Ceramic coating pistons

[anonymous-user]

Whilst APM have my 4.5 for a rebuild, I've been looking around for other things to do to the engine while its out, does anyone have any knowledge or experience of ceramic coating their piston crowns and/or liners and/or valves, either on an AJP or other engine and if there are any subsequent ignition issues, compression ratios problems etc?

Also read that teflon coating the piston skirts (if I don't need new pistons) to ease friction in the liners at same time, I saw a short article on Racing Greens website, but it only related to the S6 engine. Does this coating last or are there alternatives now as the article was from 2008?

Ceramic coating the crowns looks a pretty cheap thing to do whilst the engine is apart at about £30 per piston crown, so just weighing up pros and cons.

[hiltonig]

I had mine done by camcoat, they did the pistontops and skirts, also had the pins done and the combustion chamber and valves on my 5.4 rv8 engine

[anonymous-user]

hiltonig said:

I had mine done by camcoat, they did the pistontops and skirts, also had the pins done and the combustion chamber and valves on my 5.4 rv8 engine

Any problems with compression ratio or ignition at all? A few articles I've read indicate that the ingition timing becomes rather more critical due to the lower chamber temps.

I probably wouldn't go that far, but protecting the piston crowns and reducing power loss thru friction is appealing.

[hiltonig]

Not sure if the benefits are measurable but it makes sense in someways to do it at engine assembly stage. Every little helps in a performance motor.

[Steve_T]

Not sure how the temp would be going down in a chamber when the piston top is now covered in an insulator. It should mean that there is less surface area through which heat can be dissipated, hence the in cylinder temperature should be up. By how much I've no idea.

[anonymous-user]

Steve_T said:

Not sure how the temp would be going down in a chamber when the piston top is now covered in an insulator. It should mean that there is less surface area through which heat can be dissipated, hence the in cylinder temperature should be up. By how much I've no idea.

No no with just coating the crowns the temps wouldn't go down I agree, the liner would then effectively have to dissipate "more" heat as you say, but Hiltonig has basically coated the entire chamber as well as the crowns.

[Gazzab]

My engine had some coatings applied last week at Chesman Enginering in Coventry.

[Steve_T]

djstevec said:

No no with just coating the crowns the temps wouldn't go down I agree, the liner would then effectively have to dissipate "more" heat as you say, but Hiltonig has basically coated the entire chamber as well as the crowns.

My understanding was the use of coatings was to reduce the heat loss and hence increase the cylinder pressures - makes sense that this may have an effect on the required ignition timing but I don't know for sure. May be a good general question for the engines and drivetrain forum if it catches the right folks attention. Looks like it gets some good results as a quick google gave: http://www.swaintech.com/store.asp?pid=10321

Edited by Steve_T on Thursday 22 March 14:39

[Nickccc]

I guess since your looking at the bits you have mentioned you will be balencing the crank rods and pistons anyway.
Im not that up on ceramic coating though have heard of DLC coating, I would have thought the buckets, cams, rod pins and anywhere else where friction could be reduced will see gains, friction and out of balance components will all sap power.

[anonymous-user]

Steve_T said:

djstevec said:

No no with just coating the crowns the temps wouldn't go down I agree, the liner would then effectively have to dissipate "more" heat as you say, but Hiltonig has basically coated the entire chamber as well as the crowns.

My understanding was the use of coatings was to reduce the heat loss and hence increase the cylinder pressures - makes sense that this may have an effect on the required ignition timing but I don't know for sure. May be a good general question for the engines and drivetrain forum if it catches the right folks attention. Looks like it gets some good results as a quick google gave: http://www.swaintech.com/store.asp?pid=10321

Edited by Steve_T on Thursday 22 March 14:39

I was reading the same website earlier! :-)

My main reason is that the piston isn't cooled in any way, so would reducing the crown temp keep them in better shape for longer? Camcoat claim their reflective coating also helps to keep the crown freer from carbon deposits.

[Steve_T]

Can't hurt but it depends on your budget for the rebuild. Compare it to where else you might direct your funds as it's not done as standard and the engine still produces plenty of power.

[Nickccc]

If its piston cooling you are after why not see if you can install oil squirters. Ages ago I spoke to the guy who does the Tuscan Challenge engines and he mentioned it had been done before.

[ukkid35]

Nickccc said:

If its piston cooling you are after why not see if you can install oil squirters. Ages ago I spoke to the guy who does the Tuscan Challenge engines and he mentioned it had been done before.

Both my other cars have piston squirters, the disadvantage is that you increase foaming/windage and potentially suck a lot of oil through the crankcase breather, and then there's the chance of detonation - on an engine without knock sensors.

[Nickccc]

Maybe give that a miss then.

[a1rak]

I would only recommend coating brand new unused components and only if there is a known isssue on an engine such as heat soak when the engine is switched off. Coating used components could cause a whole host of issues as the coating seldom takes properly and engs up contaminating the engine despite what the coating company says.
I would look to spend your money elsewhere such as a pre-oiler or accusump, and or possibly an electric water pump to circulate after the engine is switched off.