Building our Lemons/Chumpcar (Page 4/29)
La fiera DEC 23, 04:31 PM
Great work guys!! I drive a Civic chump car in certain races here in the south east. It is not my car, I pay my share to race.
It is between $800 to $1000 depending on the venue. That covers the entry fee, the gas and the car per driver. If you need a driver for a couple of endurance races you can count with me. I have a track day Fiero and I would love the opportunity to drive one in a race.

Rei Moloon

[This message has been edited by La fiera (edited 12-23-2012).]

DonP DEC 23, 07:59 PM

quote
Originally posted by La fiera:

Great work guys!! I drive a Civic chump car in certain races here in the south east. It is not my car, I pay my share to race.
It is between $800 to $1000 depending on the venue.



Yup, this cheap racing isn't all that cheap. Until you compare it against other series and venues. Both Chumpcar and Lemons do have a fairly high entry fee. But you have to factor in the fact that there is no front gate to cover the overhead.

But another option that you are talking about is the option of buying a ride. The Lemons guys require a minimum of 4 drivers per car. That sounds weird until you think about the fact that the shortest (and most common) races run right around 7 hours. Most drivers will be in the car 1.5 - 2 hours at a time. As you know La Fiera, that's a LONG time to be in a race car. Anyway, often times a team may lose a driver for a given race for whatever reason and may elect to offer a seat for sale to spread out the costs. I talked with a guy at Sears Point last year that was participating in his third "arrive and drive" event that year. He flew in with his safety gear and a check and had a great weekend. The risk here is that the first driver can total the car in the first turn and nobody gets a refund. There's a specific area of the 24 hours of Lemons forum where many folks offer seat time. http://forums.24hoursoflemo.../viewforum.php?id=11


Being based in Reno, we race at the northern California events. I'm lobbying to make the trip to Portland, OR as I consider that my home track when I first started racing. Don't think the lobbying will work, however.

Have fun in the Civic!

Don

[This message has been edited by DonP (edited 12-24-2012).]

DonP DEC 24, 03:59 PM
Now that the main structure was finalized, we set about adding door bars. Because we have raced and been hit before, there was no discussion about doing anything less than the full NASCAR style door bars. We chose to have three parallel bars joined by small stand-offs. In addition, there is just no way we would have the bars inside the normal cockpit area. First of all, if I am going get hit, I want some room for the bars to give before getting to the driver. But more importantly (and honestly) I'm too big to fit with the bars that close.

If you are going to use full door bars, a quick disconnect steering wheel is required. Trust me.

Robert took the first guess at where we needed to cut the doors inner panels. That would be modified on a regular basis as we went on. Plasma cutters are just too cool!




There is a commonly seen practice to build door bars with a compound bend such as seen in this photo. I found this post on the 24 Hours of Lemons Forum, so want to give them credit.


And we have problems with the design. In a significant impact, I feel that this type of s bend is more likely to bend into the passenger compartment. For that reason we chose to limit bends in a way to direct the energy from a significant impact. In order to do that, it was necessary to notch the door jambs. Again, I think this is a reasonable trade-off.







We moved the interior door release to the side impact panel. Yes, we tried to keep the door skins operational as doors. It's a bear to climb out the window. The top door bar is lower and stronger. We need all the help we can get. Yes, that is the passenger side. We are building the car with the possibility of having a passenger riding along and screaming from the right seat. We planned for ride-along instructors at SCCA and NASA events.



So, our final door bar install looked like this.




DonP DEC 24, 08:46 PM
The rules require a pair of down tubes at the back of the cage. These are supposed to connect to the top of the main hoop and extend down and back at as close to a 45 degree angle as possible. In our case, this allowed for the braces to terminate at the rear strut towers. We made spreader plates that wrapped around the top and front sides of the strut towers.



The rules do not specifically prohibit forward running tubes from the dash bar to the front frame. But we couldn't think of a way to make them work.

