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Potential mod idea to decrease IAT. Want oppinions.
In a few months Ill be completely overhauling my car and really want more hp to boot. I've decided to go with a BNR turbo for ease of install but also because im wanting to keep the stock TMIC. There are a few reasons for this:
1: a V mount is way outside my price range.
2: adding a FMIC to the front require you to cut up the car and I'm not a fan of that either
3: a FMIC would restrict airflow to my already struggling AC and living in Florida id rather keep my AC than make power gains if it comes to it.
4: I bought a CF hood for my car (was a GXL) and swapping the IC to a FM would just feel a kick in the pants for me.
So I've been thinking about ways to fix the shortcomings of the stock TMIC. Those being the extremely hot IAT when running more boost (im wanting about 13 or so) and really shitty airflow out the cool side.
I've seen the post where someone put Heat resistant tape on the heat shield and it brought down the air temps, (TMIC Heat Shield Mod - RX7Club.com - Mazda RX7 Forum) and I also saw how someone modified the side tanks to increase air flow (if someone has the specifics on how he did that i would LOVE to hear!) (Stock top mount, beefed up... (*************.com))
MY IDEA:
I do have my own idea but I'd like to get your opinion's about it before I make myself look like an *** and do it on my own car without testing the water first. Basically I had the idea of adding aluminum sheets to the air pipes that run between the tanks. they'll be maybe 1 inch tall, just enough to reach the top of the ram air scoop above the intercooler. I thought by doing this it would increase surface area and give air direct contact with the metal without having to make that turn downwards into the intercooler.
Just an idea I thought I'd throw out and get some opinions. I'm not wanting to drag race my car. its a daily/autox(eventually)/freeway cruiser (i have a friend with a s14 I run with going to events and I want to keep up)
One more thing, there have been people who have assured me that for what im doing the TMIC would be fine but you can never be too careful
Basically I had the idea of adding aluminum sheets to the air pipes that run between the tanks. they'll be maybe 1 inch tall, just enough to reach the top of the ram air scoop above the intercooler. I thought by doing this it would increase surface area and give air direct contact with the metal without having to make that turn downwards into the intercooler.
The stock TII hood has a rubber / foam gasket that runs around the hood scoop along the bottom. When you close the hood this forms a seal with the intercooler so air doesn't leak out and around the core.
Is this seal not present on your hood? If not, that's the first and easiest gain to be had. It sounds like what you're describing would perform the function of the seal unless I'm misunderstanding. At the end of the day though, more metal on the intercooler is better since there's more mass into which you can sink heat. Unless you're welding these tabs on though I don't think they'll end up transferring a meaningful amount of heat.
It's also worth noting that there were aftermarket TMICs available, although finding one now may be tough. Or if you're good at welding aluminum buy a core and make custom end tanks and mounting points.
Another option is water / methanol injection. It isn't cheap to get the kit but it's space efficient and buys you some margin with regards to boost without requiring you to cut the car for a FMIC or change your hood for a v-mount.
The stock TII hood has a rubber / foam gasket that runs around the hood scoop along the bottom. When you close the hood this forms a seal with the intercooler so air doesn't leak out and around the core.
Is this seal not present on your hood? If not, that's the first and easiest gain to be had. It sounds like what you're describing would perform the function of the seal unless I'm misunderstanding. At the end of the day though, more metal on the intercooler is better since there's more mass into which you can sink heat. Unless you're welding these tabs on though I don't think they'll end up transferring a meaningful amount of heat.
It's also worth noting that there were aftermarket TMICs available, although finding one now may be tough. Or if you're good at welding aluminum buy a core and make custom end tanks and mounting points.
Another option is water / methanol injection. It isn't cheap to get the kit but it's space efficient and buys you some margin with regards to boost without requiring you to cut the car for a FMIC or change your hood for a v-mount.
Forgive the crappy sketch but this is essentially what I want to do. Also no, my CF hood never came with the rubber lining for the IC and while ive been looking arround for one no one has been able to get me one without buying the whole hood and I'm not ok with that, however I could take that route as well and make a back plate to force air downward using the added fins as supports.
