patsmx5

iTrader: (16)

We got to talking in another thread about this. Six believes that running a super hot exhaust system right by the transmission without a heat shield contributes to making them shift like crap. And I agree, it makes perfect sense. His post from other thread:

Potential benefits of shielding the exhaust:
1. Better shifting trasnmission
2. Longer transmission fluid life
3. Transmission life increased from not getting beat to death from heat AND power.


So, who has managed to shield their 3" exhaust from the transmission? I want to build a metal shield for mine, but packing looks really tight around the bell housing, and the rest too.

Girz0r

iTrader: (1)

Interested in this... Since it affects most of us

My first 'guess' without looking at my car would be to create a clam shell over the downpipe.

Here are some examples.

I wouldn't do this, but I'm sure it works for heat going in that direction.


Shell style, kinda like what goes over a catalytic converter. (#8)

Itty

Could you not use header wrap to insulate/shield the parts that are important to you?

ryansmoneypit

iTrader: (6)

Header wrap down low, sounds like a fire waiting to happen. Oil and whatnot, with a nice wick.

patsmx5

iTrader: (16)

I did this already, though I'm going to shield it too. The wrap doesn't help as much as I'd like.

Itty

Well based on the baller heat shield you made for your header, it seems like you are a fine candidate for pioneering something for shielding the transmission.

I'm thinking something bolted on to the bellhousing would work well. If you're mostly concerned with hot transmission fluid, then the most important place to shield wouldn't be the low clearance area around the bellhousing.

Even something like a polished stainless half-cylinder shape to go around the header wrap would do a lot for shielding and should add minimal thickness.

patsmx5

iTrader: (16)

Thanks! That header shield turned out fairly nice when it was done given how much I hate sheet metal.


Here are some pics of the area we are discussing on my car. I have a catalytic converter there too, so it makes clearance a bit worse vs a 3" pipe only.

greeenteeee

I thought this was thread was going to be about shielding the tunnel from the cabin before I clicked on it.

Anyway, I think something like what Girz mentioned may help. I'm surprised your header wrap isn't sufficient.

I am also reminded of what Adam/revlimiter did (for another issue but it can probably be applied here):
How to Eliminate Miata Gas Fumes (I hope?) ? revlimiter.net

sixshooter

iTrader: (12)

When I upgrade my transmission I will replace the hodgepodge of metal shields I am using with one nice piece I found. There's good shielding available in the junkyards that the OEMs paid nice money for already. Don't spend too much. Trucks and vans often have 2.5 and 3 inch exhaust pipes that required shields at some point in their length. And cars have nice dual layer shields attached to the body and fuel tanks. Some of them are quite large and can be sized to fit.

aidandj

iTrader: (5)

<p></p><p>Good idea. What 1 piece did you find?</p>

jpreston

iTrader: (4)

How did I manage to post this link in the DIY aero thread on the day that you guys made a heat shield thread?

https://www.pegasusautoracing.com/pr...paign=201509-1

This is the nicest aftermarket product I've seen for quick and easy exhaust shielding. It mimics the OEM heat shield design and doesn't create a fire hazard like exhaust wrap.

Itty

Kinda expensive though.. I like the junkyard option.

deezums

iTrader: (3)

I was about to post the same thing.

There's also dynamat sheethot, but it's spendy. It's a formable aluminum sheet, mini coopers have lots of this crap, some decent flat and round sections, for the junkyard guys.

Vibrant Performance SheetHot Heat Shields | Vibrant Performance

Look, wild miata in google images!

sixshooter

iTrader: (12)

My big double layer one piece came off the side of a plastic fuel tank on some vehicle that was being disassembled. I sell the big loaders with forks that junkyards use to move cars around so I get pretty good access to some of the yards. I don't know what the particular tank came off of because it had already been shucked from the chassis.

aidandj

iTrader: (5)

<p>I wonder if my stock heat shield is around. Might try and rig that up to the transmission.</p>

portabull

I think painting whatever shield you cobble up with a mixture of microspheres and paint would help isolate the heat. kind of like a homemade lizard skin.

sixshooter

iTrader: (12)

Overthinking this. ..

patsmx5

iTrader: (16)

You got it! I didn't make it from stainless because that stuff is really thick and hard to bend, and expensive, and I wasn't sure if these were even going to fit/work. So they're made from galvanized sheet metal for now.

This cost 10 dollars worth of clamps and sheet metal. Maybe.

Itty

Nice. I'm all for cheap solutions. Should work pretty well with that big of an air gap too.

aidandj

iTrader: (5)

Looks good. That is what I wanted to do but ran out of time. I did this instead.

$35 to my door.