The biggest piece still missing from our build is the cross bar going across the main hoop. This is an important strengthening bar as well as one that provides a mounting point for the seat belts. Because of the shape of the rear structure and where the rear glass fits within it, the main hoop cannot fit flush to the rear bulkhead. And because we needed to allow the seat to be as far back as possible, we elected to modify the conventional design for this brace. Typically the cross bar and angled brace intersect on the same plane. The cross bar is cut and fish-mouthed to fit the angled bar, and everything is welded solid. We decided to take advantage of the space between the angled bar and bulkhead. So Rich bent a tight radius kick-back to run the cross bar behind the rest of the main hoop. You can see how that looked out of the car here.


In the following picture, you can see the bar offset. You can also see some fixtures that we have added to the bar. The squared off piece is a bracket to hold the seat back bracing. It's adjustable for two different seat positions. What's more interesting is the two conical looking fixtures. These are tapered "bungs" produced by UB Machine. Ub makes a ton of race related hardware pieces. These bungs have internal 1/2" threads for bolting a race harness to the cage. The wider base has a radius to match the cage and are welded on in whatever position you need. The bosses are here http://ubmachine.com/bosses.html


DonP DEC 25, 11:34 AM
It was time to start mocking up the dash. Initially we planned on building something like the "Chariot of Fire" build http://www.fiero.nl/forum/Forum1/HTML/085472.html. That's a pretty standard way to deal with the whole issue. But I think our concerns about looking like we had done too much modification to the car kicked in. That and we found that the stock instrument pod could fit (and it was already paid for.)



But we needed some additional gauges. So we extended across the dash towards the right. Ultimately our finished dash looked like this. The two tabs below the add-on gauges are to hold the fire extinguisher.


That meant we had to plan ahead and add some sort of mounting structure. Here are a couple pictures of the simple mounting braces. In the second photo, just at Rich's left elbow, you can see the brace we installed to hold the dash pod. We used nutserts to bolt the sheet metal to the braces. Nutserts are cool. They are in essence threaded pop rivets. Great for blind holes that need to be threaded, particularly in material too thin to accept a tap.




Nutsert image
kwagner DEC 26, 09:09 AM
Very nice! I know this won't help you guys since you did this work already, but in case it wasn't mentioned in the other threads, Doug Chase told me he would drill holes into the floor and drop the cage down into it. Then he could weld 360 around all pieces, lift the completed cage into place, and then weld plates on the floor to cover the holes and mount the cage to the floor.
DonP DEC 26, 12:28 PM
Yeah, that's a common approach. I've seen several "Street Stock" type cars use that trick. But we tried hard to maintain as much integrity on the shell as possible. But we thought of it! Chase does some nice work, we really scoped out his pictures before the actual build.

Don
DonP DEC 26, 12:53 PM
Now here's where it got interesting. To this point, the cage is mostly just tacked together. The intent is to get everything in-place and fitting before doing the final full weld. Anybody that has finish welded a cage inside the car can testify to how much a pain the process is. It is mandatory that all welds completely circumnavigate each joint. And the quality has to be good to fulfill the requirements of a race cage.
Did you know that you can remove the cage from inside a Fiero, weld everything together out in the open, reinsert it back into the car leaving just a handful of welds to complete.
Well, we gave it a shot.

First step was to break the tack welds where the main hoop joined the halo and the floor plates. That allowed us to snake the main hoop out. Okay, we removed the door bars before even attempting this. The only way (I think) that it can work is with the back glass out of the car.




Okay, to be honest, we had not yet thought of trying to remove the front half and top of the cage. Our intent of removing the main rear hoop was to allow us to pivot the rest of the structure back to gain access to all joints. You can clearly see that the joints were just tacked together.




But we started snaking portions out of the cabin to gain easier access.







Finally came the realization that we had more of the cage outside the car than in. Again, we had earlier tacked the door bars in place, and removed them. Had we not done that, I don't believe we would have even thought that removing the main structure would be possible. Oddly enough, we could get it out of the passenger side, but not the driver's side. I think that was because we had fudged the halo towards the driver's side for greater head clearance.




Welding became an easier proposition. That's the main hoop hanging in the back. It's been fully welded, cleaned, primered and painted.



