Rear Undertray Extractor Design Question
#21
Elite Member
Thread Starter
iTrader: (16)
Join Date: Aug 2007
Location: Houston, TX
Posts: 9,339
Total Cats: 519
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
Hmm, is that with a good intercooler? I haven't done an 11 second pull yet to know for sure, but a 8-9 second pull is easily 50-60 over ambient and climbing with the current setup at only 23 PSI, so with 30 it's going to be worse. I figure I'll be 80-90 over ambient for sure with the current IC just going from 0 to the top of 4th at 23 PSI, probably 90-100 with more boost.
#23
Elite Member
Thread Starter
iTrader: (16)
Join Date: Aug 2007
Location: Houston, TX
Posts: 9,339
Total Cats: 519
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
No I'm talking about drag racing, come on you know me! So say from a stop, with everything just idling, and I haul *** down the 1/4 mile. That's about the most I'm going to beat on it. I just made up 11 seconds but it would be something like that maybe 12.
I often run 1/8 mile but 1/4 mile will be tougher temps to deal with of course and I want it to handle that too. I was just looking at datalogs of 1-2-3-and grab 4th pulls I've done to get an idea of what air temps do, and that took 8-9 seconds.
I often run 1/8 mile but 1/4 mile will be tougher temps to deal with of course and I want it to handle that too. I was just looking at datalogs of 1-2-3-and grab 4th pulls I've done to get an idea of what air temps do, and that took 8-9 seconds.
#24
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
I'll have to dig up more later, but here's a log of my MSM on a mustang dyno a few months ago:
![](https://www.miataturbo.net/attachments/race-prep-75/143708-rear-undertray-extractor-design-question-iat.png?dateline=1436161821)
looks like it actually went down during the pull, and then hovered up after. it was about 80-85* in there, it went down to 95* during pull, then went up to 100*.
So...like 20 delta?
And this is with a insect sized snail huffing through straw sized piping, I was actually expecting it to blow molten lava
![](https://www.miataturbo.net/attachments/race-prep-75/143708-rear-undertray-extractor-design-question-iat.png?dateline=1436161821)
looks like it actually went down during the pull, and then hovered up after. it was about 80-85* in there, it went down to 95* during pull, then went up to 100*.
So...like 20 delta?
And this is with a insect sized snail huffing through straw sized piping, I was actually expecting it to blow molten lava
#25
Elite Member
iTrader: (1)
Join Date: Jun 2006
Location: Warrington/Birmingham
Posts: 2,642
Total Cats: 42
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
<p></p><p> </p><p>Your coolant temps are rock solid because you have the IC tucked up inside the nose and not blocking any airflow to it.</p><p>That's also why your IAT's are high. If you want lower IAT's, lower the IC into the airstream, and suck it up that the rad will now have to work much harder to cool the engine.</p>
Last edited by richyvrlimited; 07-06-2015 at 09:28 AM.
#27
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
I was playing the v-mount question off some engineers at PWR (now C&R radiators). Just to get their thoughts on the design. Right after i said "v mount" i got a eyes rolling to the back of the head and a "uuuuggghhhh" noise was groaned. As it turns out to get the maximum amount of efficiency out of a radiator you want the airflow to travel straight threw the fins. the idea is to Keep the air speed as high as you can. You don't want to force the air to take a 90* turn first.
__________________
OG Racing
Your Source For Motorsports Safety Equipment
WWW.OGRACING.COM
800.934.9112
703.430.3303
info@ogracing.com
OG Racing
Your Source For Motorsports Safety Equipment
WWW.OGRACING.COM
800.934.9112
703.430.3303
info@ogracing.com
#28
Elite Member
Thread Starter
iTrader: (16)
Join Date: Aug 2007
Location: Houston, TX
Posts: 9,339
Total Cats: 519
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
<p></p><p> </p><p>Your coolant temps are rock solid because you have the IC tucked up inside the nose and not blocking any airflow to it.</p><p>That's also why your IAT's are high. If you want lower IAT's, lower the IC into the airstream, and suck it up that the rad will now have to work much harder to cool the engine.</p>
I was playing the v-mount question off some engineers at PWR (now C&R radiators). Just to get their thoughts on the design. Right after i said "v mount" i got a eyes rolling to the back of the head and a "uuuuggghhhh" noise was groaned. As it turns out to get the maximum amount of efficiency out of a radiator you want the airflow to travel straight threw the fins. the idea is to Keep the air speed as high as you can. You don't want to force the air to take a 90* turn first.
See I've wondered about this. I've looked at the heat exchanger layout on A LOT of cars and pics online, and almost nobody does a v-mount type layout. Mercedes does the bottom mount exchanger for an oil cooler on my C63.
But OEMs don't use bar/plate IC's either, yet those are common in the aftermarket world too. I have seen high powered cars with the heat exchangers leaned at an angle though, there are several cars I've seen do that, even some OEMs (new viper does it about 30* off of vertical, corvettes do it). But it's more like 30* off not 90 as you are talking about.
#30
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
No I'm talking about drag racing, come on you know me! So say from a stop, with everything just idling, and I haul *** down the 1/4 mile. That's about the most I'm going to beat on it. I just made up 11 seconds but it would be something like that maybe 12.
I often run 1/8 mile but 1/4 mile will be tougher temps to deal with of course and I want it to handle that too. I was just looking at datalogs of 1-2-3-and grab 4th pulls I've done to get an idea of what air temps do, and that took 8-9 seconds.
I often run 1/8 mile but 1/4 mile will be tougher temps to deal with of course and I want it to handle that too. I was just looking at datalogs of 1-2-3-and grab 4th pulls I've done to get an idea of what air temps do, and that took 8-9 seconds.
pretty much any config should have no problem with it.
#31
Elite Member
Thread Starter
iTrader: (16)
Join Date: Aug 2007
Location: Houston, TX
Posts: 9,339
Total Cats: 519
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
Well not any config, cause the current one doesn't like it even at 23 PSI. And I don't think any config is going to take 30 PSI from a SC and have no problem to be honest. This isn't your wastegate pressure turbo kit on a stock engine.
Thread
Thread Starter
Forum
Replies
Last Post
bigmackloud
Miata parts for sale/trade
19
01-08-2021 11:24 AM
stoves
Suspension, Brakes, Drivetrain
5
04-21-2016 03:00 PM