saccitycorvette

iTrader: (3)

Hi,
Has have any of you done your own piston coatings on the top and skirts.
Have you used Techline Coatings like CBX for top of piston and DFL 1 for skirts?
What do you think. I hear there are some good advantages to coating to pistons.
Have anyone had any issues?
Thank you,
Chrsitian

JL ws-6

iTrader: (50)

Always used the coatings that Diamond puts on their pistons, which I believe is done at Dart. Skirts and a top coating for heat.

The pistons I have seen with the coating on the sides, the cylinders always seem a little better than when you don't. As for the top piston coating, it won't stop you from burning one, but it might save you once or twice.


There is another coating out that I can't remember the name of that actually gets put on to the point of an interference fit and is designed to wear into the bore quickly, this is designed to stop piston rock, and supposedly makes a substantial improvement, but I can't recall the name of it for the life of me. It's relatively new, and has been tested in the motorcycle roadcourse world a bunch with really good results from what they claim.

I have not used this, nor do I know anyone that has, but I do plan on having my engine builder look into it when I have my motor apart for upgrades, or build my next one whichever I end up doing.

96 Comp T/A

iTrader: (8)

I have used the Techline stuff before and applied it myself, although not in an LS application. It certainly worked in our application. Back to back testing on the dyno was on the order of a 5% increase in power output, however engine in question was air cooled, and a thermal sieve, so anything we could do to contain that combustion energy was a positive. I have had Dart do the pistons in my current engine, and will likely have them do any future engines I build.

patrick335d

If i remember correctly we used Molykote D321 on the skirt of the piston.

KCS

iTrader: (20)

I've used Polydyne for coating skirts. The bores would have to be honed a little on a refresh and if the customer didn't want to buy new pistons, Polydyne would apply a coating to reduce the piston-to-wall clearance. It's worked great with no excess noise.

Krom

I've used swain coatings on lots of 2 stroke stuff
http://swaintech.com/race-coatings/

The exhaust coating really does work. The piston coatings would let me run much higher egt's

c0ncEpT

iTrader: (4)

All coatings Diamond offers are done in house. (Moly skirts, Ceramic tops, Anodize)

Also the interference fit coating your referring to is an APC coating done by Line2Line

JL ws-6

iTrader: (50)

Dart misdemeanor the coating for diamond years ago, good to hear they do it in house now.

The line to line coating is correct that's the interference stuff that was developed in super bike applications. It would seem to make a lot of sense to put to use in a drag engine, but I don't know anyone with first hand experience

thompson

iTrader: (4)

It can certainly be done with success but be careful on bore size. We have had a few people send in attempted home coat and build motors that have been a bit on the tight side and caused some catastrophic results.

The diamond coatings are great. We have built motors with several thousand sets and they are mixed coated and non coated. We have noticed that the coated skirts do have a cleaner cylinder wall after a season of racing but also noticed that on a daily driven vehicle the coating depletes rather quickly so the protection on a driver is relatively short term.

kingtal0n

iTrader: (1)

I'd love to know which coating offered protection for long-term daily driver applications. Something we can use on a forged piston to help with cold-start clearance perhaps? Definitely don't like the way they rock when the piston/wall is large. But besides that, I'd like to cut down on the bore wear (often see streaks down the sides after 100k miles)

c0ncEpT

iTrader: (4)

The Line2Line APC is the way to go. Its going to be the most durable coating.

The moly based skirt coating Diamond and other manufactures apply is a sacrificial coating designed for initial break in protection really. It will wear away in engines that see a lot of run time.

JL ws-6

iTrader: (50)

It would stand to make sense the line to line coating may almost need a piston with a touch more clearance to be effective though no?

c0ncEpT

iTrader: (4)

The coating is designed to wear into where the piston is happy in the application/power level.

As a piston manufacture your consistently trying to run them as tight as you can without sticking them to help reduce piston rock. With that being said they're going to air on the side of caution (loose) every time.