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areogel heat sheild between block and intake manifold ea82T


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so, as yet another thing ive been wanting to discus is a heat barrier under the intake manifold, seems like the availability of areogel is making this a realistic idea.  i have done this in a late 80's Chrysler lebaron turbo, and i wrapped the turbo and used thermal tape on the intake and had fantastic results.   and that was using just radiant heat shielding.

what im talking about now is putting an areogel mat on top of the block, and then lining the underside of the intake with reflective radiant heat tape.  know the coolant passes directly next to and under the manifold,  that would also be insulated from the intake. 

word is that a areogel type gasket is also a thing being developed so bolted together parts don't transfer heat to eachother,  its mostly for fuel tanks but i don't see why it couldn't be applied elsewhere.

below is an example, im trying to take it a few steps further.

140080-BHCF.jpg?itok=ga7XlUGC

Edited by turbodog
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You will need a custom intake manifold if you want the coolant passage to be seperate to the air intake tract, the the manifold as such. 

On the EJ the coolant is separate to the intake manifold so keeping heat away from the intake is a whole lot easier. 

Keen to see where you go with this as a matter of interest more than anything. 

Cheers 

Bennie

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27 minutes ago, el_freddo said:

You will need a custom intake manifold if you want the coolant passage to be seperate to the air intake tract, the the manifold as such. 

On the EJ the coolant is separate to the intake manifold so keeping heat away from the intake is a whole lot easier. 

Keen to see where you go with this as a matter of interest more than anything. 

Cheers 

Bennie

yeah, i know its attatched,  but if i kept the majority of the intake cool, hopefully it only effects it a little,  where the majority of the heat is only coming in threw the coolant rather then the whole thing heat soaking.  maybe ill get lucky and the constant supply of incoming air will keep it cool!  im also bypassing the throttle body coolant.   radiators! radiators everywhere!  lmao

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The outside top of the EA82 would be slightly cooler than the coolant.  The hot coolant goes from the heads into the passage in the manifold.  The air flowing over the block & under the manifold would slightly help to cool it.   The manifold is not heated by the heat from the engine block being under it, it's heated by the coolant.

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3 hours ago, DaveT said:

The outside top of the EA82 would be slightly cooler than the coolant.  The hot coolant goes from the heads into the passage in the manifold.  The air flowing over the block & under the manifold would slightly help to cool it.   The manifold is not heated by the heat from the engine block being under it, it's heated by the coolant.

uhh are you sure about that?   heat doesn't just stop existing cause theres another form of heat nearby... like taking a blow torch to a frying pan while its on a stove top burner, saying only one of those is heating the pan

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That's quite different.  If the car is moving, air is blowing between the 2 parts.   The heat carried to the manifold by the coolant is far more than that that would be carried by the air drifting between them, even sitting still.  The coolant is at maybe 200 degrees.  The transfer through the air to another part that is heated by the 200 degree coolant is tiny, if any at all.

For the insulation to have a significant effect, you have to change the cooling system so the coolant doesn't flow through the manifold.

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5 hours ago, DaveT said:

That's quite different.  If the car is moving, air is blowing between the 2 parts.   The heat carried to the manifold by the coolant is far more than that that would be carried by the air drifting between them, even sitting still.  The coolant is at maybe 200 degrees.  The transfer through the air to another part that is heated by the 200 degree coolant is tiny, if any at all.

For the insulation to have a significant effect, you have to change the cooling system so the coolant doesn't flow through the manifold.

not much air gets moved under that manifold,  and ive been thinking of doing just that.  i wonder if it would be possible to block that passage and re route it new holes drilled and threaded with a fitting and hose. 

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2 hours ago, DaveT said:

The way I've seen a few done is with aluminum blocks machined to go between the manufold.and the head.  Routs the coolant to hoses, the intake port passes through. 

oh yaaaasss thats perfect!   i wonder if a 3d printed one could work

https://3dprinting.com/products/filament/hi-temp/ 

 

seems like its stable up to 160F and dosnt soften early like standard filliments... hmmm i think i found the solution if this works

Edited by turbodog
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I think your efforts would be better spent isolating heat from the exhaust system and getting a clean, cool supply of intake air to the engine's inlet.  The intake charge spends such a small amount of time flowing through the intake manifold that it really doesn't heat up that much, especially if it's already been compressed and heated by a turbocharger.

Not that this idea wont help, but I don't think you would notice any difference on a dyno, for example.  These engines aren't particularly efficient at turning fuel and oxygen into power, and the power levels are so low that we're talking 0-2 hp total for modifications at this level.

