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V1 Josh's City Goblin - 10 XFE Donor

jirwin
Wrapped the intake and charge pipe in reflectagold to see if it would help IATs. Seems to have made a difference, although I don't have hard numbers to back that up. I will say that after a drive around in traffic I was still able to touch the pipe that's above the turbo by hand. Previously it was too hot.

54181
 
Desert Sasqwatch
Keep in mind the thermal barrier works in both directions. Your hand may not get touching the outside of the pipe as it did before, but this barrier is also keeping the heat inside the pipe too. This may be a contributing factor to a higher (but probably very minor) increase in air temp inside the pipe, where the bare pipe could disapate some the heat with no wrap.

The thermal wrap on the cold air pipe between the air box and the turbo inlet is a better idea, especially with this pipe routed over the exhaust header and turbo.
 
jirwin
Gtstorey said:
Everything I've seen on the "foil" tape is that it has no real insulation value. Which isn't really surprising if you think how thin it is.
Click to expand...
Desert Sasqwatch said:
Keep in mind the thermal barrier works in both directions. Your hand may not get touching the outside of the pipe as it did before, but this barrier is also keeping the heat inside the pipe too. This may be a contributing factor to a higher (but probably very minor) increase in air temp inside the pipe, where the bare pipe could disapate some the heat with no wrap.
Click to expand...

This isn't thermal wrap like header wrap. It theoretically reflects radiant heat. It's not supposed to hold anything in or have any sort of insulating effect like header wrap or similar would.

Desert Sasqwatch said:
The thermal wrap on the cold air pipe between the air box and the turbo inlet is a better idea, especially with this pipe routed over the exhaust header and turbo.
Click to expand...

Yeah, I'm not sure if I like my solution here or ZZPs better. Obviously longer intake like I have is worse for flow, but ZZP's solution included in the kit just puts the air filter straight above the header/turbo. I read about some people here not liking that, so I decided to try routing it to the "airbox" I had made for the supercharger setup. It seems to work fine, and my IAT2s are lower than with the supercharger. I (effectively) don't have IAT1 since my ECU doesn't support both (routed what would be IAT2 to IAT1 sensor) so I don't know if it's better or not. I feel like my solution probably heat soaks more, but I like the packaging better. I'm fairly confident it helped quite a bit having the filter covered on 5 of 6 sides for the rain during Sick Week
 
Rauq
DS went down this rabbit hole with heat sink tubing. My napkin-math found that the airflow for decent power is doing like 100 ft/s through 2.5" tubing, so you're in contact with the entire run for no more than a half second. Molecular level thermodynamics aren't going to change that there's only a degree or two to be gained or lost by insulating or cooling your piping. Insulating might make a difference in an enclosed engine bay where the piping is being cooked by radiation and convection of stagnant air, but I doubt it's doing much on the back of a Goblin. If you look hard enough you can find a picture of my tongue on the heater core bypass hose on my Goblin after beating on it on the street, following a hypothesis by others that the exhaust was dumping heat into the cooling system by radiation.

So my armchair analysis is that it's probably not helping or hurting much either way, but I would definitely agree it looks cool.
 
jirwin
Desert Sasqwatch said:
Then please explain how the bare aluminum charge pipe coming from the turbo could not be touched versus how it can be now that the foil wrap is installed? Be specific.
View attachment 54182
Click to expand...

Not the charge pipe, but the intake tube above the turbo, pre-turbo. Its not scientific, it just felt cooler. After I do some longer drives in traffic we'll see how hot it really gets. All I'm saying is that it previously got too hot to touch. Now, so far, it doesn't. As @Rauq stated, it probably doesn't matter anyway, but oh well. Can't hurt really
 
G
I guess it might help some on sunny days.

I know I said insulation, but I really meant that the tests I've seen indicate it doesn't do much, especially in the temperature ranges we deal with.
 
Desert Sasqwatch
There are lots of factors at play when trying to determine how quickly heat can be transferred in a medium. No doubt the short runs of charge pipe tubing used in a Goblin have very rapid airflow at 100 fps - 0.5 sec is probably spot on. But how fast is air thermal conductivity? In dry air it is 1520 fps, so a thermal source out paces the speed of the airflow by factors. How about radiant heat? It's even faster at 984 million (yes million) fps - almost regardless in a gas medium. But what prevents the transfer of this heat is the thermal mass of the air molecules. It takes a lot of conductive heat to travel any significant distance, but the temperature gradiant from one point in space to another also determines how rapidly an equilibrium can be reached in an enclosed volume of air - like in a charge pipe. The transfer of thermal energy of the volume of air in a charge pipe does not need to be in direct contact with the metal to transfer heat into it and the radiant heat coming off the metal pipe is emitted much faster. So stating that no heat reduction occurs in the air flow within a pipe through radiant heat from the exterior is incorrect. Granted the thermal properties of the aluminum pipe, the internal temperature and the ambient temperature outside the pipe are also factors that determine this action. But the short story is that thermal dynamics will allow an aluminum charge pipe to radiate (or absorb) heat - conductive and radiant - in the Goblin plumbing. Adding a reflective layer to the exterior, for radiant heat protection helps keeps this outside - or keeps some radiant heat inside the pipe from escaping through the pipe to the exterior. My original explanation is not incorrect and the rabbit hole is not just a fantasy.
200w.gif
 
jirwin

Woo! This must have been what Bo was hinting at when I stopped by to get the turbo sorted earlier this year! Should help my 60ft a lot!
 
jirwin
Well... I'm confused on my springs. I was poking around here a long time ago and I had this post by @Ross bookmarked:
dfkitcar.com

V1 - Front wheels shaking and hopping under hard braking (Now fixed!)

Justin Reed & George (that is his forum name) but he goes by Brad, both are hard core racers, and run 600 lb/in springs up front. Brad has QA shocks, but a bit longer than the DF supplied ones.
dfkitcar.com dfkitcar.com
I ended up buying those 225/475 progressive springs because the roads in Bay City are so so so bad. Driving a normal car is awful, let alone the Goblin. So, I though that the progressive would be the ticket! Admittedly since I bookmarked these forever ago I did very little research when purchasing these recently. When I went to put them on just now I noticed that the new ones were way longer. High travel, makes sense. They do look like they would still fit, I would just have to adjust them down a bit. So... I started reading again on here and now I'm more confused than when I started.

I saw this post:
dfkitcar.com

V1 - Front wheels shaking and hopping under hard braking (Now fixed!)

Justin Reed & George (that is his forum name) but he goes by Brad, both are hard core racers, and run 600 lb/in springs up front. Brad has QA shocks, but a bit longer than the DF supplied ones.
dfkitcar.com dfkitcar.com
I took a look around the car and I have 300s up front right now, and 400s in the rear. This makes sense because I bought the coilovers a few years after finishing the build.

So in summary, if I'm understanding things correctly, I want the 300s that were formerly in the front on the rear and the new 225/475s on the front? Does that sound right?
 
G
I would start with just swapping the 300/400. I was very much surprised at how well the Goblin rides, although I pick my drives to be good pavement for the most part.
 
Rttoys
“Stock” is 400F/300R

I too have the 225/475 up front and love them for street driving. It really smoothed out the car a good bit. You will technically need the 1” longer shock though. You can squeeze them on the stock shocks, but it’s sketchy and leaves you no room to loosen them up any.
 
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