C4 Race Car Build - roadrace, endurance
#81
As somebody who has raced with Chump/Champ, in a Corvette, I have an idea of how well Corvettes run. They are definitely not equipped to go battle with the Miata/E36's that run.
Last edited by ChumpVette; 12-31-2018 at 12:53 PM.
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Mostmint (12-31-2018)
#82
interesting. i have zero experience with this and your comment, which is obviously based in experience, begs the question, can u give examples of the weakpoints in the c4 vs a miata or e36 that would fail or whatever?
Im genuinely intrigued and id like to learn. what makes them more robust or durable in the racing world
#83
Le Mans Master
interesting. i have zero experience with this and your comment, which is obviously based in experience, begs the question, can u give examples of the weakpoints in the c4 vs a miata or e36 that would fail or whatever?
Im genuinely intrigued and id like to learn. what makes them more robust or durable in the racing world
#84
Advanced
interesting. i have zero experience with this and your comment, which is obviously based in experience, begs the question, can u give examples of the weakpoints in the c4 vs a miata or e36 that would fail or whatever?
Im genuinely intrigued and id like to learn. what makes them more robust or durable in the racing world
Im genuinely intrigued and id like to learn. what makes them more robust or durable in the racing world
In the 11,000+ miles I have run with my Saturn SC I have routinely finished ahead of the majority of BMW and Mazda products - with overall podium finishes and class wins in three of my past five races. The key element here is not just single lap speed but reliability. Believe me there was a lot of engineering and preparation required to make a Saturn run near the front.
So to somewhat address your question I don't believe the E30, E36 (excluding M) or Miata are better performing cars for single lap performance otherwise I would be building one. In fact the SCCA banned C4s from showroom stock in the late 1980's creating the Corvette World Challenge cars. However these other vehicles have a lot of out of the box performance which attract a lot of teams to use them as a platform. There have been precious few Chevy V8s that finish these endurance races without issue, which is not a problem for most of these others. Also there is a cost factor. The Vette has a bigger engine and is heavier so it will eat more gas, tires, brakes.
Like you I am very curious the practical problems with running these in endurance road racing.
#85
Safety Car
Kubs here on the forum has a 1990 set up for road racing, I am not sure what class he runs in.
Mostmint, Kubs lives over in Portage Lakes.
Mostmint, Kubs lives over in Portage Lakes.
#86
What almost all of you forget, there are different series. Champ/Chump is set up for 7-24 hours of racing. What somebody has for track day sessions for 30 minutes or SCCA for 45-50 minutes does not equal success for 3 hours or up to 24.
Corvettes & Camaros have not done well in the series or any of the others due to a host of issues.
1) Perceived value is to high. There are limits on what you can do in these series before you are bumped up a class or out of the league altogether. A Corvette has a higher entry value according to their rules, and as such, you don't have enough dollars left to add for parts to keep you on the track for the entire race. (Series is supposed to be 500, Corvette starts out above that and a Miata, E36 and almost every other vehicle that runs starts below that. So they automatically can spend 2-300 for better shocks, bushings, radiators, etc)
2) V8's consume a ton of fuel. Just because you can go fast doesn't mean you will make up that time on a pit stop. A corvette with a stock fuel tank will not go 2 hours (max stint length) unless you add a fuel cell. You start adding a fuel cell, you can only add 2 gallons (If I remember correctly), so max capacity is now 22 gallons. That might get you to 2 hours, but probably not. The miata and E36 with smaller engines consume less fuel over the 2 hour stint. Spend less time in the pits fueling.
3) Heat control. This is the enemy of [b}ANY[/b] endurance team. V8 will require bigger rad. The factory radiator and the rinky dink oil cooler will not cover it. You need a power steering cooler, you need brake cooling, you might even consider a trans and diff cooler. Remember a V8 creates a lot of heat in racing. And also remember, you've got no money to add these things if you want to "race" in their class.
4) Oil starvation, oil pan is not suitable, need a Canton or a Accusump, remember, it's value add and you can't spend the money.
5) Tires. Popular sizes for these endurance racers are 15/16" tires. Narrow tires. 255/55/16 or any 17 or 18 didn't exist until recently in the popular tires built for these classes. "Direzza's". V8's also love to chew up the rear tires. And since they are nose heavy, they love to eat up the fronts too.
There are more points, but these are the highlights.
So Matthew, I would love to see you build a crapcan C4 and come out and try to see how well you do, "fitting" into the rules of budget racing. You can build a C4 race car, just don't expect it to be competitive in this world of endurance racing.
Corvettes & Camaros have not done well in the series or any of the others due to a host of issues.