A bigger radiator, some sort of high-flow water pump, lots of heat shields/ducting and a big intercooler would be more influential on engine performance and longevity.

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34 minutes ago, carfreak85 said:

I think your efforts would be better spent isolating heat from the exhaust system and getting a clean, cool supply of intake air to the engine's inlet.  The intake charge spends such a small amount of time flowing through the intake manifold that it really doesn't heat up that much, especially if it's already been compressed and heated by a turbocharger.

Not that this idea wont help, but I don't think you would notice any difference on a dyno, for example.  These engines aren't particularly efficient at turning fuel and oxygen into power, and the power levels are so low that we're talking 0-2 hp total for modifications at this level.

A bigger radiator, some sort of high-flow water pump, lots of heat shields/ducting and a big intercooler would be more influential on engine performance and longevity.

basically i'm doing every small reliability upgrade i can do,  its about my 20th EA series car, im not necessarily looking for power, im just trying to do as much heat management as possible... back in the really early days i took alot of inspiration from this car,  heat is a huge issue with these early turbo chryslers, and this one could hit 200mph...   i tried doing this to one i built about 6 years ago and i can say it made more power then i've ever seen come out of one of those engines,  thing was an 1/8th mile beast!  ive been wanting to try this for years on a 88+ vane style subaru and i came across one,  so i'm gonna do it!
imsa_lebaron_5.jpg

Edited by turbodog
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What if you were to measure any power gains on a stone cold engine and continue through to operating temp?

Wouldn't that represent any possible gains?

A clever fellow down under found that with propane as the fuel, he could tune more power out of an engine that got an intake air temp of 82°C ! This in turn created the need for better approach to cooling, so he worked on case by case water pump tolerances, cavitation elimination and made an inline thermostat housing for the bottom radiator hose. This housing incorporated recirculating yet to go through radiator coolant, through engine block again!

He is a Victorian, last name Robinson ? I have read short magazine article on his work in the 80s. Also seen his thermostat housing fitted to a Leyland P76 V8 , though never talked to owner about what extent of tune it had.

My most recent net search on this fellow was his award winning design for efficiency and emissions of a buildings diesel power generation system

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2 hours ago, Step-a-toe said:

A clever fellow down under found that with propane as the fuel,

Here I was thinking you’re blowing your own trumpet Steptoe! 

Happy New Year old fella! 

@turbodog - you could look into the aviation spec RAM heads, see what they did in the coolant pipe department. Also look at their EA81 as this could have some ideas for you too. 

Cheers 

Bennie

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1 hour ago, DaveT said:

I don't think 160F plastic would do well.  Normal thermostat opening is 190 / 195 degrees F.   The coolant is likely going to be a bit higher under the highest load / power conditions.

 its 160 C  not F , so if its that hot the plastic would be far from the biggest concern :)

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I agree with Carfreak85. I see this kind of wasted effort all the time on my DynoJet and it never does anything measurable. Under power the airflow through the manifold is so fast that it doesn't have time to pickup any significant amount of heat.

It might allow slightly more ignition timing and a slightly leaner mixture at the start of a pull from a low airflow RPM - but as it climbs out the air would be moving so fast it wouldn't have time to pickup any heat. And in any case you would need a tuning solution that would allow adjustment of timing and fueling. Not likely to notice the 1 or 2 HP it would make through the midrange. It won't do anything at all at peak. 

GD

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3 hours ago, GeneralDisorder said:

I agree with Carfreak85. I see this kind of wasted effort all the time on my DynoJet and it never does anything measurable. Under power the airflow through the manifold is so fast that it doesn't have time to pickup any significant amount of heat.

It might allow slightly more ignition timing and a slightly leaner mixture at the start of a pull from a low airflow RPM - but as it climbs out the air would be moving so fast it wouldn't have time to pickup any heat. And in any case you would need a tuning solution that would allow adjustment of timing and fueling. Not likely to notice the 1 or 2 HP it would make through the midrange. It won't do anything at all at peak. 

GD

im not really looking for ppwer gains, im just trying to do every heat management trick i can... i know how fragile these engines are, so i figured the more under control the heat is, the longer the engine will last.   if i dont gain power thats fine with me, but if i gain any,  well... that's an unintentional side effect!   this is also going to have the full exhaust heatwrapped.

i did this on my last car...  

photo_2019-12-31_15-34-51.jpg?width=622&

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Waste of time, added weight, and will just get wet with water, oil, etc and smoke when it gets hot.

