Splitter Leading Edge Reinforcement

So far I’ve been loving the new splitter, however because of the nature of the DiBond, the leading edge is a bit soft and has taken a few licks. I borrowed an idea from a couple people in other classes, and put a reinforcement / trim strip along the leading edge of the splitter.

Lowes sells aluminum channel to “trim” 1/4″ ply (which happens to be the same size as the dibond my & their splitters are made of)
This will make the leading edge much less of a wear surface. Bending and pie-cutting this stuff in a way that doesn’t cause stress fractures, and slotting it to clear the mounts is a royal pain, but it will add a ton of longevity.

I reinforced both the front and rear edges. The front is to protect the leading edge of the Dibond. The spar across the rear is to add a little more rigidity along the ‘long’ side of the splitter.



The fact that it looks a little Mad Max-ish doesn’t hurt either 😀


Big-Boy Welding Table

I have a few projects coming up that really need a decently flat surface to build on. While it’s served me well, the flimsy $30 Harbor Freight welding table just wasn’t cutting it in the long run (it has since been donated to a friend’s son who’s going to school as a welder).

Enter WeldTables.com and their CertiFlat tables. After pricing material (since I don’t have that much scrap laying around), I realized I wouldn’t be able to build a table for the price of one of theirs. I went for the 2 x 4′. Big enough to do what I need, but small enough (and on wheels…) that I can stuff it in the corner of my workshop, or in the driveway, should I need the space.

It came in far quicker than their advertised 7-10 day lead time, and once it did I set about cleaning all the parts with Acetone in preparation for welding it together. It really is a man-sized erector set 😀



We did hit a slight snag that, in retrospect is obvious from the photo above, but we didn’t catch it until we were doing the final assembly. It turns out that they sent leg stringers for a 2×3 foot table, so the short sides were fine, but the long sides were about a foot short:



A quick call to  WeldTables.com and they shipped the correct parts out straight away. The mistake was annoying, but their Customer Service in correcting it was outstanding.

With the correct parts in hand, I completed assembly and welding. I then flipped it over, did a little grinding of the few spots where the weld went higher than the slots, cleaned up the surface with a polycarbide wheel and sprayed it down with some WD40 to prevent rust from building up.



I also ordered a couple of their 6×6 FabSquares and broke the new table in by putting those together. These will be super useful in the future.



What with the Atlantic separating us most of the year, I don’t get to do too many fun projects like this with my Dad. Because of that, so I put a little something together to document it.

Aero: Front Splitter V2.0

After last season, Splitter V1.0 was seriously trashed. Placed on a flat surface, there was almost 2″ of bend across its width, so at a minimum I had to replace what was there. At a maximum, it was time for a complete rethink.

It was definitely time for a complete rethink.

So, based on what I’d learned making and repairing the first one, I set about replacing every single component save the 2 quick release pins. I didn’t intend for it to be that thorough of a redesign, but during the offseason, if there’s opportunity for improvement “while I’m in there,” you might as well take advantage of that.

Part 1: The Rear Chassis

These were the pieces I had far and away the most trouble with last season. They were not adjustable, so once I eyeballed the height the 1st time, that’s where they lived. Furthermore they were difficult from a maintenance perspective, a once you hit something hard enough to bend them, the only thing to do was attempt to beat them straight with a hammer, or completely re-build them. There had to be a better way.

This piece took a bit of evolutionary engineering, but I think the result will be up to the task. You can see V1.0 on the left, bent in a couple different directions, and very unwilling to be bent back straight (especially along the longer edge).



Instead of having a single piece mount, I decided to make a very strong mount to the chassis, with weaker sacrificial hooks to take the brunt of any larger impacts. The hooks are very easy to remove & replace, and to manufacture. The hooks are simply a length of 3/8″ threaded rod, and a short bent piece of steel round bar.



A quick bit of welding and I have (what I hope to be…) a season’s worth of replacement. Hopefully more.



After a bit of time on the drill press and a coat of Machine Grey, and the chassis mounts are done.



Part 2: The Rear Splitter Mounts

The Hooks on the splitter that held it onto the chassis mounts also took a beating last year. Also, their geometry meant that with a good bit of load on the front, the rear hooks would lift off of the mounts. Unlikely to happen under real world conditions, but also suboptimal.

