Budget C5 Corvette Racecar

[monteboy84]

05-16-2014
Here's a sneak peek of the fancy new switch panel that I designed and had laser-cut last night at work. Made of .060" aluminum, mounts 6 waterproof switches with individual fuse holders as well as 3 12v power ports below. I put in holes for gauges right now but don't know if I'll actually use them or not. This panel fits in place of where the original radio and hvac control were mounted before. I feel like I should paint it or something, but that seems like it might start me down the slippery slope of waxerdom. One day it's a painted switch panel, next thing you know I'll be running airbrushed FRC's :toetap:

[monteboy84]

05-20-2014
Wowzer, crazy weekend working on the car! We had planned to test at BIR yesterday, but after dad and I worked until midnight on Friday and 8am-2am Saturday, we finally pulled the plug at 3am yesterday morning and accepted the car wasn't going to be far enough along for the test day to make sense. That being said, we made a ton of solid progress and the car is to a stage of completion that I'm very happy with, we'll be able to easily have it race-ready next weekend in preparation for a last-minute test/shakedown day on the 30th and racing on the 31st. Dick came out to help on the car all weekend as well, he's once of our teammates and was happy to get his hands dirty.

Unfortunately, with all of that progress, my documentation for the weekend is a bit lacking. I've got a couple of in-process shots, but mostly I was scrambling to get stuff done so the camera was an afterthought.

Fitting passenger door bars. I'm pretty proud of this, I had saved my bar template from the driver side, and it was less than 1/8" off when I stuck it in the passenger side. That tells me we did a damn good job of making everything symmetrical in the car.




Welded up!






The notches in the door jamb came out much better on this side, the top one was too deep on the driver side, but thankfully you can't look at both sides at the same time ;)


Fitted and stitch welded the original panels back in place. Had to add some material around the tube to make the fit just right.


Masked the tubes and blew some paint on the filler panel


Both sides done




Halo bar clearanced to fit over the cage and set back in place




Getting ready to weld




Fully rewelded and gave it a quick coat of paint.




Had to notch the new halo piece to clear the cage as well. The bars fit almost straight in line with where the roof pins were, so there will be some work needed to get the roof secured. I also need to seal these notches to keep the car somewhat weatherproof.




3M Windoweld Urethane. This stuff is wild, dad uses it for everything it seems, but this is one application where GM used it originally.




Holding the ends in while the glue sets. We ended up pop-riveting the flange down becase the original screws didn't really hold any tension.






Painted the bottom of the battery mount and threw some foam tape on to keep it from rattling on the fiberglass it sits on.


Mounting tab welded on

[monteboy84]

Welded the battery mount in place, along with the harness loops that I made on Friday. The battery mount is welded to the cage harness bar and the tab I welded to it is welded on top of the panel behind the seats.




Put a holesaw into the filler neck to remove the flapper and 'unleaded' restrictor for quicker fueling on pit stops.


Dad made a perfect cold air box for the intake. He had an SLP air cleaner lid from a 4th gen F-body laying around, turned upside down with an aluminum shroud it will pull plenty of air through the inlet we made in the top of the bumper. This keeps it isolated from the hot air off the radiator and will hopefully help the wee little motor breathe on the track.




Also made a cover for the missing rear tub out of .080" aluminum






Here are the seats and harnesses in place


Aaand some teaser shots of the semi-complete car. We took it down the road and bedded in the brakes a bit, the ST43 pads are insane, it literally feels like your eyes are popping out of your face when you use full braking.


Interior shot






I love love love this car, having a blast with the build and can't wait to get it on the track.

[monteboy84]

05-27-2014
Kicked some butt this weekend! Put in a lot of hours on the car with dad and my gf at the shop, it all ended up with having the car on the road for an 80 mile maiden voyage from my family's shop to my home last night. Now that the major work is done, I can do smaller tasks on weeknights from my garage and simply drive it to their shop if I need to do more demanding projects.

Once again with the rushed pace all weekend, I did a poor job of documenting the process, but I'll share what I was able to capture.