1) Perceived value is to high. There are limits on what you can do in these series before you are bumped up a class or out of the league altogether. A Corvette has a higher entry value according to their rules, and as such, you don't have enough dollars left to add for parts to keep you on the track for the entire race. (Series is supposed to be 500, Corvette starts out above that and a Miata, E36 and almost every other vehicle that runs starts below that. So they automatically can spend 2-300 for better shocks, bushings, radiators, etc)
2) V8's consume a ton of fuel. Just because you can go fast doesn't mean you will make up that time on a pit stop. A corvette with a stock fuel tank will not go 2 hours (max stint length) unless you add a fuel cell. You start adding a fuel cell, you can only add 2 gallons (If I remember correctly), so max capacity is now 22 gallons. That might get you to 2 hours, but probably not. The miata and E36 with smaller engines consume less fuel over the 2 hour stint. Spend less time in the pits fueling.
3) Heat control. This is the enemy of [b}ANY[/b] endurance team. V8 will require bigger rad. The factory radiator and the rinky dink oil cooler will not cover it. You need a power steering cooler, you need brake cooling, you might even consider a trans and diff cooler. Remember a V8 creates a lot of heat in racing. And also remember, you've got no money to add these things if you want to "race" in their class.
4) Oil starvation, oil pan is not suitable, need a Canton or a Accusump, remember, it's value add and you can't spend the money.
5) Tires. Popular sizes for these endurance racers are 15/16" tires. Narrow tires. 255/55/16 or any 17 or 18 didn't exist until recently in the popular tires built for these classes. "Direzza's". V8's also love to chew up the rear tires. And since they are nose heavy, they love to eat up the fronts too.
There are more points, but these are the highlights.
So Matthew, I would love to see you build a crapcan C4 and come out and try to see how well you do, "fitting" into the rules of budget racing. You can build a C4 race car, just don't expect it to be competitive in this world of endurance racing.
#87
Le Mans Master
So again, they've made it so that truly fast cars probably can't compete, and that's understandable. If they let the C4 compete on a level playing field it would dominate everything else that's even close in actual cost. They want the series to be a lot slower than that, and there are good reasons behind that desire. Likewise, when Grassroots Motorsports snuck a turbo onto their Miata, the series took a dim view of that. I was just pointing out that how a car fares in a class like Chumpcar is not an indicator of its actual speed and potential, and that nobody should mistake a C4 as being slower than an older Miata or E36.
#88
Team Owner
Pro Mechanic
I wonder how the V8 would do on fuel if you kept it in a higher gear. Sometimes 100% power (high fuel consumption) only makes you very marginally faster (if at all). I wonder what would happen if you stuck it in a high gear and drove it like a "momentum car" (a miata). This would also lower the burden on the oil pan, oil temps, and cooling system.
.
Last edited by Tom400CFI; 12-31-2018 at 07:19 PM.
#89
Advanced
What almost all of you forget, there are different series. Champ/Chump is set up for 7-24 hours of racing. What somebody has for track day sessions for 30 minutes or SCCA for 45-50 minutes does not equal success for 3 hours or up to 24.
Corvettes & Camaros have not done well in the series or any of the others due to a host of issues.
1) Perceived value is to high. There are limits on what you can do in these series before you are bumped up a class or out of the league altogether. A Corvette has a higher entry value according to their rules, and as such, you don't have enough dollars left to add for parts to keep you on the track for the entire race. (Series is supposed to be 500, Corvette starts out above that and a Miata, E36 and almost every other vehicle that runs starts below that. So they automatically can spend 2-300 for better shocks, bushings, radiators, etc)
2) V8's consume a ton of fuel. Just because you can go fast doesn't mean you will make up that time on a pit stop. A corvette with a stock fuel tank will not go 2 hours (max stint length) unless you add a fuel cell. You start adding a fuel cell, you can only add 2 gallons (If I remember correctly), so max capacity is now 22 gallons. That might get you to 2 hours, but probably not. The miata and E36 with smaller engines consume less fuel over the 2 hour stint. Spend less time in the pits fueling.
3) Heat control. This is the enemy of [b}ANY endurance team. V8 will require bigger rad. The factory radiator and the rinky dink oil cooler will not cover it. You need a power steering cooler, you need brake cooling, you might even consider a trans and diff cooler. Remember a V8 creates a lot of heat in racing. And also remember, you've got no money to add these things if you want to "race" in their class.
4) Oil starvation, oil pan is not suitable, need a Canton or a Accusump, remember, it's value add and you can't spend the money.
5) Tires. Popular sizes for these endurance racers are 15/16" tires. Narrow tires. 255/55/16 or any 17 or 18 didn't exist until recently in the popular tires built for these classes. "Direzza's". V8's also love to chew up the rear tires. And since they are nose heavy, they love to eat up the fronts too.
Corvettes & Camaros have not done well in the series or any of the others due to a host of issues.