The rest of the cage painted and ready to reinstall. If you look closely, you can see where the paint stopped in preparation for final welding once back in the car. Our choice of paint is the Rust-Oleum "stainless steel" paint we pick up at Lowes. It gives a nice clean look to the bars. Just our choice. The picture below is still in primer.

[This message has been edited by DonP (edited 12-26-2012).]

DonP DEC 27, 02:06 PM
Once the cage was welded and painted, we had to snake it back into the car.







From there, we basically set everything in place, with the main hoop being the keystone for the whole thing. We fit and tacked the main hoop to the floor plates which were solidly mounted, and then tacked the already welded halo/downtubes/dash bar structure to the main hoop. And then, without welding the front downtubes to their corresponding base plates, we tacked in in the door bars. We actually had to use a ratcheting tie-down strap to pull the front tubes back towards the rear hoop and make the door bars fit tightly. We then broke the main hoop tacks which allowed us to shift the entire structure inside the passenger compartment. Moving the structure gave us access to weld fully around the door bars. Once we had the door bars fully welded, we moved everything back to the final position and welded the main hoop and front down tubes to their respective floor plates/spreaders. We were lucky to have someone who has been building race cars since the '70s as Rich was able to plan out each step in the process.




Note to self, wire brush the floor pan, rear bulkhead and sills BEFORE welding in the cage. I spent quite a bit of time with the wire brush cleaning all the surfaces. I cannot weld, but I can clean. It was definitely cramped with the cage installed.




But we did finally get it cleaned, primed and painted. Again we elected to use the Rust-Oleum "stainless steel" paint for the complete interior. With all the sheetmetal exposed, black would be too dark. And we like the clean and bright look of the stainless steel.



Notice that we masked off stuff that we wanted to keep from being painted. Here we had plastic bags over the pedals to keep the pivots clean. We also masked off the windshield inside and out before painting.




On the picture above and below, you can see side mirror mounts we installed prior to painting. We didn't want to rely on the stock side mirrors as they are too exposed in the case of impact.

[This message has been edited by DonP (edited 12-27-2012).]

DonP DEC 28, 03:32 PM
Prior to starting the build on our cage, we took a trip to both summit racing and Harbor freight to check out their tubing notchers. They looked to be very similar and we picked up the slightly cheaper unit at Harbor Freight. It's neat to have these guys both right here in town. The first thing Rich always buys before starting a new car build is a new file. He gets a new 14" 1/2 round file to deburr all tubes joints. If you were to watch the build, it would be surprising how much work is accomplished with a new sharp file.


Before putting the tubing bender away, Rich tackled the front and rear bumpers. We knew that we couldn't slap a cattle guard on the front and back and call it good. It just wouldn't fly with this type of racing. At the same time, it just doesn't work to leave the bumpers ignored. That's when we found some inspiration in the "Team Pontiaxed" build here on the forum. I cannot find a link, but they removed the egg-crate behind the nose and welded what appeared to be a race-inspired tube bumper with two parallel bars and stand-offs. With the nose reinstalled, all was hidden behind the plastic. But they used an aero nose which looked to allow more room and better air flow. so we found an aero nose.


We have a big debate on the team about the aesthetics of the standard Formula nose versus the aero nose. I come down on the side of the standard nose. Rich on the side of the aero nose. Robert wisely wants nothing to do with the discussion. In any case, the aero nose wins out for the on-track application.

Rich made a template out of light EMT tubing and then started bending the full-size tubing to match Behind the plastic egg-crate is what we believe to be spring steel. No way to easily drill through this material. But we could weld to it. So he got to work on making the bumpers. The final bumpers was made of 1.25" tubing at .081" wall thickness. Didn't have any .093 on hand or we would have used that.



This is the rear bumper. You can see the cut out in the center of what is the lower bar. That cut-out accommodates the license plate pocket in
the rear cover.



He used two pieces of angle iron that welded to the original steel structure. From there, he made a couple of standoffs to kick the bars forward to the point that they are just in contact with the back side of the plastic nose. He bent two bars that follow the contour of the nose and are welded to the standoffs.



Checking the fit

[This message has been edited by DonP (edited 12-30-2012).]