Turbo exhaust housing blanket or ceramic coating?

[starscream5000]

If you want chrome ceramic coated parts that are done proffecsionally, PM JDub, he has done numerous parts for me. His ceramic coatings are good up to 2000K degrees and it will turn a titanium color on your turbine housing and other hot parts. Tell him I sent you and he should be able to give you a good deal on coating the hot side (and the cold side if you want) of your turbo. If you want superb protection, get it coated from JDub, then put the turbo blanket, or a heat shield over it. The hot exhaust gases, in theory, will travel out of the turbo and exhaust faster due to the radiant temps staying inside the exhuast itself, thus creating a better scavenging effect.

 

[CFSapper]

And if there is a debate on this I'll pay to see someone put their hands on a coated turbine housing seconds after boosting hard while the car is running!

how mu im short on cash right now and have done stupider things

 

[Sawbladz]

Since you guys are talking about ceramic coatings I thought I would just post here. Does anyone have anything on their car ceramic coated that hasnt turned grey? I want to get it done for the thermal advantages but I also want it to look good.

My friend has Fireball coated headers that were glossy at first but now are a dull grey...and thats at N/A temps...not turbo. So this is not the option for me.

Does anyone have any advice or personal experience with ceramic that stays shiny?

Thanks

 

[jdub]

Sawbladz - The ceramics I have experience with (a 2000 deg rated) will turn a titanium gray. That is due to the content of the formula...it uses titanium in a ceramic matrix for the thermal properties. That is a problem with polishing and real chrome as well....polish will turn dull quickly and (unless it's stainless), will oxidize. Stainless will dull to a golden color...real, heavy chrome plating turns blue.

The heat coming out of a turbo is in the 1400-1500 deg range...the ceramic can handle it (no flaking, chipping, cracking, etc) but reverts to more it's "natural state". This happens only on very hot parts...exhaust manifold, turbine housing, downpipe. Heat shields, even in close proximity, will stay shiny using the ceramic. Any other part in the engine bay that's ceramic coated will also stay nice looking.

Pros & cons of ceramic vs. turbo blankets:
- Ceramic has excellent thermal resistance...exhaust parts should be coated on the inside for max effect. No more rust, but even hi-temp ceramics will loose their luster. As pointed out, the part will still be very hot to the touch, but will not radiate as much heat as a non-coated part. The parts will cool fairly quickly on shut down.

- Turbo blankets will cut down on radiated heat even more than a ceramic. They will deteriorate over time from the heat. They also retain heat and moisture after engine shut down...this can cause rust. I highly recommend a turbo timer even using syn oil when using a blanket to allow some cool down. You have to be careful about any sudden cooling effects for a longer time due to the heat retention to prevent metal fractures. Heat rention can cause steel to lose it's temper...usually not a problem for exhaust parts.

- Best is the combination...both a ceramic and blanket. A huge reduction in radiated heat will result with this combination. Wrapping the downpipe after it's ceramic coated will basically have the same effect. Both will benefit from the sealing effect of the ceramic...moisture under the blanket or wrap will not cause oxidation. Have your manifold heat shields ceramic coated as well.

 

[chriso]

So jdub, are you the resident ceramic coater guy I've been thinking about????

 

[chriso]

I found this while doing a search about tech line coatings. This looks like really cool stuff. Anyone care to debate this?
http://www.appliedplastic.com/BlackSatintest-1/

Thanks for the input on blankets Duane and Qwikstrike.

 

[jdub]

Chriso - That would be me

That link you posted looks like a black ceramic...the temperature drops are about the same as I have seen on exhaust parts. Black is more effective at cutting radiated heat...about 10-20 deg better. I have done black, but it's more expensive than the chrome...about 20% more. If you are looking at ceramic coatings, stay away from Jet Hott for exhaust parts...they will tell you it's a hi-temp ceramic, but I've seen it flake off. Not good inside for pre-turbo. Cermakrome is a good product, appears to perform as advertised. The stuff I use is a mil-spec formula, polished with a ceramic bead polisher.

The stuff you buy in a can and apply at home might be good for your grill, but there's no way I would use it on my exhaust. A true ceramic has to be applied to a very clean metal surface (bead blasted) and cured at 500 deg. It requires specialized spray equipment to apply it.

 

[QWIKSTRIKE]

Sawbladz - The ceramics I have experience with (a 2000 deg rated) will turn a titanium gray. That is due to the content of the formula...it uses titanium in a ceramic matrix for the thermal properties. That is a problem with polishing and real chrome as well....polish will turn dull quickly and (unless it's stainless), will oxidize. Stainless will dull to a golden color...real, heavy chrome plating turns blue.