I have thought about meth injection and I think Ill go that route once I've run out of options. Im in college and they let me use their welding facilities so doing this isn't that expensive for me.
Oh I see, so you're hoping to try and use the fins themselves to dissipate more heat. Well like I said it should "help" in the sense that extra mass will be better at dissipating heat, but it might not be a meaningful amount. Are you intending to weld them in? Otherwise I can't imagine a lot of heat transferring into the fins by any other mounting method.
I think the missing seal is going to be most of the issue. You could try Mazda and see if they still sell it. Or make your own out of generic weatherstripping or something, even as a temporary solution.
EDIT: Sorry, just re read the comment and saw the bit about the welding. This mod can't hurt as far as I can tell (as long as you don't blow any holes in the IC core while welding of course), so why not? You can always buy another stock IC if it doesn't work out.
Oh I see, so you're hoping to try and use the fins themselves to dissipate more heat. Well like I said it should "help" in the sense that extra mass will be better at dissipating heat, but it might not be a meaningful amount. Are you intending to weld them in? Otherwise I can't imagine a lot of heat transferring into the fins by any other mounting method.
I think the missing seal is going to be most of the issue. You could try Mazda and see if they still sell it. Or make your own out of generic weatherstripping or something, even as a temporary solution.
EDIT: Sorry, just re read the comment and saw the bit about the welding. This mod can't hurt as far as I can tell (as long as you don't blow any holes in the IC core while welding of course), so why not? You can always buy another stock IC if it doesn't work out.
thats the other thing! Ive been running an s4 intercooler on an s5 upper intake manifold and its kind of driving me nuts (my s4 lower intake manifold decided to break into pieces). Im picking up a proper s5 intercooler tomorrow so Ill just use the old IC as a test subject. You do have a point, ill see what I can find to maybe transfer more heat into the added fins cuz that is an issue.
Now that I see the sketch of your idea, I get what you're trying to do. Don't know if it will improve anything, as I think there's probably good reasons why the IC wasn't designed that way from the get go. On one hand, it will increase surface area, which is typically a good way to improve an IC's efficiency. But on the other hand, those fins sticking up like that will increase aerodynamic drag, so you may end up reducing the volume/flow of cool air from the scoop and through the IC core, which could have the net effect of reducing the IC's cooling efficiency.
I think the best bang for the buck improvement you can do here is:
- Get an S5 TMIC in there.
- Fabricate a simple weather strip seal between your aftermarket hood & the perimeter of the S5 IC. Shouldn't be too hard to find some medium density foam insulation strips that you can stick onto the perimeter of the IC; Size them so that when you close the hood on it, it just compresses enough to close off the gap between IC & hood to create the seal.
If you're still not happy with IAT's after that, a water/meth kit isn't too difficult or expensive to add in later.
1. The seal around the hood scoop is going to be your largest gain by far. Think about how your radiator needs a fan shroud/ ducting to pull air through the radiator core. If you don't have those, air short circuits and doesn't get used for cooling. It doesn't raise the performance of the IC, but it ensures peak cooling efficiency.
2. There is, and should be an aluminum sheet under the IC to shield it from radiant engine heat. Aluminum is a good material for this, but now that we have access to carbon tech, remaking that in a carbon layer could gain you more insulation from a hot ending. Might be neat to try.
3. Unless you put webbing between those extra fins on top, its not going to gain you much cooling with fast fluid flow. They're also not in the main path of IC air, so you will have diminishing returns the taller you make them. You could try to upgrade to a denser core to improve cooling, and remake the stock end tanks to fit that. Thats going to be on my list to try eventually.
With the power range we're working with, it's not really gainful to do stuff like refrigerate the IC like Dodge is doing, as there isn't enough expendable hp to run the pump. Water spray would help some if you want to keep filling it up.
I just had a thought, I wonder if anyone has ever repurposed the old cold starting fluid systems for a mild injection setup. Could be fun to experiment with...
seal the IC to the hood, like the radiator, get as much air as you can through that thing.