Given that, I went with stronger material (1/4″ Aluminum, up from 1/8″), and a more angled hook design that keeps it located both horizontally and vertically.

After a bit of figuring, this was the design I came up with. The bottom 3 holes are 1/2″, and the top one 3/8″ to tightly hold onto the chassis mounts.




After a bit of cleanup and fitment testing, these are complete:



Part 3: The Front Chassis Mounts

The front chassis mount (under the front bumper) has always been a pain. It allowed for no deflection (which meant bent front splitter struts), and because they only had 1/4″ holes for the quick-release pins, they were very finicky to get everything lined up with.

Inspiration from this came from a relatively prestigious place: The Dodge Viper ACR. I noticed that it had a mount that’s basically only rigid when downward load is put on it (ie: aerodynamic load), but would allow for upward deflection (ie: for off course excursions) to prevent the struts from taking all of that strain.

Here’s what I came up with. The D-rings are completely rigid in tension (ie: aero load), but will allow for deflection (ie: bigger cone strikes or bottoming) to hopefully prevent bending the struts. As an additional bonus, the target I’ll need to hit in order to mount the quick release pins is orders of magnitude larger, which will make mounting the splitter at the track far easier.



Part 4: The Front Splitter Mounts & Struts

The front splitter mounts did the job, but were a little small in surface area against the splitter. They were also short legs, meaning that the nuts for where it bolts to the splitter and where it bolts to the struts were practically on top of each other. I used the miter-saw I received as a Christmas gift to throw these together (shown with a spare set):



I also found some turn-buckle rigging forks on Amazon that, with a little bit of drilling and welding, I was able to make into a pair of new front struts.


Part 5: The Splitter and Final Assembly

Finally, we get to the splitter itself. Using the laminated sheets of DiBond ended up being both a ton of work, and fairly ineffective. After the rigors of the season, the bottom sheet was fairly worn down (another casualty of non-adjustable rear mounts) and it never was as stiff as I would like.

After consulting with some buddies who know more about this stuff than I, I decided to go with 1/4″ Dibond. The single 1/4″ sheet is far sturdier than the laminated 1/8″ sheets.

The first step was to make cleaner (and thicker) buck for the splitter. The lines on the 1st one weren’t all that clean. This will make for fairly quick & easy replication with a router & a flush-trim router bit.



I picked up a brand spankin’ new sheet of 1/4″ Dibond, and we managed to cut 3 splitter blanks out of it, then trimmed them down with the router. It’s a super dirty process, but it is super effective.




Instead of using sections of the Home Depot Racing Supply paver edging for the air dam, I went ahead and used the whole one (so it would be more rigid), then we riveted the original air-dam to it to use for mock up, to then make a pattern (and buck) for a new design:




Once all the mock-up was done, it was time to disassemble the whole thing and put the “real” parts on. All of the parts were mounted using elevator bolts.

I made a spacer to use with a nut and a washer stack to pull each elevator bolt into place:



After a bit of sweat equity, this is what the bottom looks like. The nice thing is that they have very thick bases, which allows them to serve as something of a wear surface without sacrificing too much strucutral integrity, as opposed to using button head bolts, which have much less metal to wear down before they’re rendered useless.


With the base complete, we used Clecos to temporarily rivet everything together…



And then finally completed assembly and riveting, and got it mounted in place:



It was a ton of work but now that I have a good, solid design, replicating it will be relatively straight forward. Hopefully I don’t find any crazy weaknesses with this design that’ll require another complete rethink.

LiFePO & First Start

After last season, the old ATV / lawn tractor battery was getting a bit long in the tooth (and in the start…). Battery tech has made huge leaps over the last 5 years, and the trickle-down from that has been absolutely astonishing. Where I used to put up with 120 CCA out of the ETX-9 because it was, at the time, lightweight and fairly affordable, for not much more money I can have something that weighs 1/2 as much and puts out 3x the CCA.

I went ahead and snagged a Battery Tender 360 CCA LiFePO to see if the new tech was all that it’s cracked up to be. I clearly have little long-term experience with it, but near term, man does it get the engine fired up quickly.

The other big advantage?


Less than half the weight. It almost feels like a toy.