If anything the aluminum manifold is a heat sink for pulling heat out of the cylinder heads and radiating it elsewhere. The EA82 heads already have enough of a hard time rejecting heat with their dinky cooling systems and tendency toward cracking. 

By wrapping and insulating everything you are keeping the heat IN. Which is good for turbochargers, etc - but bad for just about everything else. 

I see people like you come through every so often. Think they are going to re-engineer the world and there's all this amazing room for improvement. It just isn't there. And to really stop wasting your time on stuff like this, you need to TEST - which I doubt you have the capability to do. Mostly you're just going to turn everything into a heavy, sticky mess by doing all this and accomplish absolutely nothing. 

If there was economy, free performance, or overall reliability to be had - the Subaru engineers would have done that. These cars (when you could get parts for them) would routinely go 250k-300k+ miles with proper maintenance. Exactly what aspect of "reliability" are you trying to improve? By the time these kinds of mileages are registered on the vehicle - the body, suspension, and interior are pretty much garbage. And usually they were scrapped because they weren't cost effective to repair based on their value at the time. Not entirely because their "reliability" was suffering. Reliability is directly related to availability of repair parts - it's a machine and it WILL break. That's an absolute guarantee. So if you really want to improve reliability - get a lathe and a mill and whip up some replacement oil pumps and sell them. 

Spend your time on things that matter. You are spinning your wheels and wasting your energy on pennies and nickles. You should be picking up the dollar bills that are laying all over the place. 

GD

Edited by GeneralDisorder
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I have done the opposite with all the time I have wasted tinkering with my EA82T ...exhaust is naked apart from rattly shield rotting away around the cat. I made heat shields for my right hand drive brake master and lines, also the firewall.

Just an electric fan to get heat out if the engine bay whenever at standstill should help.

I am of same ilk ...yet to appreciate EJ conversion. Not expect power gains, just reliability and pleasure to drive.

WHUMP !! GD just fell off his seat !! I agree with GD suggesting if want EJ buy cheap EJ powered from factory.

Same sort of lines, I like EA body, will stick with simpler EA engines

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yeah ill keep that in mind GD, though im still going to try something,  maybe you'll let me throw it on your dyno,  i got nothing but time to spend on this,  there is not going to be a single stone unturned on this engine,  im building it for high speed endurance, wot for hours at a time is a big possibility

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You can put it on the dyno - we run it nearly every day. Baseline runs are $120.

The EA82 is an evolutionary dead end. It's got the heads and manifold of a tractor and the cooling system won't handle hours of WOT and full boost. Not to mention you can't get enough parts to keep up with the failures you will experience should you attempt that. Rebuilds aren't even meaningfully possible since no one is setup to main line hone the blocks and you can't get an oil pump from anywhere. 

It's a really poor choice of platform for a vintage/retro build. It's a wasteland out there for parts. The engine was just barely adequate in the 80's in stock form - now it's flat out garbage with EJ22's making significantly more power without a turbo and doing so with better fuel economy. My 1990 Legacy loaner car has 336k on the original drivetrain. 

GD

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6 hours ago, GeneralDisorder said:

You can put it on the dyno - we run it nearly every day. Baseline runs are $120.

The EA82 is an evolutionary dead end. It's got the heads and manifold of a tractor and the cooling system won't handle hours of WOT and full boost. Not to mention you can't get enough parts to keep up with the failures you will experience should you attempt that. Rebuilds aren't even meaningfully possible since no one is setup to main line hone the blocks and you can't get an oil pump from anywhere. 

It's a really poor choice of platform for a vintage/retro build. It's a wasteland out there for parts. The engine was just barely adequate in the 80's in stock form - now it's flat out garbage with EJ22's making significantly more power without a turbo and doing so with better fuel economy. My 1990 Legacy loaner car has 336k on the original drivetrain. 

GD

yeah, im well aware of how bad this engine is,  kind of the reason i want to try all these things.   if you seen some of the other posts ive made, you would see im doing a whole lot of small mods that hopefully make it a tad more reliable....  ive had dozens of ea82 turbos,  most of the mods ive tried separately with decent (yet small) results..

and yeah i know all about ej swaps, im not a fan of them at all...  ive got plenty of ej cars in my fleet... if im going to swap anything into a gl, it would probably be a turbo honda k series on its side with a dry sump

and i think your not giving the ea82 enough credit,  ive already driven a few modded ea82t's across the country with my foot on the floor (redneck cruise control lol)  in stock form i would agree with you fully that its not able to do so. 

 

and i think id take you up on that dyno run when im done,  im really interested in whats gonna come out of this one

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