2, insulate it from the engine heat
that should help right there, also
find a colder air intake, the colder the air going in, the colder the air going out....
also the larger turbo could/should be more efficient, so for a given boost level, temps out of the thing should be the same of lower than the stock turbo
1. The seal around the hood scoop is going to be your largest gain by far. Think about how your radiator needs a fan shroud/ ducting to pull air through the radiator core. If you don't have those, air short circuits and doesn't get used for cooling. It doesn't raise the performance of the IC, but it ensures peak cooling efficiency.
2. There is, and should be an aluminum sheet under the IC to shield it from radiant engine heat. Aluminum is a good material for this, but now that we have access to carbon tech, remaking that in a carbon layer could gain you more insulation from a hot ending. Might be neat to try.
3. Unless you put webbing between those extra fins on top, its not going to gain you much cooling with fast fluid flow. They're also not in the main path of IC air, so you will have diminishing returns the taller you make them. You could try to upgrade to a denser core to improve cooling, and remake the stock end tanks to fit that. Thats going to be on my list to try eventually.
With the power range we're working with, it's not really gainful to do stuff like refrigerate the IC like Dodge is doing, as there isn't enough expendable hp to run the pump. Water spray would help some if you want to keep filling it up.
I just had a thought, I wonder if anyone has ever repurposed the old cold starting fluid systems for a mild injection setup. Could be fun to experiment with...
My $.02
Funny thing, I have the old cold starting fluid system still. Its disconnected but I did think of that so I might try to see what I can do. your talking about meth injection? I get the concept of meth injection but dont quite have an idea on how its properly set up or used (in depth stuff) so if anyone has any sources I can get to that information, that would be helpful.
as far as my hp goals, just enough to keep up with my buddy. his 240 is running about 250hp with a transmission geared for highway pulls, so I was thinking about 300 should do the trick though.
also, I finally found a OEM rubber hood seal so ill be using that now!
seal the IC to the hood, like the radiator, get as much air as you can through that thing.
2, insulate it from the engine heat
that should help right there, also
find a colder air intake, the colder the air going in, the colder the air going out....
also the larger turbo could/should be more efficient, so for a given boost level, temps out of the thing should be the same of lower than the stock turbo
What do you think about a turbo blanket? would something like that fit on a BNR turbo with it tucked into the engine?
also I want to make a cold air box but am not too comfortable with with that just yet so if you have any good references on how to do that, that would help. The tutorials I found are either on a completely different vehicle or extremely vague.
edit: I found a video from Gingium when he had his FC (RIP) that helped me out with the cold air box so Ill give that a shot when school opens back up and I can use the fab shop
If your original heat shielding is gone, you're definitely going to want a turbo blanket. I ran without one for a few years and I kept having to replace dried and cracked vacuum lines.
Here is the model I ended up getting, as well as how it fits on my engine.
If your original heat shielding is gone, you're definitely going to want a turbo blanket. I ran without one for a few years and I kept having to replace dried and cracked vacuum lines.
Here is the model I ended up getting, as well as how it fits on my engine.
THANK YOU! that helps a lot! no modification needed? Fortunetly for me there issnt much on that side of the engine bay anymore so any hoses that would be changed aren't there anymore.
On a different note, I just picked up my s5 intercooler and I noticed something that I didn't before. that being the inlet pipe being about .5 in larger than the S4 IC and the overall shape having very subtle changes. I've looked around and haven't found any information but are there any significant performance differences between the s4 and s5 intercoolers?
If your original heat shielding is gone, you're definitely going to want a turbo blanket. I ran without one for a few years and I kept having to replace dried and cracked vacuum lines.
Here is the model I ended up getting, as well as how it fits on my engine.
The OP's idea will help slightly if you were on the dyno and holding a high load/boost for a while, but otherwise won't have much of an effect. As the boost pressure and temperature rises and falls, it'll take time for the heat to make its way up those fins to get dissipated by the airflow. They'll add a little thermal mass to the IC, so that'll help a little bit for transient use but because they're long and thin, the IC body will heat up faster than the fins and the effect will be limited.
As others are saying, increasing the airflow through the IC by sealing the gap to the hood scoop, reducing the ambient underhood temperatures with turbo blankets or other insulation, a real cold-air intake to reduce turbo-inlet temperatures, and insulating the IC from conductive heat transfer from the engine block will all make more of a difference
06-27-21, 06:45 PM