A couple small tweaks to the battery tie down bracket were needed as we took advantage of a notch in the ETX-9 to locate it on the bracket that the Battery Tender doesn’t have. Fortunately its footprint is marginally smaller, so the already cramped space for the battery wasn’t a hindrance.

And with that, a small milestone was reached. On January 18th, the race car cranked up for the first time this year putting me miles ahead of where I’ve been in the past.  The alternator / WP belt needed a bit of an adjustment (something I’d forgotten it needed at the end of last year then forgotten), but now she should be good to go.

It’s been a minute since my last update, but I’ve been making a bit of a mess in the workshop during the offseason.

More to come on that later.

Control Arms & Avons (again)

It’s been a long break, but after getting absolutely every possible run out a set of Hoosiers, I wanted to try another readily available set of tires. Around the same time, Paco Motorsports’ trick adjustable Rear Upper control arms went on sale with some factory seconds (ie: cosmetic blemishes).

I’ve coveted them for a while because the stock rear adjusters tie toe to camber, and these allow you to do 2 really interesting things:

  1. Adjust toe and camber individually.
  2. Play with suspension geometry a little bit. Because the upper rear arm is nearly infinitely adjustable, you can use the stock alignment cams to set toe, but also set track width, and then compensate by making the upper arm longer or shorter to maintain your alignment.
  3. Easy, consistent adjustments. Each 180° turn on the control arm translates to a 1/4° change in camber.

It’s one of those things that gives you plenty of rope to hang yourself with, but if you take your time and plan out what you’re doing (and take lots of measurements), you can do a lot of good as well. Which means I’m probably going to end up metaphorically hanging from the end of that rope…



There were some concerns about the strength of the threaded components, so I took a few measurements. The gist of it is: the shaft is 3/4″ diameter, and it is a fully threaded sleeve on the control arm portion so there’s thread engagement far beyond the front and rear “nuts” it looks like it has. Barring some weird metallurgy issue, these should be plenty strong.



Finally installed with the car. Between the adjustable upper arm, the adjustable offset upper-outer bushing (in the knuckle) and the stock cam adjusters, there’s a lot of adjustment now built into the suspension to make (or break) the setup.



On to the tires: There is a readily available Formula Atlantic (I think?) Avon A11 compound Radial Slick in a 240/600R15 size. It’s about 1/2″ taller and wider than the Hoosiers I’ve been running. I’m not thrilled about the taller bit, as it may end up with some interference with the chassis, but the wider should be nice. And they allegedly last longer than the Hoosiers, while being as easy to get.

Ideally, I’d be on a 275/35/15 Hoosier A7 or a 21.5 x 10.7 x 15 Avon, but those are friggin expensive, and unobtanium on the used market, so I’m going to see how these do, then end up settling on either these, or the 23 x 9.5 x 15 Hoosiers after this set.

And finally, last night I had a buddy come by to help drink my beer and measure while I adjusted from under the car. While the last set of tires wore fairly evenly, it was apparent that the rears needed a little bit more camber, and the fronts needed to be adjusted. I think they got knocked out of alignment over a couple big bump at an event, because we found about -1.5° degrees camber on the left side and -3.5° on the right. Definitely not ideal.

After roughing in the rears to be even, I threw the “Me Simulator” 210 lbs of steel plates into the driver’s seat and we got to work. The alignment numbers I ended up on are:

Front Camber: -2.75°
Front Toe: 5mm out
Front Caster: as much as I can get away with and hit my camber number…

Rear camber: -1.75°
Rear toe: 0″

We’ve got an event this weekend so we’ll see how she runs, and go from there.


Splitter Repair

The only casualty for me from the Chasing the Dragon Hill Climb was the front splitter mount that broke at the end of my last run.



One of the cables apparently bounced and got hung up on something that kept it off the ground, but the other ended up dragging on the ground.



This necessitated making at a minimum a new cable-strut, but I wanted to try something different using fairly thin steel bar and a turnbuckle.

Perusing the aisles at Home Depot Racing Supply revealed these 50 inch x 3/16″ rod turnbuckles for supporting screen doors. With a little work, it appeared I’d be able to use the cable end terminals from Harbor Freight that I used with the cables as well. After a little work with a cutoff wheel, drill (to get the holes in terminal ends sized to the 3/16″ rod), a little sanding and welding… and a trip to Ace to get left-hand thread jam-nuts, and here’s what I came up with:



This will allow easy adjustment both now, and at the end of the year when I rebuild the splitter completely, probably out of wood. It also allows some flex should the splitter hit larger bumps as the cables did, as the 3/16″ rod is fairly flimsy. It’ll do the job, but it’s not exactly going to hold the weight of the car by itself.