I wired up the battery disconnect switch and ran cable to the rear-mounted battery location. Most C5 racecars have a basic disconnect on the small cable that runs from the battery to the underhood fuseblock. While this will certainly kill the car and a lot of circuits, it still leaves a hot cable running to the starter as well as a fuseblock full of hot circuits inside the car. This will still pass Tech in most series, but I'm not a fan because it's not a true battery cutoff, it's basically a glorified ignition switch. Instead, I opted to use a 6 pole disconnect that kills every circuit past the switch, leaving only the heavy duty cable from the battery to switch as a hot wire. This works by cutting off the battery cable and ignition separately, while closing a path to a grounded resistor in order to protect the alternator from voltage spikes.

Wired up


Ran the cable and ignition wires back along the dash bar


Soldered wire to both leads off the resistor and heat-shrunk it for protection


Mounted to the factory dash bar and grounded


Got an oil cooler adapter from Randy at DRM, this one was used but still in great shape. It gives a convenient port for the factory oil temp sender to thread in as a nice feature alongside the AN10 ports


The truck motor came with a block heater that occupied the exact same space as the oil cooler adapter, so I had to remove it and replace it with a factory brass plug.


My radiator orientation requires a splitter with ducting in order to cool properly, so I started construction on one. Building a cardboard template for this would be tough to do right, so I opted to build the initial design from plywood and then swap it for HDPE plastic later on.


Transferring the nose profile down onto the panel




Added a C7ish profile and cut it out


Test-fitted




Made side panels for the inner ductwork




Mounts to modified swaybar clamps


Assembled with T-nuts to keep the bottom smooth


Starting on the grille insert


Frame tacked together


Rods added for triangulation to stiffen the plywood panel across this opening. This grille frame is steel to keep large debris from getting scooped up into the radiator, I've seen a loose started go through a radiator and hatch a race motor before, best to add some weight and protect the car.


Painted, screen fitted with safety wire, and an angled back panel was added for ducting.






Back on the car


I wish I had pictures of this out of the car, but here's the trans/diff cooler that dad assembled. It has dual Tilton pumps and a cooling fan all mounted on a modular frame so that it can be dropped out of the car as an assembly. Pretty awesome setup, just need to wrap the exhaust in order to keep the heat isolated.


Nevermind the crooked exhaust tips ;)

[monteboy84]

Got the Depo lights mounted as well as the stock corner markers


On the road! Stopped along the way home to check some things over and make sure nothing was melting or rubbing.


Hood is taped down because I haven't mounted the Aerocatch pins yet, classy eh?


Looks especially evil in the dark, waxers will run from my brake dust and water spots :willy:




Well that's it for now, I'm DD'ing the car this week as a shakedown ahead of our May 30th test and race the day after. As you can see, there's some bodywork still needed, particularly ducting the hood, but that will come in time. I also need to fit the window net, sticker it, blah blah blah, but it runs and drives great for now. The coolant stayed at 197 steady and the oil never got over 130 degrees, so on the track it should be perfect. The car is no speed match for my Z06, but it pulls strong, the handling and brakes are phenomenal. It pulled 33 mpg average on the interstate with the stock tune, might be a pretty solid econobox with some tuning :D

Thanks for looking, see you at the track!

[monteboy84]

05-27-2014
Thanks guys! Found some pictures of my swaybar clamps that I forgot to post last weekend. I added the tab onto these in order to mount my splitter. It's a very simple setup but worked great, the whole undertray swings down on these when the cable are unhooked, so it's a simple thing to work on the front of the car.

[monteboy84]

06-05-2014
Well we finally made it on-track. The test day went good and we were able to correct a number of minor issues (power steering cooler, water boiling over on shutdown, insufficient splitter cables, and a few others) in order to make the car reliable. Following testing on Friday, we headed back to the shop to finish last minute stuff like window net, tow hooks, and the seat back brace. It was raining pretty hard Saturday morning, and something got wet on our way to the track, so for the first 20 minutes or so the motor was cutting out around 4000 rpm's. Once things got warmed up it was fine though, and the car worked great.

All loaded up, I actually drove the car to the shop and then to and from the track on the test day.


Final corner weights, I opted to even up the front tires and keep the split on the rears, figuring that this would be the most predictable arrangement.


Cut a hole in the hood in preparation for Heat Extractors from Track Spec Motorsports


Final alignment settings. Some of these were maxed out due to the car's previous frame damage, but thankfully the tires wore very even and the car worked great with these specs.


