, but they sell pliers made for spark plug wires. Ive had to use them a time or two to get a manhandle on #8 and got it to snap. Also, a bit heavy handed on the grease can make them not audibly snap..Sometimes I give them a tug and if they don’t slide back off I know they’re on. Sometimes you gotta sweet talk it until you feel the spark plug tip sit onto the snappy head inside of the boot, after I figured that out I can usually get all of mine to snap besides the aforementioned #8 lol. Don’t be afraid to give that metal retainer a slight squeeze or pry open with some needle nose if it’s not snapping, or not snapping positively enough. I’ve had to do this on a few peoples cars. But I’ve never had any complaints with my MSD wires.

 

I just ordered a set of fire boots like Kjduvall suggested.

 

Hopefully they work well for you. I know if my msds wouldnt snap on I’d quickly run out of cuss words and do the same. Lol

 

Dent your headers when all else fails

 

I run the bendable boot MSD's also.

Number 8 on the GMT-800 Silverado and Sierra's aren't as tough to get to as the f-body's but still a pain to get a good grip for the audible & and tactile *click. I always pull the oil dipstick tube out on the trucks to make it easier dealing with #8. I did have one MSD wire crimp failure and the connector stayed on the plug. Bought a identical set so I have 7 spares. I found you can get a little extra header clearance twisting the coil side boot to steer the wire away from the primaries as the MSD 32829 wires are a little long.

Started to re-crimp then said eff it lol

Attachment 712809

MSD 32829 wires are a little long but easily managed by twisting the coil boots to steer away from the headers.

Attachment 712810

 

I had a set of MSD's on my car for 100k or so, and then when I changed the plugs, I decided to change them out for a fresh set as well. Mistake. Although the first set had always performed perfectly, I had issues like yours with my second set of off the shelf MSD's.

I sent them back and went with a MSD set from Ton's Performance (Google or find him on ebay). Cost a little more, but fit and performed perfectly once again.

 

No idea if it matters here, but my MSD wires are from Katech, to use with their coil relocation kits…perhaps a better quality set? Jus thinking out loud.

 

I also use MSD bendable boots, and Hinson wire sleeves. Packages better than off-the-shelf boots.

 

My issue with the MSDs may have come from the fact that I had relocated my coils to underneath the cowling. Now I've got a set of Edelbrock wires and I think the only reason they were hitting was because the end of the boot where the wire starts has a big flared end. If it was as narrow as the MSD boots were it probably wouldn't have been an issue.

 

Didn't have issues installing my plug wires with the usual LS spec angled boot. For heat insulation I tried the cheap metal looking sleeve and could watch arc to primaries. Switched to the fiberglass type sleeve and no issues since. Even got them situated so the sleeve doesn't touch anything else.

Getting wires to fit under turbo headers was an adventure.