Post your DIY aero pics
#1101
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I don't think I have pics of it but on Sean's we did a similar thing in the rear to what JPreston did in the pic he linked to except we made a steel bracket that attached to the splitter and the bracket slotted above the front subframe lip instead of the splitter itself doing that. That allowed us to run the splitter lower than that point.
Jpreston's is an example of brackets sufficient for an undertray only - no extension forwards of the bumper. You don't need much in that situation. However, it would not hold up well in offs. Dip two off where there's a bit of a drop to the dirt or find yourself straddling big rumble strips.. anything that pressed up on the splitter against the car's weight, and the straps that serve as brackets will likely fold/compress. Although, his is a bit higher than we run ours, so in his situation you might hit the subframe first.. (BTDT)
Jpreston's is an example of brackets sufficient for an undertray only - no extension forwards of the bumper. You don't need much in that situation. However, it would not hold up well in offs. Dip two off where there's a bit of a drop to the dirt or find yourself straddling big rumble strips.. anything that pressed up on the splitter against the car's weight, and the straps that serve as brackets will likely fold/compress. Although, his is a bit higher than we run ours, so in his situation you might hit the subframe first.. (BTDT)
#1103
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Thanks for the advice guys. Picked up a 4x8 of 1/2" birch, 8ft of square tube, and a gallon of kilz. I was going to just do an undertray but I don't want to have to do this twice.
Would a front splitter and no rear aero unbalance the car significantly? I plan to make it easily removable, so I could always give it a shot and take it off if its too much. More front grip sounds nice though.
Would a front splitter and no rear aero unbalance the car significantly? I plan to make it easily removable, so I could always give it a shot and take it off if its too much. More front grip sounds nice though.
#1107
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Hmmm. Good to know. What would you consider a very small splitter. I won't be running an air dam, just a regular NA front end.
Maybe I'll start decent sized and bring my battery powered jigsaw to the track. Cut off splitter material until it balances
Maybe I'll start decent sized and bring my battery powered jigsaw to the track. Cut off splitter material until it balances
#1110
For those thinking of bamboo, I considered it a year or so ago and found a local exotic hardwoods place and they had about 60 sheets of 1/4" stuff, I think it had 3 plys, definately not 5 ply. They basically wanted to give them away at $20 per 4x8 sheet, they had apparently been sitting for a long time because some rich guy ordered them but didn't get them exactly on the day he was promised, so cancelled on them and refused to pay. They weren't stored very well so they had some waviness.
Unfortunately, they were not stiff at all. They were pretty flimsy. This is just 1 data point though, it could have been because of weak glue or because the storage conditions, or many other factors. It was very pretty though!
If you look up stiffness values for bamboo, it should make a great material for a splitter, not sure why the stuff I found sucked.
Edit: just remembered the stuff I found was horizontal layout. I think vertical would be more stiff.
Unfortunately, they were not stiff at all. They were pretty flimsy. This is just 1 data point though, it could have been because of weak glue or because the storage conditions, or many other factors. It was very pretty though!
If you look up stiffness values for bamboo, it should make a great material for a splitter, not sure why the stuff I found sucked.
Edit: just remembered the stuff I found was horizontal layout. I think vertical would be more stiff.
Last edited by Dustin1824; 04-04-2016 at 05:27 PM.
#1112
The big part stays under the bodywork, and the small splitter can be removed somewhat easily
#1115
Did some more searching today in the name of science.
1/4" bamboo plywood can come in single ply, 3 ply, and 5 ply. I found out that 3/8" thickness is pretty rare.
Aside from that, it can come in a horizontal layout or vertical layout. Keep in mind the layup can also be optimized for being stiff along the length or the width, just like any plywood and also composites. Cool stuff, but it's pretty expensive right now and not many places have it.
1/4" bamboo plywood can come in single ply, 3 ply, and 5 ply. I found out that 3/8" thickness is pretty rare.
Aside from that, it can come in a horizontal layout or vertical layout. Keep in mind the layup can also be optimized for being stiff along the length or the width, just like any plywood and also composites. Cool stuff, but it's pretty expensive right now and not many places have it.
#1116
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I'd still check it out. Ryan, you've seen the aluminum tray under the front end of my Catfish, right? It bolts to the front bodywork and then is connected under the steering rack with the two M6 nuts that are sitting there. Have you guys considered doing this for your cars, and then just making an edge splitter that extends from the front of the car?
Aluminum isn't a popular splitter material. I'm a BIG fan of aluminum in general, but I don't like it for this application... You have to go way too thick (heavy) to get the rigidity you need.
0.125" thick (rough guess) aluminum at ~1.75 lbs per sq. ft. doesn't win any weight contests, and that's still not nearly rigid enough at that thickness to extend very far beyond the bumper without additional supports. I'm not doing the stand/bounce test on a 0.125" aluminum splitter edge...
Re: removable extension, I've thought about it before, but the answer has always come down to it just adds unnecessary weight. You have to overlap the two layers a considerable amount to get enough rigidity in the layer that extends outwards of the bumper, and all of that double-thickness is twice the weight of what you'd have had there if it was one piece. And again, now you need a substantial amount more support along the outer edge than you would've needed if it was all one continuous piece - we can run more than 6" of extension beyond the airdam without any support at all.
My current splitter transitions to half thickness in all the portion behind the bumper. At ~0.75 lbs per sq. ft. that is hard to beat without going composite.
Last edited by ThePass; 04-05-2016 at 01:17 AM.
#1119
Not really 100% DIY since I bought the diffuser off a buddy but whatever.
Dollars spent: $180 (diffuser, paint, and splitter rods)
Hours spent: 20-25
How effective: 2
Materials used: Paint, l-brackets, u-bolts, windlace, edge trim, splitter rods, and diffuser
Tracks tested on: None but will be tested at Thunderhill this weekend
Race/TT class built for: Just HPDE, nothing serious yet
Dollars spent: $180 (diffuser, paint, and splitter rods)
Hours spent: 20-25
How effective: 2
Materials used: Paint, l-brackets, u-bolts, windlace, edge trim, splitter rods, and diffuser
Tracks tested on: None but will be tested at Thunderhill this weekend
Race/TT class built for: Just HPDE, nothing serious yet