Hanging out with her sister car




Numbers on






Tow hook on







Rear hook on too


Test day at the track










Here's a cool picture from the race, taken by Alex Bellus, a professional from here in the Twin Cities


Here's a short video as well, the car sounded great


So, with the issues I had early on, I pitted a couple times and managed to go 2-off, causing me to pit again for the grille to get cleaned out. That put us back into about 23rd place, but once the car worked well and I could stay out, I managed to race my way up to 6th place. With a tank of fuel gone, I pitted to refuel and change drivers. We had radio issues so the team wasn't ready in the pits, and our slow stop dropped us to 14th place. Dave ran well and brought us back up to 7th place during his stint, which we held through the driver change and about 1.5 hours with Dick in the car. Unfortunately, Dick had a mishap on track and made contact with a tire wall outside of T13. The damage is all cosmetic, but it took us out of the race for the day. We could have fixed it, but I opted to load up and save the pieces for next time. It needs repairs to the splitter and inner fender, as well as a new fender and bumper cover, but it won't be a bad fix. I should have time to get some paint on it this time as well ;) Oh well, life goes on, next race isn't until 8/9 at MAM in Iowa so I'm taking a breather for a few weeks before making repairs.





Thanks for following along

[monteboy84]

07-10-2014
Welp, after a brief hiatus from sleepless car-building insanity, I dove in and fixed the car up to get it ready for the next (Mid America August 9th) World Racing League event. So far, I have the bodywork repaired and am driving the car, but still plan to build a diffuser and spoiler before this race.

The inner fender took some moderate damage, but it's all hidden by the fender and I had the broken pieces, so I opted to repair it. After roughing up the cracked areas with a sanding disc, I started to lay on some glass and resin.




This area on the bottom front was broken completely off at the bonding seam and cracked up pretty well, so I riveted the piece back on and glassed it in.


Once the resin cured, I did some quick clean-up




...and blew some black paint on it. Nothing too fancy, this is all covered once the fender is on.


I skipped a bunch of steps here, but only because I worked until 3am to get it done for Cars n Coffee. I patched up the splitter and straightened out the metal ductwork that mounts to it. The replacement fender was yellow, so I Plasti-dipped it black to keep from looking to sloppy for now. Eventually, I'll be patching the hood and doing a better job of paintwork on the areas that need it on the car....which are numerous.




Stopping for fuel on the way to C&C, I borrowed my Z06 to my uncle and his gf for the day.


Here's the car as of yesterday, I've been DD'ing it again to work the bugs out. Well that, and the damn thing pulls 33mpg on the interstate :thumbs::rock:


Next up: Spoiler build and Trackspec Motorsports Heat Extractor Install!

[monteboy84]

07-14-2014
Much to the chagrin of my girlfriend, I spent a fair amount of time with the racecar in my garage yesterday. After I saw them on here and developed a case of the 'gotta-haves', John at Trackspec Motorsports was very helpful in getting their louvered Heat Extractor panels out to me a few weeks ago, so I was happy to finally get them installed on the car.

As you've already seen, I cut the hood open before the BIR race in order to help relieve underhood pressure and help the radiator breathe. This opening was cut based on these extractor panels, but intentionally undersized to prevent error before the actual parts arrived. So, with the panels here, I measured them, laid out the correct opening size, and started cutting. Used carefully, a Sawzall works great for cutting fiberglass.


The picture above shows the reinforcement channel still in place, but with the depth of the louvers I had to remove it completely. With that done, I began more precise fitting of the center louver panel.


These were originally made primarily for racing hoods that tend to be more flat. My hood is original so it has a groove molded down the center that doesn't work just right with the flat panel, but some quick hand-forming of the back edge allowed it to fit nicely. John informed me that they have a simple solution in the works for this, so most people won't have to bend the panel like I did.


I added some more mounting holes and used 1/8" Cleco's to hold in place as I worked outward


I rolled the sides down a bit, again to fit the contour of this stock hood, and added Cleco's to secure it during test-fitting.


Center panel fully fitted, moving on to the sides...


They sent some really nice templates for the side cutouts. After playing around with placement, I finalized a location and traced the template shape with blue painters' tape.




