How about friction coatings....anybody try em?
 

www.calicocoatings.com and www.casidiam.com have coatings to help reduce coefficient of kinetic friction. Note, this is not a thermal barrier product. Anybody have any experience with these??

Jaime

The objective is to....?

We use calico for coating our pistons and doing the chambers and ports on our heads. Anatech (which is the developer of Casidiam) makes a great product. We've used it on cams, valves, lifters, rocker shafts, rocker faces, pushrod ends- you name it, we've tried it. We've even used it on valve stems and seen an appreciable reduction in wear and temperature. When trying to push the limit or seek the ultimate in longevity, both companies provide killer services.

...........reduce coefficient of kinetic friction...?

Jaime

Help me -- I'm not an engineer. What does friction in Connecticut have to do with our 911's? ;) What's the objective. Increase HP? reduce wear? improve reliability? Reduce lap times? Reduce operating costs? Reduce wallet weight?

Just because it provides 15% improvement in efficiency (as they often say on Star Trek) doesn't necessarily mean that it provides a performance gain nor make it a good investment.

I'm not knocking friction reducing coatings -- just trying to understand the "problem statement" that friction reducing coatings is the answer to.

Primarily reduce friction and wear when it comes to the Casidiam coating. It was originally pioneered years ago for use on Ti valves to make them actually wear at a normal rate. Similar technology is currently being put into production cars with the new Z06, which has Ti valves :-) Although cost prohibitive, they have taken nikasil cylinders and further casidiam coated the bores to further reduce friction. Saw it in action at the PRI show a few years back. Does that help?

Hi John. As Charles states, it adds few microns of a harder, though thin, coating that changes the surface of metals, sort of like coating with diamond if you will. Theoretically, it should impart a longer lasting, slippery characteristics that act against friction which is what eventually slows our engines and also "ages" them.

Jaime

Problem statement - My 930 motor is air and oil cooled and is very expensive to rebuild. Although it is reliable, heat can significantly reduce engine life and horsepower.

By coating the piston skirts, I have decreased its coefficient of friction, thereby lowering heat and making the four stroke process a bit more efficient. I also had the piston domes ceramic coated to guard against detonation damage and reflect heat. Heat disbursant coatings to the outside of the cylinder helps move heat away from the top third to the rest of the cylinder.

Was it worth it? The ceramic coating seems to have helped the detonation thing, since my motor burned up a couple of months ago with no distortion to the pistons or ring grooves. I think it cost me $25 each to have the pistons dry lubed and ceramic coated. I did not see the value in coating the springs, rockers, and so on.

The Casidiam procress (also known as DLC- diamond like carbon) is a only a few microns thick- non-dimensional, whereas the coatings from Calico do add a measurable thickness, usually a minimum of .001". The only coating that I have not seen a measurable improvement on has been the thermal dispersants except on cast iron.

OK. I wasn't trying to be a "dick" -- although it may have sounded like it. Often people (especially newbies) post "solutions", like -- "Anyone try the new cool coller from XYZ company to reduce engine temperatures???". The answers are often just as vague: "Sure, been using it for 10 years and my engine runs great! The best things that ever happened to Porsches!" The end result is zero shared learning by the Pelican Community.

General questions often result in general answers and repeated conventional wisdoms. You get those sort of things from any number of sources. That's why I was trying to push you a little bit to be more specific. Is your application street or track? DE or competition? For use on springs or pistons? Is there a specific problem (I'm spending $X replacing valve springs every month) or is it a "Gee this is neat" engine improvement? This helps to focus the responses a little bit and get you a better answer. For example notice that a couple of the responses were regarding the thermal coatings rather then the friction coatings like you asked.

My apologes for not coming across well. Welcome to the board -- we're not always this difficult. At least I'm not! SmileWavy

BTW - What sort of car do you have?

Hi John. No appologies needed and I didn't think you were being a di_ _. I've read how formula one had a new trick up their sleeve some 15 years ago and thought to myself that one day I'd like to check this out (ceramic and friction coatings)on a special sports car. Now you can get almost any metal treated and is no longer a secret.

My car is a 1993 America Roadster that has a transplanted engine/trans/AWD/brakes from a 1996 993tt. It has JIC Cross all four corners, RUF ecu/cams/130mm, 100cell cats. I'm getting the entire exhaust ceramic coated by Swain technnologies in NY. When I need to get into the case I'd like to check out these friction coatings and just wanted to see what people here thought of them.

Thank you for the welcome.

Jaime:)

I didn't take it that way either - sorry my post was worded the way it was.

I thought you were a di_ _ !:) Just kidding! I have looked into coatings as well and read a few threads..... I am just not sold on them yet, not sure why. Does anyone know if they will "save" an engine or how much increased life one can expect out of the coated parts as compared to uncoated similar parts used in the same manner?

