Jason in Texas - ext. track - 09 SS/TC

Desert Sasqwatch

Goblin Guru
News update Austin: state motor vehicle authorities have mandated that all specialty use and kit car vehicles who want to register in the state of Texas must meet strict new sound laws and are requiring the use of a new Flowmaster Mega Quite Muffler. Please make allowance for extra space necessary to mount this muffler to be in compliance with the law.
o_O;):cool:
 

G Atsma

Goblin Guru
News update Austin: state motor vehicle authorities have mandated that all specialty use and kit car vehicles who want to register in the state of Texas must meet strict new sound laws and are requiring the use of a new Flowmaster Mega Quite Muffler. Please make allowance for extra space necessary to mount this muffler to be in compliance with the law.
o_O;):cool:
A trailer may be advisable.....
 

JBINTX

Goblin Guru
It has been such a joy meeting other Goblin builders in the area. Today was no different. I drove across town to Scott's place (SACTX). A big thanks to him for helping me load a dyno'd tune to my ECU. BOOYAHH!!!! Big power now. And a big shout out to Indie Lonnie way up north for sharing the tune.
Scott has a precious wife and small kids who had only heard about what their daddy was going to build. So, watching his son's face after he took a ride with his dad in a race car that was the same that his dad was going to build - priceless..........

IMG_8512.jpg
 

SACTX

Well-Known Member
We had a great time also. It was my first opportunity to drive a Goblin and it is amazing. A couple of more pictures.

My Wife Gris was all thumbs up and smiles after her ride and Alan climbed back in the car and started buckling up for another ride. He had a blast and told me later on in the evening that he wanted to go for another ride in the race care.

Thank you for coming up!
 

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Ark :D

Goblin Guru
Your son looks like he's bracing himself for a launch, lol!

My wife is terrified of the Goblin and it doesn't even have wheels yet. I doubt I'll ever get her into mine. :(
 

JBINTX

Goblin Guru
Your son looks like he's bracing himself for a launch, lol!

My wife is terrified of the Goblin and it doesn't even have wheels yet. I doubt I'll ever get her into mine. :(
I want another report from you about 6 months after you are done.
By then, Jeremy be saying "Honey, can I have a turn on the Goblin, please?......." :p
 

Ark :D

Goblin Guru
Hah, I want to believe that'll happen, but ..... she views the Goblin as an oversized go-kart with way too much power compared to its weight. I'll be lucky if she allows my kid to get in it. In fact, if she had her way, I would just sell it immediately.

Hell, this weekend, she asked me if I had any buyers lined up yet. C'MON MAANNNNN
 

JBINTX

Goblin Guru
Hah, I want to believe that'll happen, but ..... she views the Goblin as an oversized go-kart with way too much power compared to its weight. I'll be lucky if she allows my kid to get in it. In fact, if she had her way, I would just sell it immediately.

Hell, this weekend, she asked me if I had any buyers lined up yet. C'MON MAANNNNN
Ohhhh MAN!
Don't let her read this, but she is kind of right with her description of the Goblin. But, we have four wheels. And a roll cage. And harnesses.
I am assuming there are no motorcycles for you in the near future.... :)
 

Ark :D

Goblin Guru
Yeah I know she's technically right. Thus far, I've been able to evade the questions by promising I'll wear a helmet while driving it.

I knew this was going to be an issue as far back as a year ago, when I saw the color drain out of her face upon hearing that the airbag wiring was getting stripped from the harness. She's no dummy.
 

Ross

Goblin Guru
Time to start talking about the crotch-rocket motorcycle you are going to get.
My Goblin is my wife's compromise, as I use to race my Yamaha R6, and 2 other dirt motorcycles.
The Goblin is "way safer" from her point of view.

My point of view:
These toys are only as dangerous as you make them.
A super-safe car can be deadly in the wrong hands, and a race motorcycle can be safe for 40 years of racing (knock on wood).
It is all up to the driver, and common sense.
 

Ark :D

Goblin Guru
Absolutely. I've told her a dozen times, I'm 41 years old and I already got all the stupid out of my system while I was younger, to the detriment of several Mustangs I used to own. But, she counters with "It's not you I am worried about". She knows other people drive like idiots, and doesn't trust them not to smash me into oblivion.

She'll be fine, once it's done and I've driven it without incident for a while.
 

Rttoys

Goblin Guru
Time to start talking about the crotch-rocket motorcycle you are going to get.
My Goblin is my wife's compromise, as I use to race my Yamaha R6, and 2 other dirt motorcycles.
The Goblin is "way safer" from her point of view.

My point of view:
These toys are only as dangerous as you make them.
A super-safe car can be deadly in the wrong hands, and a race motorcycle can be safe for 40 years of racing (knock on wood).
It is all up to the driver, and common sense.
Exactly. They are only as dangerous as you make them. You can’t control everything, but you can control most things.
 

