reducing heat from turbo.

[T77911S]

i was putting my muffler back on and trying to figure out how i could reduce heat transfer from the turbo. my dist gets so hot i cant even touch it.
so i was wanting to add some more heat shield so i did this below. but my other question was about the oil line that runs to and from the turbo. why not wrap it in something like that exhaust manifold wrap? that could drop the oil temp going into the turbo considerably, no?
anyone ever try it?


this heat shield is small but i hope it helps.

[guru944]

T77911S:

The Heat topic is the always a challenge for all of us. However these companies have developed excellent solutions to better manage the thermal energy radiation which unless resolved wreaks havoc on our vehicles. I have used a few products from each and even combined some for optimal cost and protection. Successful to 90% reduction. They do work well...

Swaintech 3000 White Lightening is the best ceramic coating i have ever used.
Gold foiling works but is very expensive.
Black Thermo-wrap is cost effective.
DEI GEN-II Turbo Shield is awesome.
Stealth Turbo Shield by Heatshield Products Inc.

DEI : Exhaust Header Wrap, Thermal Performance, Acoustical Control Products, Cryogenic Intake and Nitrous Systems | Design Engineering, Inc. DEI CryO2 Ny-Trex Boom Mat SPA Turbo USA
Swain Tech: Swain Tech Coatings | Industrial Coatings | High Performance Racing Coatings | Technical coatings to solve problems of heat, wear, corrosion, and friction
Thermal Control Products: Thermal Control Products | Thermal Heat Solutions
Vibrant Products/DCI PP: Vibrant Performance ::.
Heat shield turbo Shield: Exhaust Wrap, Heat Shields, High Temp Insulation | Heatshield Products

Hope this was helpful...Later.

[TurboKraft]

If you really want to control heat, skip the turbo blankets. 930s cook them, we have a box of failed ones as proof. Air-cooled Turbos are like rotary engines in that our exhaust temps are much, much hotter than you typically find on water-cooled engines. These flexible blankets -- regardless of lava-this-or-that material -- just don't hold together.

The rigid foil-covered ones are better, but you're still allowing the turbine to radiate heat -- the foil shield is just deflecting it.

Remove the turbo and have the turbine housing thermal barrier coated with a coating rated for 2,000F or better. The typical 1,300F or 1,600F coatings won't last. BTDT, waste of time-money-effort.

Second step would be to coat the headers / exhaust manifolds. Again, a true thermal barrier coating rated at 2,000F or better. Now you're really containing the radiant heat beneath your engine.

Third would be the muffler, containing the heat and directing it out the tailpipe.

Yes, you could put heat sleeve over the oil supply pipe, but I wouldn't expect that to do much.

[sjf911]

Chris, are you talking about internal or external coatings?

[TurboKraft]

External, at a minimum.
A few companies will coat the components inside & out, and fewer will warranty the coatings on the interior.

It is critical that the turbine housing's machined areas, those which mate against the CHRA and exhaust, are both masked off. While the coating isn't very thick, the CHRA mounting surface needs to remain as-machined.

[guru944]

T77911S:

Swaintech 3000 White Lightening pix :





Later..

[fredmeister]

Here is a heat shield I fabircated and mounted to the exhaust studs in the turbine housing. It wraps around the turbine housing scroll as much as feasible and takes advantage of the fact that air is a great barrier from heat transfer to the engine tin directly above the turbo.

There is not alot of space between the turine housing and the engine tin to work with to fit any sort of insulating material in place.

[guru944]

fredmeister:

This will work a lot better but cost ~ $ 50 on ebay... see Pics below.

HT60 GT40 HX52 Turbo Charger Steel Mesh Heat Shield Silver Blanket Wrap Springs | eBay

Next step is the Swain tech 3000 Ceramic Coating.......

Hope this was helpful.

[T77911S]

i was thinking of usuing some kind of blanket or cloth pad but figured the turbo would cook it.

i like freds idea and even wanted to do something like that but i did not want to undo any bolts plus i wanted some air flow over the turbo.
i wander why they dont put cooling fins on the exhaust side?

i am really thinking that wraping the oil lines in and out would be a major improvement.
the heat from the trubo has got to really heat up those lines and cook that oil.

[Uwon]

I quite frankly don't understand why there is so much hoopla about keeping the "heat in" in a turbo.
I have a 3.2 based motor converted into a 3.4 turbo with lots of goodies. I have run this motor for over ten years, approximately 250,000 km and have done about 10 DE days per year at Mosport, which high speed track when my car can reach 265 kph (165 mph) if all the moons line up coming out of corner 5b. In that time I have rebuilt the turbo once (early on) and freshened up the top end (mid way). The only evidence that I have had regarding "turbo heat" is a slight discoloration on the underside of the bumper and a little paint blistering on the engine tin immediately above the turbo (high heat paint was not used).
My theory is that you should let as much air move around as possible by the turbo rather than keeping the heat inside and trying to push it out the tail pipe. Doing the latter just raises the temperature of the turbo and keeps it in longer after shut-off promoting the boiling of the oil in the turbo bearings and then you are done.
T77911S has the right idea in his first pic. Protect the areas that you are concerned about with a shield (or high heat paint or other heat deflection material) and let air circulate.
My two cents worth.

[cole930]

I have a tendency to think we need to base what we do to control turbo heat
on how the car is used. Stock from the factory the 930 had little to nothing that
addressed the issue other than the heavy heat shield that was installed to
keep from burning the paint off your rear bumper.

When I did the Sled I added a couple things I thought would possibly help
turbo heat issues and protect the fiberglass rear bumper. Have no idea if any
of it will make any difference or not but I've tried.