Then I drilled some 1/4" holes in the corners, and started hacking away with my trusty Sawzall.




Then I laid out the other side to duplicate position




and ran a holesaw through the underside of the hood to provide ventilation without losing too much strength




After using the holesaw, I went after the cut edges of fiberglass with some 220 grit to soften them up, and put a quick coat of flat black on the exposed under-structure of the hood, sorry for not having pictures of this step.

The finished product looks fantastic, and the way it pulled sanding dust out of the hood when I got it on the road tells me they're working perfectly :thumbs:







:flag:

[monteboy84]

09-04-2014
Who doesn't like pictures of racecars?? :thumbs: Here are a few nice shots of my car from the World Racing League 15-hour race at MAM in Iowa. Photo credit goes to Alex Bellus for the awesome work

We finished 4th out of a ~25 car field. Should have finished 2nd or 3rd but there were a couple of issues that popped up and kept us off the podium. Being a fresh car, I'm still getting all of the bugs worked out and documenting fuel mileage so that we can do a better job planning pit stops and other strategy. As you can see, I built a wing for the car and I'm happy to say it made a HUGE difference in the feel of the car. Before, the aero was so imbalanced that the car felt loose and twitchy, always like the back end was going to step out in fast corners, it was a huge hindrance to speed because you couldn't be confident in the car. With the wing, it's planted, balanced, and stuck to the track, the car feels great and works awesome.

I won't be running the car again until heading down to TWS in December for the next WRL event. My to-do list includes a transmission swap after I put billet synchro keys, a steel 3-4 fork, and brass shift pads on the shift forks. This one started getting feisty late in the race and will no longer go into 1st gear. I'm also hoping that I have time to paint the car once I decide on what I want for a paint scheme...

[monteboy84]

10-09-2014
As I mentioned, the original transmission decided to get a bit snippy and not go into 1st anymore, as well as being picky about 2nd and 3rd as well. It seems that maybe it wasn't a fan of track abuse and heat :thumbs:

So, I took my spare trans apart and gave it a quick inspection before installing some reliability goodies:
- 3-4 synchro billet keys
- 3-4 Steel Shift Fork
- 1-2 and 3-4 Bronze Shift Fork Pads
- Drilled case with an AN6 port aimed at the input shaft for the trans cooler. The input shaft gets very hot on these due to fluid starvation, the idea here is to feed it fluid for cooling and in order to keep the bearing well-oiled.

The new trans looked great inside, I'm not sure how many miles were on it but it couldn't have been many.

Tailshaft housing pulled








I put everything from the mainshaft onto an aluminum tube as I took it off, this made reassembly much easier and foolproof than simply throwing everything into a tray.










Cooling port added






Skipped some steps, but here's the start of reassembly...




Greased all of the bearings before reassembly


Used 'Right Stuff' for case sealant. This is my first manual transmission teardown, so I had to take the case on and off a few times to get it right




Tada!


Prop shaft couplers were pretty ugly, better do them too...


I used OEM BMW guibos, the German made ones from Lemforder




The torque tube had some of the old coupler material in it

[monteboy84]

Getting ready to stuff it up into the car


Those who know what they're doing will recognize that at this point, I have the shift cover on backward so that later on my first test-drive, I won't have a functional reverse-lockout....Doh!




Cooler line hooked up to the new port


That's it for now, apparently I forgot to take more pictures, but the car is running and driving on the road again and the trans works perfect. Getting geared up to race at TWS in mid-December :rock:

[monteboy84]

12-17-2014
Well, I'm at my first day back at work following the big WRL race at TWS in College Station Texas. Unfortunately this track is not long for this world and will be tilled under in 2015 to make way for a high-end housing development, so that drove our decision to make the trek from MN and race there this winter. Truly awesome event, I think 54 cars in 3 classes took the green on Saturday, and close to the same took the green on Sunday.