Cheers,

Jeff,

One coating I have seen time and time again prove itself in race situations is Calico's bearing coating. I even had a customer who could not get bearings in time for a race engine and had his trashed used bearings coated and it got him through the weekend and even afterwards the bearing didn't look all that bad. There are guys here locally that I know that run blown alcohol drag engines 2400-3000+ hp and they religiously coat everything but even then when their high-speed lean out triggers with too much advance at 60lbs+ of boost, there's not much you can do to save things. :-)

DonE's problem statement is a good explaination for the WHY- "My 930 motor is air and oil cooled and is very expensive to rebuild. Although it is reliable, heat can significantly reduce engine life and horsepower."

Probably the most applicable coating to the 911 would be the casidiam coating on the valve stems which reduce wear and lower temperatures. This reduces over time the smoking caused by worn guides and in essence can get you further without having to do a top end rebuild.

Coating the bearings would provide a secondary lubricant for cold start ups and momentary loss of lubrication and also protect from scuffing during low pressure situations (hot oil at idle?).

Thanks, that is good info.

CHeers

We use dry film lubricant on all bearing, cams and rockers.
The goal is less friction, resulting in lower temperatures and less wear. Results are less wear, lower operating temperatures and one other unintended consequence, higher oil pressures.
Go figure?
Draw backs? none that we see.

Reduced friction also means MORE POWER!. Friction, esp ring friction is the main loss in an engine. Anything that can reduce it is welcome.

They have been around for years (coatings) thet do work and there several types from tafelon to some sort of moly,personaly I never put a eng to gather w.o. it anymore as the extra ins is worth it. I am not talking just P. eng either,but big exp diesel stuff to handgranade Harly eng.
On the diesel its nice to have a heat shield on top and moly sides as it makes it all quieter and the e.g.t can go past the red zone w.o. a melt dwn-same is true for our little P. eng.

On the diesel its nice to have a heat shield on top and moly sides as it makes it all quieter and the e.g.t can go past the red zone w.o. a melt dwn-same is true for our little P. eng. [/B][/QUOTE]

You mean ceramic coat on the piston tops? How about the combustion chamber and valve faces?? Do you do these too?

Jaime

I dont do it all but send them to my vendor on E.coast, as far as ports and heads it will depend on aplication of how much and where you need it.
And yes ceramic the tops

Oh, BTW, anybody ever have a turbo damaged from pieces of coated piston tops/combustion chamber peeling off and exhausted down to the turbos impellers? Sounds risky if you have turbos down there waiting to "filter" those ceramic chunks!!

How 'bout it Mr. Navarro or anybody

Jaime

NO,this is proven stuff guys,not snake oil, do some home work you will see the light

Never have I heard of the coating flaking off unless the parts are not prepped properly. I had a small outfit out of oregon do my personal heads on a 914 engine and they didn't prep them right and all the coatings could be removed with just a fingernail- it was that bad. That's why I don't recommend doing them at home, although I have tried stuff like the techline thermal disperants and done them myself with excellent results. But again, that's an external coating that won't hurt anything if it does fall off. Inside the engine, that's a totally different story. I'd leave it to the pros- Calico or Swaintech. There are others, but I like the comfort that these two companies do the majority of race components regardless of industry. I've also spoken to them personally at the PRI show and have faith in their processes and services. Never have I had a problem with either.

Hold the press!! I just got back my headers from Swain. They did a great job of applying the ceramic on the exterior......BUT, unfortunately (?) they also purposely sprayed the inside of each header as well as the collector at the other end, prior to the turbos! I spend a good amount of time cleaning up welding material and sanding the interior of the headers only to get them back coated. They have effectively decreased the diameter of my headers...should I send them off to get them extrude honed? Do you think it matters on a turbo engine?

Jaime

I personally think that the coating on the inside should help the headers last longer and won't decrease the flow. If anything, the coating should be fairly slick. As long as they didn't coat any sealing surfaces. Those I would have bear metal unless someone thinks otherwise. Suggestions?

How thick is the coating that we're talking about? What % of the total cross-sectional area did you lose? I've heard of people purposely using smaller cross-sectional headers to decrease the total volume upstream of the turbo. This was supposed to decrease turbo-lag since the engine doesn't have to pump up as large of a plenum volume prior to the turbo spinning up.

For a turbo aplication, I never coat the headers inside, the material (mild steel,stainless,etc.)expands and contracts too much, and it is prone to flake out ,plus if it get striked by an object it may crack inside,imho it is a no-go.,cheers,Antonio.

as to how thick....will very from vender to vender and "where it is being applied. Pistons will be very small (so you do not have to add multiply and subtract for the bore)

Antonio made a good point on coating the insides for a turbo application being a minus if flaking were to occur. I always forget when we switch our discussions between n/a and forced induction that I have to change my way of thinking, since I deal mostly with normally aspirated where it really doesn't matter if it were to flake off.

