Thread: SLP header flex section ticking

As the title says, I have SLP headers and they have been making a ticking noise since I've installed them comming from the flex section.

I wrapped the Flex section and the ticking got quieter audibly, but scanning reveals up to 7 degrees false knock. Scanned before I installed the headers showed I actually had "less KR" with the stock exhaust on.

I know the ticking noise is common on the SLP headers, but I don't know if anyone has just tried replacing the interlock flex section to fix it. I"m thinking about going that route, but I'm not sure what size flex to buy. ZZP sells the 2.5" and the 3" diameter sections and I'm not sure which one is the right size. The SLP website says 3" collector, so I'm assuming that's the size of the flex also.


Just for reference I have the CAI and not the drop in K&N anymore, along with AL 104 spark plugs

I shouldn't be knocking with those mods, I run 93 octane.

I have been hearing horror stories about the zzp pcm's lately. Wonder if that has anything to do with it? How much KR were you getting before the headers?

I first installed the zzp pcm with stock set up (ubend/res delete with K&N drop in filter), no KR with that.

I installed the 3.4 pulley 104 AL plugs next with only my existing ubend delete. 4-5 degrees of knock retard, which is about average for those limiting mods.

I installed the headers and CAI and scanned again only with peaking at 7 degrees KR.

There is an audible ticking noise comming from the flex. I bought the headers used from a guy who later told me they ticked on his car too. would have been nice if he told me that before the sale. It's a common SLP Header problem.

The downpipe is part of the rear header, and no it's not hitting anything else on the car. My GM perf. front sway bar is installed upside down so there is no clearance problems.

Frankly I would just wrap the flex. The older versions of the SLP headers were coated in ceramic all the way down the rear header to the collector and past the flex. The coating caused them to tick. The newer version of the SLP headers are not coated past the end of the collector. That supposidly stops the ticking noise.

Also the way the collector sits at the back of the rear header and collector, you would be hard pressed to find anyone willing to accurately reweld a new section to that part of the rear header. I would strongly suggest not going that route. If you do that there, you are gonna be creating a weak link that will only lead to more problems down the road.

Wrapping the flex with header wrap should cure your problem and save you a bit of change in the process

I doubt ZZP's would help. I have one of their DPs with their interlocking flex and I get ticking during the higher idle of cold starts. It goes away as it warms, though.

I have a Hogan DP with the Interlocking flex and get NO tick at all. My first DP had the standard flex and it ticked.

You can buy just the flex joint from hoganperformance.

As stated above, my header wrap is installed around the flex section and most of the downpipe. that does eliminate most of the audible ticking, but it's still there bieng picked up by my rear knock sensor.

I personally believe that the guy I bought them from damaged the flex section as he installed and removed them. I did buy them used. The ticking noise corresponds to the vibrations of the engine as my engine speed increases.

I know I can find someone to weld it up, I was just trying to find someone who has actually done this and cured the ticking completely.

no tick from my s&s flex, but ive heard people saying they broke them and had to upgrade. im just crossing my fingers.

Your knock sensors are reading the tick as knock?

It must be, I've taken the supercharger belt off and I still have KR. Maybe the word "tick" isn't entirely accurate. The thing is, I can't seem to record it on a camera for reference. It's more of a rhythmic "squeak" that increases in frequency as the engine speed increases emitting from the flex section.

The sound is subtle with the header wrap installed so it isn't as annoying in the cabin. I'm only speculating my knock sensors are picking that up as knock. I don't know what else it would be picking up.

I have more header wrap, maybe I'll put on a second layer and give it a try before I go all out and replace the flex.

The flex on SLP's tick, plain and simple. Wrapping it only muffles it, you'll still hear it. After two years of that crap i had a flex from zzp welded in and no more tickl. Yeah!!

I don't know what flex they used i just told them it better not tick.

well, that's pretty much the testimonial I was looking for. Looks like I'll just have it replaced then.

I bought a weld in section of interlock flex from zzp. No tick, no KR. All is happy.

considering the cost of the flex is about the same as the header wrap, I wish I would have done this first.