The heat coming out of a turbo is in the 1400-1500 deg range...the ceramic can handle it (no flaking, chipping, cracking, etc) but reverts to more it's "natural state". This happens only on very hot parts...exhaust manifold, turbine housing, downpipe. Heat shields, even in close proximity, will stay shiny using the ceramic. Any other part in the engine bay that's ceramic coated will also stay nice looking.

Pros & cons of ceramic vs. turbo blankets:
- Ceramic has excellent thermal resistance...exhaust parts should be coated on the inside for max effect. No more rust, but even hi-temp ceramics will loose their luster. As pointed out, the part will still be very hot to the touch, but will not radiate as much heat as a non-coated part. The parts will cool fairly quickly on shut down.

- Turbo blankets will cut down on radiated heat even more than a ceramic. They will deteriorate over time from the heat. They also retain heat and moisture after engine shut down...this can cause rust. I highly recommend a turbo timer even using syn oil when using a blanket to allow some cool down. You have to be careful about any sudden cooling effects for a longer time due to the heat retention to prevent metal fractures. Heat rention can cause steel to lose it's temper...usually not a problem for exhaust parts.

- Best is the combination...both a ceramic and blanket. A huge reduction in radiated heat will result with this combination. Wrapping the downpipe after it's ceramic coated will basically have the same effect. Both will benefit from the sealing effect of the ceramic...moisture under the blanket or wrap will not cause oxidation. Have your manifold heat shields ceramic coated as well.

Totally the best way to go. I was going to get my exhaust manifold coated but if it cracks it would be hard to find and have to be recoated!

 

[jdub]

The ceramic coated exhaust manifolds I've seen crack was due to a poor coating job on the inside (or not coating the inside at all). It also depends on the manifold...tube type turbo manifolds will crack at the welds, inside the bends, or turbo flange.

There are 2 different type stock manifolds. One has round runners and will crack between the runners or next to the turbo flange...neither place is good (exhaust leak) and the manifold will have to be replaced. The 2nd is on later model 7M turbo motors ('90 up ?)...it has reinforcement ridges on the top of each runner and is thicker overall, especially around the turbo flange. The only cracks I've seen on this type is on the turbo flange itself, usually pretty small and do not cause a leak issue. The steel turbo gasket seals outside the crack anyway and the metal is thick enough to stop the crack...it's almost impossible for it to leak in this location. If you are using a stock manifold, this is the one to have.

Every manifold (regardless of type) I've seen that was properly coated on the inside did not crack...I've done at least 25-30 of the various types. This is the biggest challenge in doing it yourself...getting the inside coated properly. Plus the curing temp must be above 500 deg. Otherwise, you risk chipping or pieces of ceramic flaking off and heading for your turbo blades. IMO, a 2000 deg rated coating is the only way to go on exhaust manifolds and turbine housings...for the same reason.

Just coating the outside is just as bad, that can cause the manifold to crack...I will not do a job for someone that wants just the outside coated to save a few $$$ due to this reason. Don't want my name asociated with something I know is going to be a problem

 

[Sawbladz]

Thanks for the info. It looks like I will have to deal with the dull grey and save the shiney stuff for intake parts.

Since I'm in Canada, I think it would not make sense for me to get my parts done by you. Just too far to ship all that heavy stuff. Would it be common knowledge for the person doing the coating to do both the inside and the outside as well as bake at 500 degrees? Or would I have to give them step by step instructions.

 

[mattjk]

jdub, how bout a group buy?

 

[lintlars]

Ya what he said^^^^^^GB

 

[tissimo]

When I got single on my 2j, im going to ceramic coat everything and then maybe get a blanket as well.. or maybe one of those bling bling hks turbo heat sheilds..

 

[mmarkk]

The ceramic coated exhaust manifolds I've seen crack was due to a poor coating job on the inside (or not coating the inside at all). It also depends on the manifold...tube type turbo manifolds will crack at the welds, inside the bends, or turbo flange.

There are 2 different type stock manifolds. One has round runners and will crack between the runners or next to the turbo flange...neither place is good (exhaust leak) and the manifold will have to be replaced. The 2nd is on later model 7M turbo motors ('90 up ?)...it has reinforcement ridges on the top of each runner and is thicker overall, especially around the turbo flange. The only cracks I've seen on this type is on the turbo flange itself, usually pretty small and do not cause a leak issue. The steel turbo gasket seals outside the crack anyway and the metal is thick enough to stop the crack...it's almost impossible for it to leak in this location. If you are using a stock manifold, this is the one to have.