I typically never coat skirts on the pistons if the proper clearance has already been set up. In most cases, we're running .0015" total piston to cylinder clearance and the skirt coatings start at .001" thick on diameter, so you can do the math. You end up with a piston that either can't be loaded into the cylinder (or) it's too tight, regardless of the fact that the coating will scuff and wear off upon break-in.

Jaime,

Coating on the inside of headers is certain NOT to affect the flow in any way, period. GIve me a break, out of the total area of a header, the coating is so insinigficant as to be assinine to even talk about. The subject of flaking off is another matter. THe coating may very well flake off, (highly doubtful if applied correctly) but will it do any damage??? VERY VERY doubtful.

Sorry for the choice of words, but I couldn't think of anything more fitting. I bet you cannot even CALCULATE the decrease in flow, let alone measure it, and thats assuming its a decrease! As bad as saying that you can get 10,000 percent increase in power with headers.

As to the benefits or lack of for coatings, lets put it this way. The BIG BUCKS guys of NASCAR all use them, extensively. Why? because they DO NOT WANT TO WIN?? They use them, because, used intelligently, they work, and work well. Swain Tech has some good info in how they work. And if you go with a coating only go with one of the two companys that work. Swain or the second best.

For me HPC is the only one that I use.Cheers,Antonio.

Gawleee, snow....I feel b*tch-slapped ;-) I have no problems accepting these coatings as helpful adjuncts, but I did have a question (note the "?"on my post) regarding its use inside the header. To think there is no delta from having the inside coated with a measurable thickness, no matter how thick is plainly careless. Maybe its splitting hairs, but even NASCAR would have studied the effect on performance due to the reduced lumen diameter......trust me!

Antonio brings up a very valid point.....thermal expansion. With heavy heat cycles between hot/cold there will be room for at least partial coating failure. If or when this happens, there will be an expensive filter (turbo) to catch the clumps. This wouldn't be a problem for NA engines, but I'd rather not take a chance with a turbo engine. I'm going to make arrangements with Extrude Hone to help me out on this one.

Jaime

At least that way you'll know the insides are nice and smooth :-)

What about those little chunks of carbon that flake off the cylinder and piston? If they do not trash the turbo, its very doubtfull that paper thin specs of coating, not chunks, will do any damage. Furthermore any specs of coating cannot get into the turbo bearings via the exhaust system. Typical coatings are only 1 to 3 thousands of an inch thick, not a source of "chunks". Flakes maybe, but flakes that are very fragil and would easily pass thru a turbo. The tolerance for making header pipe is much greater than the total thickness of any coating. If the coating thickness were enough to hurt the flow, the extrude hone process will certainly damage the flow, as the pipe inside diameter would end up being to large. But it won't because it isn't that critical.

Maybe I was a bit harsh, but understand that coatings are at the most like a coat of paint, and thats the thickest ones. Most are so thin that they do not even affect the dimensions of the parts that are coated. Even the coatings that many beleive wear off, like on piston skirts, are still effective even though only a microscopic thin layer remains after a couple of thousand miles..

You have a point regarding flake vs chunk.....at the heat collector of the header, where the heater ducts connect, they also sprayed all around. Because the ceramic was sprayed onto a thin edge there is some cracking right at the edge. I was able to peel off with my finger nail maybe a 2X4mm "flake" off and let me tell you that a turbo with clipped impellers, seeing upwards of 175K revs/min will see this flake as a chunk. I've seen carbon flakes...literally like the flakes one feeds goldfish. Very light almost transluscent. Swain is thick. maybe 2-3 sheets of paper thick. They even let you know that's what sets them apart from other companies doing the same. Lubrication seals is not the worry, its the blades that come in contact with this flake that would impart enough energy (loss of momentum) that it could unbalance it. Anyway...best not to have anything waiting to happen.

I do appreciate all the shop talk though, makes it fun. All we need a beer or two.

Jaime

I while back I was playing with water injection, injecting water before the compressor, and belive me after a while even the water eroded the compressor tips,as Jaime stated,is not the size of the chunk but the force and velocity of it that matters.,cheers, Antonio.

Can I say something..WILL you listen to Snoman!! and tune in. the stuff on my pistons I believe is about 2/10 of thou. maybe once in awhile a flake will come off...not like water running strait threw.............This application has been around for along time.....Give it up already!

LOL, Afterburn....did you read my entire post, three posts above this one? Swain Tech ceramic coat is NOT, NOT, NOT thin!

But yeah, let's let it rest now.

Jaime

I'm not talking about coatings on pistons,cyl head,etc, I'm just saying that coating the inside of headers for a turbo aplication is a no-no.