With the support side done, I needed to remake the mounts stronger than they were before. Instead of fiddling around with rivets and rivet-plates, I went big. An acquaintance recommended using elevator bolts for this, something I’d never actually heard of prior. Turns out, McMaster carries them (of course they do), and they’re pretty stout. If these fail, then the splitter itself has broken.

I was concerned about it spinning in the dibond when I tried tightening them, however the domed base dug in nice and strong to the bottom. I also used some thicker (1/8″) aluminum angle for the top side where it would meet the new strut.

And finally, the finished product. It should work until the end of the year. We’ll see what V2.0 brings when the time comes 🙂


Event Report – Chasing the Dragon X

Well, it’s finally happened. After almost 2 years of prep and a ton of help from a ton of friends, all the stars aligned and I was finally, FINALLY able to make my first Hill Climb.

Honestly , just being there with my car in good health felt like a massive win after all the bumps in the road leading up to this weekend.



The weather forecast was perfect, but you never know in the mountains so I brought everything but the kitchen sink. The little Honda generator and shop fan were invaluable in keeping our drivers cool during down-time between runs. We paddocked and shared a cabin with Heikki (Turbo Miata powered Locost 7) and near Lars (Factory Five Cobra NASA Challenge).





Friday included loadout at the paddock spaces, registration, and my car’s first Club Racing tech inspection. Everything went smoothly and I ended up, as hoped, with my car’s brandy-new Logbook number stamped into the roll cage.



With the formalities out of the way, we beat feet back to the cabin for some brews and a bonfire under the stars.



Saturday ended up being one of the most fun days I’ve ever had racing. After I got the butterflies out with my first couple of runs, I was able to make steady progress on the time sheets. By the lunch break I was in the top 10 overall.

I kept progress pretty steady through the day. I lost the time slip for my 142 second recce run my 1st time up the hill, but other than that, progress was steady as I felt out what the car liked on the bumpy surface, and where I could push and carry more speed.



By the end of the day, I was 1st in class and managed to snag a spot on the leader board. I knew a few of the faster cars were struggling with gremlins (including eventual, and multi-time King of the Hill Heikki), but I could not be happier with how the day went.


At the close of day 1, it was definitely Beer O’Clock, then off to the worker appreciation party in Robbinsville.

For me, Sunday was a relaxed, fun day. As far as I was concerned, I did the work I wanted to on Saturday. I ended up ripping off a flyer the last run before the lunch / quiet time break that chipped a few tenths off of my Saturday fast time, but mostly ran consistent, fun 130 second runs while playing with line choice through the corners.

That change in line came back to bite me in a small way leading to the only real issue I had of the weekend, where on the final run of the day I hit a bump through the spectator section I had previously missed that knocked 1 of the front mounts for the splitter off. By the last sequence of corners, the second mount had also failed as I could hear rubbing but everything felt ok on the car. At the top of the hill I removed the splitter for the run down. Thankfully it will be an easy fix that I already have better designs for.



It was in good enough shape to hang on the car (with some help) for the tow home:



After that minor bummer, we packed up and headed to the trophy presentations.

The King and Queen of the hill were crowned and received engraved stainless steel swords for their efforts:



And I took home what I feel like was one my hardest earned wins given the family health issues and car trouble and effort it took to even show up on the mountain. And I couldn’t have done it without the help of a huge number of folks who I can only try to thank enough.


Check out my full album of the event HERE. There’s some REALLY cool hardware at these events.

This was my fastest run up the hill.


And again, because I literally cannot say this enough: thanks again to everyone who helped get me and the car to this event, and to the CCRSCCA & SEDiv Time Trial organizations and the corner workers who worked their TAILS off putting on this event.


EDIT: A friend tracked down the overall event records and times, and found out that I was only 0.5 seconds off of the SPU class record. As though I needed motivation for next year! Maybe I’ll pull the ballast and corner balance the car (for the different weight) next time 😀