The car worked awesome all weekend, it handled great and the motor ran perfect. We did have some issues with excessive fuel consumption, so we actually ran the whole course in 4th gear without any noticeable change to our lap times, while netting a 50% increase in minutes per tank. We still have some improvements to make in driver changes and fueling, as our driver change and fuel stops ran about 3 minutes as opposed to 2 minutes for the Spec Boxsters that we compete with most closely. We did have a couple minor issues on Saturday, where the splitter was pulled down in an off-track excursion, and a brake rotor cracked forcing us to change it out in a pit stop. Ultimately, we ended up finishing 7th overall, 4th in GP1 class on Saturday's 9 hour event, and 4th overall, 3rd in GP1 class on Sunday's 7-hour event. We got to meet Marc Sherrin and his team, great bunch of local Texas Corvette guys who run the Poorvette, an LT1-powered open-top C4. They had some issues on Saturday that kept them off-track most of Saturday, but got things turned around for Sunday and were able to race to a 4th place finish in GP1. Great bunch of guys and lots of fun to race with.

Here are some pictures from the event, I'll post some in-car video as well once I find time to edit it a bit. The Vette got a lot of love from everyone, including some closeted Corvette-loving Porsche drivers :D





























Here's most of the field, the 4 Spec Boxsters were actually ahead of the camera at this point, that silver Celica next to me is an awesome little car built by some guys who work at a Trans Am shop in Texas. It's got a 2JZ and ran awesome all weekend, great team of guys. As you can see, LOTS of variety in the field, tons of great racing throughout the weekend.

[monteboy84]

I have to say, in the most respectful way possible, that is probably the coolest looking "ugly" car I've ever seen. I bet it is tons of fun to drive, both track and street. Good job!

Thanks! I actually call her Ugly Betty, playing off my Z06 known as Black Betty. Hoping to get the wrap finished before we race at NCM in March, which will be another fun event. It really is a blast to drive, the car is very neutral and comfortable to drive at the limit, the reliability has been fantastic too which really helps make it fun. There's nothing worse than driving cross-country to race and fighting with issues all weekend, this car is all about staying on the track.

Here's a short in-car video from TWS, this was our fast lap of the weekend. Keep in mind that this was done in 4th gear around the whole track to save fuel, I'm confident that we could pick up a few seconds running all-out.
World Racing League TWS - Braunschweig Corvette Fast Lap - YouTube

[monteboy84]

02-27-2015
The car is getting an updated look, here's a crappy teaser pic from my phone.

[monteboy84]

03-02-2015
Thanks guys!

73Corvette, what can I say, I'm blushing! I appreciate the kind words. Racing has been the one thing that really brought my dad and I together over the last 10-12 years I started racing with him and my brother in high school but went on the road racing with some friends of mine, it was a lot of fun but I was spending less and less time with my family which really bugged me. So, I pulled out of that and started doing endurance racing with dad a couple years ago, that's morphed into what you see here. My grandpa doesn't make it out too often since most of the races are out of state, but he enjoys coming to the one MN race that we usually run. It's a blast all around, fun being able to compete and put the skills to use that they taught me over the years.

More pics of the new livery below. I still need to get the spoiler fixed and bolted on but that's easier to do at home versus the bigger ticket items that need done at the shop. Anywho, here it is with the splitter re-mounted and the wrap finished, just missing contingency stickers and all that. The old splitter mounts were less than spectacular so I made a one-piece bar that sits behind the bumper cover. It has tubes that can pivot upward so if it bottoms out it won't damage the vertical strut tubes.

The new mount points also allow me to run Z06 screens without having to hack them up for the tubes to run through

[monteboy84]

Here are some pictures from the weekend at NCM Motorsports Park, I don't have time to caption or organize them now but will run back through them later, hopefully tonight.

[monteboy84]

05-14-2015
Some cool pictures from our recent event at BIR. It was a solid weekend, we won on Saturday and came in 2nd in class, 3rd overall Sunday after a few off-track adventures in the rain. Overall the car is still working great and I/we are having a blast with it. Every driver that I've put in the car (8 now?) has loved it. Our fast time for the weekend was a 1:46.266 on Sunday, tied exactly with that of a full aero '99 M3 piloted by Chris Orr. A great weekend all-around, lots of fun. Car needs a fender and some work on the front fascia, but for now I'm tending to the lawn and some work on the house.

[Centerforce]

About halfway through the build's first page on here, I thought I'd figured out which car this was (and I was right). Great build and love the engine choice for that particular race series, too. It wears the track grime at NCM nicely, if I do say so myself.

[brawls43]

Such a great build. Nice work Matt