Jet Hot Coat Headers

Guys,

I just had aftermarket headers with Jet Hot Coat (Sterling) installed on my 355. It is peeling off after 150 miles !!!! Anybody have a similar experience? Jet Hot says " your exhaust is too hot". They are willing to recoat them (now suggesting their Extreme Sterling ), but are unwilling to reimburse me for any labor costs. Thoughts ???

 

I have heard nothing but good things from Jet Hot---Eager to hear what they consider too HOT?? How do they get to that conclusion--versus any other exhaust??

 

Hard to say, Did you ask them if would flake off before they did them for you? Did they supply you a information sheet? At least they are willing to replace the coating for you, could of have been worse

Can you Post some pics of it peeling?

 

No!! Do not use Jet Hot on headers, especially 355

 

Okay I've just been a lurker up until now, but I'm going to chime in.

I just got Fabspeed headers for my '95 355, and immediately sent them to Jet Hot to get coated. I went with the Extreme Sterling because they said they'd provide an extra 100 degrees of cooling versus their standard coating.

Yours is peeling off after 150 miles? And to the other poster on this thread, why do say not to use Jet Hot on 355 headers?

Mine are getting installed tomorrow so if there is a good reason not to use this coating (should I get some other coating?) I'd love to know now.

 

I would only replace my headers with Tubi right now as they have the right shielding combined with insulation similar to the OEM headers(except these are made better than OEM). I have heard too much bad news on these other headers. Coated or not they leave too much heat around the engine compartment and cause large problems with alternators.

 

The only problem is the Tubi manifolds are not EPA certified and Tubi Style USA is only selling them for export at present. If you can get someone to order them, around $5200, or so....but could be difficult to obtain.

Other option would be QV London, they have an exchange program so you can order a rebuilt set, and then return yours to get your deposit back. When I did mine a couple years ago, it was around $2200 or so, including shipping both ways, and all the gaskets and copper nuts. They retain the stock heatshields, CO test ports, etc. They just use a higher quality stainless steel, and go one gauge thicker.

Third option is to use stock manifolds and cross fingers.

 

Here's a novice question - can headers be replace with the engine in? It seems like there's room, just wondering how tough it is...

 

Are they peeling off near your cats or are they peeling off near your engine block?

Makes a difference.

Probably f'd up your cats either way, though...but you need to know where you are so hot as that could be an indication of a major engine problem or cat clog.

You also want to know *how hot* your exhaust is running. If it is 200 degrees over the limit, then the extra 100 degree sterling protection is just going to ruin your next set of cats.

To find out your exhaust temp, you are going to have to go to Harbor Freight and pay $20 for a laser thermometer that goes up to 800 degrees.

Use that tool while standing above your hot engine.

Report back.



*also, "labor" shouldn't be much for Jet Hot coating. They just dip them into the proper solutions and then allow to dry/cool.

 

Yup. Remove wheels and wheel liners first.

 

Coating is peeling near head on passenger side. I measured temp while hot-450 degrees or so on both sides, closer to 500 at site where peeling occurred (not surprised as coating holds heat inside pipes) . Both are WAY below Jet Hot Coating (Sterling) temp rating.

Why do you think Cats are shot?

I think the most likely issue here is improperly applied coating, not an 'engine running too hot' (peeling occurred upon engine warmup in my garage in less than 5 minutes).

By labor costs, I meant the hours I paid my mechanic to swap them !!!

 

The exhaust temps close to the head are WAY hotter than you are measuring! Maybe 500 at idle but over double that while driving.

Dave

 

I like the reasoning on these threads.
My concern is that there was an incomplete job by Jet Hot. They are willing to take them back and redo at no cost? That should provide the answer.

Other than Tubi's, what are the favorite solutions to the header problems with the 355's?

 

I have been very happy with the job done by QV London on mine. I want to say it was done three years ago and the exhausts manifolds have been fine since.

-Michael

 

+1
These coatings do not have the same thermal expansion of stainless steel. Stainless expands about 1/8" per foot of tubing length @ 1200 to 1400 degrees F. Steel headers are more condusive retaining these coatings, it expands at about 1/10th the amount of stainless steel.

I agree, the result to cost ratio of the QV fix is very good.

