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-   -   Options: Lower intake shield (https://www.rx7club.com/single-turbo-rx-7s-23/options-lower-intake-shield-1077513/)

Willopap 01-20-15 11:25 PM

Options: Lower intake shield
 
Hey guys! Sorry if I am resurrecting an old topic. I was wondering what some of you guys are doing to protect you're lower intake manifold from the high heat of the turbo manifold and turbine housing.
I was thinking of coating my lower intake, turbo manifold, and turbine housing with ceramic, and a turbo blanket to top it off.
Do you think this should be sufficient?
Thanks guys! :)

tom94RX-7 01-21-15 11:13 AM

lots of options. I made a heat shield for the turbine housing out of a stainless steel pot, and made a lim heat shield from a piece of sheet metal and put some good Aero-lite heat reflective tape on the lim. You can Google search all this stuff too.

Vicoor 01-21-15 11:57 AM

1 Attachment(s)
I also made a heat shield for the hot side from a stainless steel pot, but I used the 12"x12" inconel heat shield from turbo source to shield the intake manifold.
The 12"x12" shield fits perfectly and provides excellent radiant heat protection.

Howard Coleman 01-21-15 12:44 PM

thermal conductivity

iron 80
aluminum 205
stainless steel 68
inconel 9.8
mica .71, yes that is right, point 71

buy yourself a piece of 1/8th inch thick mica from McMaster Carr

P/N 85165K81 around $60.

hang it off the studs on the UIM/LIM.

i used a propane torch (1300 F) for 2 minutes on one side of the mica and could comfortably touch within one and a half inches from the heat point on the other side.

i don't recommend you do that with anything on the list above:)

complete your setup w a PTP LAVA turbo blanket. the lava allows almost no heat penetration thus lowering your underhood temps and your IATs.

howard

ptrhahn 01-21-15 03:31 PM

I may try out that mica, if I can cook up something that doesn't look too much like a high school art project.

Turbo blanket sure would be convenient on the turbo side, but they always seem to be a disaster on track cars.

P

Willopap 01-21-15 10:09 PM

Wow thanks for all the feedback! Definetly some good suggestions worth looking into!
Are guys guys talking about literally taking a stainless steel cooking pot and cutting/ drilling it accordingly? Thats an awesome great idea, I'm surprised I haven't seen that more.
Im definetly going to entertain the idea of the pot and either the mica sheet, Stainless sheet or an inconel sheet (from turbo source) sheet attached to the lower to shield it.
What are you're guys opinion on wrapping the downpipe/ manifold? Do you think it has the same effect as a turbo blanket and will deteriorate over hard driving/ track abuse?
Thanks guys.

Willopap 01-21-15 10:11 PM


Originally Posted by howard coleman (Post 11858998)
thermal conductivity iron 80 aluminum 205 stainless steel 68 inconel 9.8 mica .71, yes that is right, point 71 buy yourself a piece of 1/8th inch thick mica from McMaster Carr P/N 85165K81 around $60. hang it off the studs on the UIM/LIM. i used a propane torch (1300 F) for 2 minutes on one side of the mica and could comfortably touch within one and a half inches from the heat point on the other side. i don't recommend you do that with anything on the list above:) complete your setup w a PTP LAVA turbo blanket. the lava allows almost no heat penetration thus lowering your underhood temps and your IATs. howard

Thanks for all the info! Have any pictures? Just want to see the mounting :)

Howard Coleman 01-22-15 12:38 PM

yes to wrapping your exhaust...

here's my engine compartment a/o Nov.

http://imagizer.imageshack.us/v2/xq90/540/9VXOAm.jpg

note the Mica and PTP Lava turbo blanket.

using the comparative thermal conductivity numbers:

Mica shield would conduct 95 times less heat than a stainless steel shield.

Mica shield would conduct 13.8 times less heat than an inconel shield.

howard

billyboy 01-22-15 02:17 PM

If you don't want to deal with McMaster-Carr's cross border antics, this group -

Pyrotek - Homepage

specialize in refractory insulation and sound deadening (at least here) and commonly used on racecars. A couple square metres of material was gratis, maybe you can try your luck too. Bonded and riveted to the backside of a shield, with air gap and forced air supply from the front of the car, never an issue. Personally wouldn't use a turbo beanie (or wrapped pipes for that matter - more shielding) and ceramic or reflective tape on the LIM is window dressing!

Howard Coleman 01-22-15 03:39 PM

i was negative re turbo blankets until i read this report by the U of Texas:

https://docs.google.com/file/d/0B1DK...dU0/edit?pli=1

i felt that while a cover lowers under hood temps, which is really important from an IAT aspect i was concerned about the turbo bearings.

read on...

justturbo2 01-22-15 11:04 PM

good stuff howard. thanks

Hybrid G 01-23-15 10:28 AM

really good stuff here.

Now to clarify I have a lava turbo blanket (not on car yet) does it matter if you have a journal bearing or ball bearing turbo?

I have heard it can cook the bearings.....any solid truth to that?

Howard Coleman 01-23-15 10:41 AM

"I have heard it can cook the bearings.....any solid truth to that?"

according to a well instrumented study by the U of Texas (Austin)

http://imagizer.imageshack.us/v2/xq90/909/1zQwmt.jpg

lots of additional data if you read the paper link in post 10

Vicoor 01-23-15 11:17 AM

I can't say I don't enjoy the heck out of reading real technical info like that, But, I'm not sure it tells the whole story about whether or not a turbo blanket can cause failure/reduce turbo life.

The readings are all steady state, where there is a continuous flow of oil through the housing. What about the conditions that are present in a hot soak? Elevating the housing temperature that much and insulating it so the heat can't dissipate has to have an effect of some sort. Also, what about an oil/air cooled center section. With no coolant in the housing to boil off and absorb heat,,,,?

Also, while the data shows clearly there is a performance advantage, all the temperature data in regards to the hot side of the turbo is all surface temps. It would be great to see the EGTs at all the various points with, and without the blanket.

I have to say I don't have any direct experience with this, but I think I have a pretty good understanding of how it works. I Just feel a little more information would be good to be able to better evaluate the risk/benefit of the turbo blanket.

billyboy 01-23-15 03:32 PM

Study doesn't appear to address longevity of the housing material, which appears to be the main trade-off, especially at rotary temps.

Maybe if WRC style ones were available and didn't inflate the turbo costs by several multiples - but I wouldn't hold my breath - after all, we're still persisting with dumb, bolted flange turbos after all these years.

jacobcartmill 01-23-15 09:20 PM

howard, that test for referenced was interesting, but that test was with a piston diesel engine. the EGTs aren't even in the same galaxy as turbo rotary gasoline EGTs.

i have read posts of people tracking their rotaries with turbine blankets and getting the turbine housing hot enough to sag and become oblong. and rice racing has a very good post on RCC about running usual EGTs and posting close-up pictures of his turbine housing after doing extensive testing, and it was very badly overheated and cracked/chipping throughout.

i'm a proponent of heat shields with an air gap --well, if you're putting the car through any kind of real abuse like a road course. otherwise, blankets will be great.

GoodfellaFD3S 01-23-15 10:26 PM

"The temperature increase of the turbine housing was found to be significant which caused the exhaust gas temperature at the turbine exit to about 5-7 degrees C."

Good reading and thanks for posting it Howard, but that quote above tells me they're not dealing with anything close to rotary EGTs.

junito1 01-25-15 02:26 PM

2 Attachment(s)
My attempt.

rx72c 01-25-15 05:22 PM

Has anybody been able to log a noticable difference in IAT temps or back to back power etc?


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