Every manifold (regardless of type) I've seen that was properly coated on the inside did not crack...I've done at least 25-30 of the various types. This is the biggest challenge in doing it yourself...getting the inside coated properly. Plus the curing temp must be above 500 deg. Otherwise, you risk chipping or pieces of ceramic flaking off and heading for your turbo blades. IMO, a 2000 deg rated coating is the only way to go on exhaust manifolds and turbine housings...for the same reason.

Just coating the outside is just as bad, that can cause the manifold to crack...I will not do a job for someone that wants just the outside coated to save a few $$$ due to this reason. Don't want my name asociated with something I know is going to be a problem

jdub, what's your opinion on coating a ported stock manifold(later 'reinforced' model) ?
thus making it thinner, it has more chance to crack even when coated inside and outside?

 

[Adjuster]

Coatings or blankets and wraps are good alone, but as noted, together they are an awesome combination to fight underhood heat.

My coatings experiance has been mostly with Techline coatings, and they have held up very well.

The powder coating I've had done has also held up well.

The Latest setup is a custom modified Ebay manifold, MPT-70 turbo and everything is coated and wrapped. (The hot side blanket is in the plans.)

My DP is wrapped to the cat back, and it's coated too. The underfloor heat is substantially reduced even on very hot days after running at very high speed, and working the engine/turbo quite a bit.) The floor used to get too hot to touch at times in the summer. Now it's hard to tell it's any hotter than any other part of the floor.

Same with the transmission. (You notice your DP runs along your trans? Well your heating up the oil in there will all that radiant heat, so the coatings and wrap keeps it mostly out of the trans.) My trans is also coated with a thermal dispersant inside and out, and any friction parts are molydisulfied coated too. (Forks, bushings and thrust washer etc.) The coating helps to radiate heat from the trans to the airflowing over it as you drive. My shifter does not get hot anymore. Again it used to be too hot to handle at times in the summer, but not anymore.

The next round will be improving the air flow over the radiator/FMIC and other coolers, and venting the hood and possibly the fender to relieve as much underhood air pressure as possible. (And thus draw as much air across the coolers as possible while keeping front end lift to a minimum at high speeds.)

Nice links on the Hot side blanket. Anywhere it's sold for less than 150.00? That seems sort of steep considering it's just a truck part?

 

[chriso]

My coatings experiance has been mostly with Techline coatings, and they have held up very well.

So what is your final opinion on Techline stuff. Did you do it yourself?

 

[jdub]

Thanks for the info. It looks like I will have to deal with the dull grey and save the shiney stuff for intake parts.

Since I'm in Canada, I think it would not make sense for me to get my parts done by you. Just too far to ship all that heavy stuff. Would it be common knowledge for the person doing the coating to do both the inside and the outside as well as bake at 500 degrees? Or would I have to give them step by step instructions.

Yeah...shipping is rather prohibitive to Canada, considering the size/weight of the parts we're talking about. I would definitively talk to the guy you choose about coating the inside. If a ceramic is used, I certainly hope they cure it at that temp.

jdub, how bout a group buy?

I'll have to think on that one.
The problem with me is the time...the AF Reserves have been keeping me kinda busy lately.

jdub, what's your opinion on coating a ported stock manifold (later 'reinforced' model) ?
thus making it thinner, it has more chance to crack even when coated inside and outside?

Porting it should not be a problem. The areas where you will remove material is not in the typical "crack" areas, especially for that manifold. If you remove the humps on the inside where the studs go, make very sure you use a copper or nickel anti-sieze on the threads to seal the stud. Be careful about porting the head side...pay attention to the hole size relative to the exhaust outlets on the head. It's preferable to have the outlet from the head a little smaller than the inlet to the exhaust manifold. This "mismatch" creates an anti-reversion dam that inhibits the exhaust gas from trying to sneak back into the cylinder when the intake valve begins to open as the exhaust valve is just closing.

 

[tekdeus]

Bumping for more feedback and experiences. Also, the center(CHRA) on my custom GT35r is sunk deep into the T4 housing, making the oil and water fittings actually touch the bolts on the turbine housing. I want to put a turbo blanket on it, but it would have to cover the water and oil lines. Any risk doing it this way?

Any alternative sources for turbo blankets? I can't seem to find much in the way of T4 metal heat shields either.

 

[foreverpsycotic]

A metal shield will most likely have to be bent specifically for your setup.

 

[Poodles]

HKS makes sheilds what work on any setup..