I have a 934 turbo exhaust setup with a zork. I felt the openness of this
configuration lent it's self well to getting heat moving away from the engine
and out the back. I also sleeved the oil return lines to the scavenge pump with
1500 degree heat sleeve and added a heavy heat mat to the inside of the
rear bumper. I also bolted a small metal heat shield to the top header turbo
flange bolt holes that wraps over the top of the turbo.

Just throwing this out there as food for thought. I think, for a street car,
this will be as good as I can get without going way overboard for no gain
and added dollars.








Cole

[Tilikum Turbo]

Originally Posted by Uwon

I quite frankly don't understand why there is so much hoopla about keeping the "heat in" in a turbo.
I have a 3.2 based motor converted into a 3.4 turbo with lots of goodies. I have run this motor for over ten years, approximately 250,000 km and have done about 10 DE days per year at Mosport, which high speed track when my car can reach 265 kph (165 mph) if all the moons line up coming out of corner 5b. In that time I have rebuilt the turbo once (early on) and freshened up the top end (mid way). The only evidence that I have had regarding "turbo heat" is a slight discoloration on the underside of the bumper and a little paint blistering on the engine tin immediately above the turbo (high heat paint was not used).
My theory is that you should let as much air move around as possible by the turbo rather than keeping the heat inside and trying to push it out the tail pipe. Doing the latter just raises the temperature of the turbo and keeps it in longer after shut-off promoting the boiling of the oil in the turbo bearings and then you are done.
T77911S has the right idea in his first pic. Protect the areas that you are concerned about with a shield (or high heat paint or other heat deflection material) and let air circulate.
My two cents worth.

There's a balance between the inlet temperature(air intake) and outlet temp of the exhaust. The farther you push these two away from each other(delta-T), the greater the power and efficiency(and when your engine is not running, no Delta-T, no efficiency, system is dead). So you want it hot...just not too hot.

The old drag racers of yore...thought it was a good idea to keep the hood off the car and keep the engine cool....except they didn't know it forced the engine to run rich(which is not the desired result because the engine does not make it to a proper operating temperature) which eventually will send the engine to an early rebuild or grave.

[T77911S]

Originally Posted by Uwon

I quite frankly don't understand why there is so much hoopla about keeping the "heat in" in a turbo.
I have a 3.2 based motor converted into a 3.4 turbo with lots of goodies. I have run this motor for over ten years, approximately 250,000 km and have done about 10 DE days per year at Mosport, which high speed track when my car can reach 265 kph (165 mph) if all the moons line up coming out of corner 5b. In that time I have rebuilt the turbo once (early on) and freshened up the top end (mid way). The only evidence that I have had regarding "turbo heat" is a slight discoloration on the underside of the bumper and a little paint blistering on the engine tin immediately above the turbo (high heat paint was not used).
My theory is that you should let as much air move around as possible by the turbo rather than keeping the heat inside and trying to push it out the tail pipe. Doing the latter just raises the temperature of the turbo and keeps it in longer after shut-off promoting the boiling of the oil in the turbo bearings and then you are done.
T77911S has the right idea in his first pic. Protect the areas that you are concerned about with a shield (or high heat paint or other heat deflection material) and let air circulate.
My two cents worth.

that was a big consideration for me. keep the heat in or wrap the turbo to keep the heat from radiating out. i dont understand this concept yet, ot only for the turbo for the exhaust systems and wrapping them. would wrapping the exhaust pipes at the heads reduce head temps?
still the big thing is keeping the things around the turbo cool. the dizzy gets so hot you cant touch it.
i feel like the best gains from any of this would be protecting the OIL lines that run to and from the turbo. with the heat from the turbo heating up the oil supply line that is reducing any cooling the oil may provide.

[sjf911]

What effect does wrapping the turbine housing have on post shutdown bearing temps and coking risk especially with a water cooled unit left open to air?

[Tippy]

Try to balance these things and it gets complicated:

1. Higher the heat retained on the turbine side, quicker the spool.
2. Higher the heat retained in the turbine side reduces life
3. Slower you allow the heat to dissipate is better for the metals inside the turbine (faster is worse from what engineers have told me over and over again)
4. Slower you allow the heat to dissipate raises chances of coking.

Guess you can't have it all!!!

[fredmeister]

The air serves as the best form of heat shield which is why placing a metal shield over the turbo with an air gap between it and the housing and an air gap between the shield and the engine compartment works so well.

The second reason for the heat shield is to prevent radiation heat from impinging on the engine sheet metal as it pours off the turbine housing. Painting it matte black lowers its emissivity for radiation heat.....which is why Porsche and VW used black paint on the engine tins.

I used some thermal heat wrap tape to prevent the heat shield I made from contacting the turbine housing but did not wrap the turbine housing completely with the stuff so it could still cool by convection. This should prevent cooking the center section like you would with a thermal blanket type wrap.

My dizzy still gets hot so nothing is gonna stop this from occuring but the degree of heat it sees should be substantially less than before the heat shield.

I track my turbo at PCA DE events and dont have a problem with paint discoloring on my bumper or engine compartment sheet metal. However, my plastic rear reflector is badly warped and water literally boils off the bumper above the turbo after a run if I pour water on it.....thats nuts.

Just to throw more suggestions out there, I wrapped my O2 sensor wires with thermal tube wrap to prevent it from frying as it ran above the muffler along the underside of the engine sheet metal. I noticed the insulation getting brittle near the sensor where it mounts to the muffler inlet.

Fred

[T77911S]

air flow was something else i was thinking of.

i was trying to come up with a way to put a little "air scoop" under the the turbo or the motor to divert some air up and around the the top of the turbo.