 

Absolutely it can be done in the car. You will need a lift for starters, along with the wheels and wheel liners, you will need to remove the under trays, and (I would highly recommend) the remote oil sump on the right side....this will require use of a VERY big wrench...as the nut for the oil line is huge. I don't recall the size, but my buddy had it when we did it, fortunately. Since you are draining the oil, you should have oil filter, 9 quarts oil, and two new copper crush washers. You will also need along with the new gaskets for mounting to the engine, 16 new copper nuts, and the gaskets that mount between the collector and the catalytic converters.

 

I am betting there is nothing wrong with his car, and everything wrong with the coating (or application process). Agreed the labor should be minor to recoat, but don't forget they will have to strip them again and prep (blast) for recoating too. Blasting them twice now, with the whatever medium they are using is taking a minute amount of metal off too...that cant' help things.

 

+1 I did mine about 2 years ago. I know of at least two others locally that did there's also with QV London. Reasonable cost, and looks stock in the engine bay.

 

YES!! If you are doing any kind of coating it is a must that you do your homework. We have seen anywhere between 20 to 30% increase in engine output with the proper use of coatings from intake systems, engine internals, and exhaust. All coatings are not the same....some are good and others will cost you big time.

If your header is coated inside and out and you are seeing spider cracks or delamination on the exterior, I wonder what the inside coating looks like??
Because of the cams used(especially in 355), there is an exhaust reversion wave that is like a dang Tsumai, which can cause any flaking metal or coatings to wind up in the combustion cylinder....and that aint good.

Dave Helms is dead on with egts' at idle(525-595). We also need to understand that the engine efficiency is at its' worst when idling, and that little aux. air pump is blowing a whole lots of air into an exhaust stream that is loaded with unburnt fuel.....guess what happens?? Remember that thermal cycling is a stress that sooner or later will become visible.


Final note, which one day I hope to post in the thread titled "355-Exposed?Covered Up? or Overlooked?"......the OEM header material is not necessarily crap...It's the design(or should I say the lack of) that is causing the problem in most of the failures.

 

Why doesn't anyone use the header wraps that are popular on muscle cars? These are cloth/ceramic wraps taht survive to 1500 degrees...

Of course this won't do anything for the inside of the headers, but would keep the heat from the engine compartment...

http://store.summitracing.com/partdetail.asp?autofilter=1&part=DEI%2D010121&N=700+4294918557+4294902309+115&autoview=sku

 

+1 good synopsis bruce!

If one uses this header wrap, one should have thick walled tubing for the higher temps the coating will generate and also enlist some form of corrosion paint or silicone coating to prevent the ambient oxygen from attacking the surface of the tubing through the thermal wrap at operating/elevated temperatures.

 

I was planning to take the old aluminum around my precats off, and wrap them with one of these "wraps", for primarily cosmetic reasons. The old metal/asbestos protectant looks lousy. Good idea? Bad idea?

 

I think they make something that can handle being wrapped around a turbo 'hot' housing. That may work, though what model f-car is this for?

 

This would be a very good argument for doing a complete leakdown before new headers are installed. Bruce is correct, if you can see it on the outside, some of the coating on the inside has now be transfered to the pistons / liners to some degree due to the reversion present. A great deal of homework must be done before experimenting in this area.
Remember, even back in the 70's we would have 1425 deg. exhaust temps on a low tech race car and bump that to 1550 deg. for qualifing knowing the engine would only last a very short time. That was before the advent of piston cooling jets. What once was the ragged edge is now every day. Wrapping the headers back then with header wrap would take a 5-8 season life span header and reduce it to about 7 races before the primary runs would blow out. There is a lot more going on in there than most folks realize.
Bruce and I are working on the same theory (with as much time as we have spent on the phone, one would think we should have solved all the worlds problems by now) and I now have more data to support we are going in the right direction. As I am dealing with customer cars, I have to have great amounts of hard data to support any theory and subsquent changes to a design before it makes it on a car. Make that 4 yrs of data collection so far with my first 4 theorys being disproven. Dyno data collection is a very small facet of what is needed here. Longevity of all components, before, after, and including the headers, must be thought through completely before any changes are made. There is a lot at risk here!

Dave

Dave

 

My Coated Fabspeed headers of only a few months are peeling in the EXACT same place on the EXACT same header (passenger side).

I need to call Jeremy... I PRAY the insides of these headers weren't coated. If they were, this could explain all of the CELs I've received since the install. The dealer hasn't been able to find the cause of my 0422, 0432, 1445, 1449, and 1448 codes; none of which existed before the headers and could suddenly make sense if these headers were coated internally.

--Nick