Justin

Active Member
Where did you get those side scoops? Did you buy them or fabricate them? Any chance I can get a close up pic of one, I would really like to do the same thing on my car
 

JBINTX

Goblin Guru
Where did you get those side scoops? Did you buy them or fabricate them? Any chance I can get a close up pic of one, I would really like to do the same thing on my car
You are the first one to notice them (or at least ask!).
I will give some background with the requested info. And a long answer ;)

I started data logging some ambient / IAT / coolant temps to see where I was. Houston daytime temps are getting to low-90’s now. I laid out an eight mile route where I could intermittently stop and record data. My turbo setup is all stock and assembled with all DF parts for the intake system. Like others, I found I was consistently getting 12-15 degrees higher temps for IAT over ambient. I found a few ideas on the forum here:

http://dfkitcar.com/forum/index.php?threads/things-to-do-while-quarantined.1663/

There is plenty of other stuff out there regarding cold air intakes. It is one of those ideas that you just inherently know is a good for power (cold air is more dense than hot air). The true impact is a little tough to quantify without dyno testing before and after modifications. My garage dyno seemed to be missing from the tool box….. That did not stop me.

My first thought was to not route the intake to the cold air, but rather route the cold air to the intake. I fabricated some scoops for the side of the engine bay. I thought the look of the scoops was cool. I made them from 0.160" aluminum. Overkill on thickness. They could probably be 0.08". Just Adel clamped to the frame. After installing the scoops, I returned to my data logging driving. Temps were reduced to only 7-9 degrees above ambient. Not bad! The scoops were definitely forcing in air to the front side of the engine bay. But, I immediately felt the impact of the scoops with more heated engine air rolling forward into the cockpit on the back of my neck. Not a good unintended consequence. Less than ideal. I also understand that controlling the air flow in and around the engine bay is not simple. I took an idea from Porsche. On the Boxster, they have a small “windscreen” between the two headrests to stop the back flow of air. I cut some Plexiglas and made a small temporary shield between the seats. It reduced the heated air into the cockpit somewhat. Not sure I will keep it there, though.


61582913443__A2749B44-DA51-4BA5-82FE-8E65219A8FF9.JPGIMG_8313.jpgIMG_8316.jpgIMG_8375.jpgIMG_8376.jpgIMG_8377.jpgIMG_8378.jpgIMG_8379.jpgIMG_8476.jpg


And yes, I am a degreed engineer with AutoCAD skills. Sometimes cardboard is just too simple, quick, and dirty... ;) An old engineer once told me the only difference between an engineer and any ol' redneck is time and money. :) I got some redneck in me too......

I then went back to Indie Lonnie and Lethalcast (link above) and their solution. Part of me knows that shorter distances for air to travel are probably better - at least within the requirements of the MAF sensor. The aluminum pipe running around the engine bay carrying relatively “cold” air is not ideal with aluminum being such a great conductor of heat. I want to point out that Lethalcast did attempt to mitigate the heat by thermal wrapping the long tube that ran across the engine bay. Rather than running the intake across the engine bay to the driver side, I will simply turn it out. At one point, I looked into an Arial Atom / F1 snorkel setup. I read an article that an F1 going 230 mph only gets about a 2% increase in HP due to the added pressure from the speed of the air getting “rammed into” the duct. I would have thought it would be a little more. The article did not address the “cold” air versus hotter engine air HP increase. Again, it is a given that taking in “colder” air is the right direction for engine performance. Jeep snorkels look cool (on jeeps), but they are there more to not suck water in fording through rivers. I really did not want to snorkel up the Goblin. However, you cannot get away from sticking something into the cold air stream to collect it. I figure the coldest intake air is if the intake is outside of the engine bay in a stream of cold air. So, I figured why not give this a try to see what the IAT would get down to. Not done with that yet, so more to come.

There are some other variables here as well. The intake air has to travel through the tubes which are in close proximity to the engine and will therefor heat up. The air to water intercooler is not infinite (or instant) in cooling capacity and has limitations as to how much heat it can take out of the intake air stream. So, it is probably not really possible for us to get the IAT all the way down to ambient. This brings up another idea of either insulation wrap, or heat shields for post intake tubing. I will try that as well. As for engine heat mitigation, there are plenty of other points to address it as well. I may upgrade my radiator fan like Russel (Rttoys) to a higher power Spal model. I am also contemplating a remote oil coiler as well. That would fit in the driver side scoop well. I welcome others advice on their list of projects they are / would like to do and in what order of importance.

On a side note, I was curious as to what speed of the air flows into the engine. After some calculations assuming 2.0 Liter engine, 4 stroke cycle, zero boost, 5,000 rpm, 3” diameter intake duct, I got this: the intake air flows at 91 in/s = 7.6 ft/s = 5.2 mph. Part of me was surprised at the volume and the speed that it flows. 14;1 air to fuel means lots of air, obviously. The good news is that fluid dynamics says that at that speed, not a lot of bad things come into play such as flow restrictions due to elbows and internal friction (even though it is good to avoid bends and restriction when possible). Given all that - at the end of the day, getting the coldest, densest air to the cylinder is the elusive quest.

So, the question was about scoops, right?..... :)
 
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Justin

Active Member
Awesome thanks for all the great information. I mounted my intercooler heat exchanger in the engine bay right behind the driver seat and these scoops are exactly what I need to feed some cold air to the heat exchanger. How are you logging your iat1 and iat2? I have the torque app but cant figure out how to see my iat2.
 
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