Aerodynamics

[Waterdriver]

I kind'a got a scan today? Lol

 

[Ross]

Ok so I found this: View attachment 36034

Adam put it up on this thread in 2015. Do you think DF would ever release this 3d model to the comunnity?

I didn't see Adam today, but asked @Lonny about this. He said that this model isn't all that accurate, but thought it could be posted out here for us to use as a modelling tool.

 

[Davidljones88]

Do you have a link to buy front wing mounts?

 

[Desert Sasqwatch]

Unless Lonny announced at the Goblinfest that DF is adding front wing mounts into the Store, all front wing mounts are custom fabrications to fit a builders wants and needs and for the specifications of the wing being used. Do you have the skills and tools necessary to fabricate mounts? If not there is likely someone on the forum who may be able to replicate mounts they have made. But be ready to do some welding, as bolt-on mounts may not be feasible.

 

[Ross]

Here is the short frame from Lonny. DF was playing with the rear engine mounts at the time, so the tubes there are a little off from our production frames.

The file is too large (10.9MB) to put out here on the forum, but I can email it to you if you want.
It is a CAD file with a *.SLDPRT extension on the file.

 

[KingChuck24]

That's wonderful of them to release that!

 

[GoblinGuyZ]

Does anyone know how much it would cost?

Edit: I'm stupid the link says 2,250, that's extremely expensive...

I'm happy to put $22.50

1 down, 99 to go lol

 

[Desert Sasqwatch]

One can hope, but I can't get anyone to get the CG measurements made. Getting an aero profile done might be almost impossible. LOL!

 

[jamesm]

One can hope, but I can't get anyone to get the CG measurements made.

@Desert Sasqwatch what measurements do you need? I'm gonna go though my alignment bits after I put my new wheels on this week so I'll have the car in my shop with a tape measure in hand.

 

[Desert Sasqwatch]

Need a 4 corner scale to make the CG measurements. Weight of each corner is taken, the rear of the car is lifted 10 inches and the weights on the 2 front scales is taken. There is a formula that these numbers are plugged into to get the height and fore-aft position. There is an on-going forum thread with this request, that gets refreshed by me every several weeks.

 

[jamesm]

Ah. I don’t have a set of corner scales.

 

[Desert Sasqwatch]

NP. Not many have them - they are expensive!

 

[KingChuck24]

NP. Not many have them - they are expensive!

I have a friend with them, he's a car meet friend though so I won't see him until the spring. I could get the measurements then though possibly.

 

[jamesm]

I’ve considered buying a set, I just don’t know how much I would use them.

 

[KingChuck24]

I found some you can rent for 2 days and its 350 which is pretty expensive but I guess if you don't want to buy the whole set it might be worth it.

 

[jamesm]

Ouch. These are the ones I’ve been eyeing. 1250lbs per corner should be plenty of capacity for a goblin

ProForm 67650 Vehicle Scale System Kit with 14-1/2" x 9-1/2" x 2-1/2" 4-Scale Pads - 1,250 lbs. Capacity Per Scale https://a.co/d/1bxpUl9

I’ve looked at all kinds of other scales to try and find something that would work and be cheaper but haven’t found anything yet. Bathroom scales don’t have enough capacity for the rear. 800lb capacity shipping scales are $150-200 each.

 

[Waterdriver]

One can hope, but I can't get anyone to get the CG measurements made. Getting an aero profile done might be almost impossible. LOL!

Given the corner weights some have shared like Ccnax, Maybe this calculator gives you the approximate CG.
Of course anyones Goblinbuilt with different components will be different, and of course yours with all those speed holes. Lol.
Hope this helps.
Site is RacingAspirations.com . All kinds of calculators to make your mind turn to goo.

 

[Desert Sasqwatch]

The various weights supplied by several builders has been used to locate the fore-aft CG location - directly under the fuel tank, give or take an inch or so depending upon which model. The measurement to locate the vertical CG is the critical one that is needed. This requires lifting the car a specific height and the weights of the two tires on the ground to determine the vertical component. This must be known to set up the suspension geometry correctly.

See this discussion for the CG measurements thread Goblin Center of Gravity in general discussion - so we don't hijack this discussion about aerodynamics any further.