1) Perceived value is to high. There are limits on what you can do in these series before you are bumped up a class or out of the league altogether. A Corvette has a higher entry value according to their rules, and as such, you don't have enough dollars left to add for parts to keep you on the track for the entire race. (Series is supposed to be 500, Corvette starts out above that and a Miata, E36 and almost every other vehicle that runs starts below that. So they automatically can spend 2-300 for better shocks, bushings, radiators, etc)
2) V8's consume a ton of fuel. Just because you can go fast doesn't mean you will make up that time on a pit stop. A corvette with a stock fuel tank will not go 2 hours (max stint length) unless you add a fuel cell. You start adding a fuel cell, you can only add 2 gallons (If I remember correctly), so max capacity is now 22 gallons. That might get you to 2 hours, but probably not. The miata and E36 with smaller engines consume less fuel over the 2 hour stint. Spend less time in the pits fueling.
3) Heat control. This is the enemy of [b}ANY endurance team. V8 will require bigger rad. The factory radiator and the rinky dink oil cooler will not cover it. You need a power steering cooler, you need brake cooling, you might even consider a trans and diff cooler. Remember a V8 creates a lot of heat in racing. And also remember, you've got no money to add these things if you want to "race" in their class.
4) Oil starvation, oil pan is not suitable, need a Canton or a Accusump, remember, it's value add and you can't spend the money.
5) Tires. Popular sizes for these endurance racers are 15/16" tires. Narrow tires. 255/55/16 or any 17 or 18 didn't exist until recently in the popular tires built for these classes. "Direzza's". V8's also love to chew up the rear tires. And since they are nose heavy, they love to eat up the fronts too.
I want to add that the parameters that created point #1 are changing some. For the past few years the C4 started at 530 points and therefore with penalty laps (500 is max with no penalty laps). For 2019 the base value is 450 points. If you choose to run automatic that is a 75 point deduction so you can start at 375 points. The point may still be valid I am not sure yet but now there is some room to move.
For example Accusump is now 10 points, non-OE external oil cooler is 20 points, non-OE pan is 25 points, aluminum non-OE radiator under $300 cost is 10 pts. These are options.
Last edited by Mostmint; 12-31-2018 at 07:22 PM.
#90
Thanks for sharing your experiences with the platform. I don't know about everyone else but I have over 11,000 miles of road racing and I agree there is a HUGE difference between a heat race or a 20 minute HPDE session and a real endurance race.
I want to add that the parameters that created point #1 are changing some. For the past few years the C4 started at 530 points and therefore with penalty laps (500 is max with no penalty laps). For 2019 the base value is 450 points. If you choose to run automatic that is a 75 point deduction so you can start at 375 points. The point may still be valid I am not sure yet but now there is some room to move.
For example Accusump is now 10 points, non-OE external oil cooler is 20 points, non-OE pan is 25 points, aluminum non-OE radiator under $300 cost is 10 pts. These are options.
I want to add that the parameters that created point #1 are changing some. For the past few years the C4 started at 530 points and therefore with penalty laps (500 is max with no penalty laps). For 2019 the base value is 450 points. If you choose to run automatic that is a 75 point deduction so you can start at 375 points. The point may still be valid I am not sure yet but now there is some room to move.
For example Accusump is now 10 points, non-OE external oil cooler is 20 points, non-OE pan is 25 points, aluminum non-OE radiator under $300 cost is 10 pts. These are options.
I got marginalized out of Chump with their rules, mainly with the swap rules. I got tired of playing the catch up game with rule changes and finally said "F them". There are other series that want my money and don't make me jump through hoops.
By the way, here is a quote from Smith on the C4.
Success... we finally did it, we finished a whole event. It took 4 races and 3 motors but finally the Corvette took the checkered flag. It was a long weekend with only 2 of us racing an pitting but we did it. Now back to work to fix the newly discovered issues like fuel system (we were only using 10gal of our 20gal tank) and repair some damaged wheels.
#91
Team Owner
Pro Mechanic
I was thinking about the fuel/RPM thing more. The 'Vette team has cited the large displacement/lower RPM as a fuel saving benefit in the LeMans car. It seems like you could exploit that characteristic too...but it would take discipline.
#92
Advanced
The new VPI table is here https://champcar.org/mainweb/pdf/VPITable2019v3.pdf and I presume the main table will be updated shortly since 2019 is around the corner.
#93
Advanced
#94
Advanced
Congrats on the stout 2:17 lap time and getting a good run in the ChampCar race at Daytona last weekend.
Was sad to see the car stopped around 11 hours - hoping it is something fixable!
Was sad to see the car stopped around 11 hours - hoping it is something fixable!
#95
any videos?
#96
Instructor
Thread Starter
Thanks. We had a good run bud had to stopp when the clutch MC died on us. The car is getting there in Dec we finished the Double 7 at Sebring with just 2 drivers.
#97
or pics??
#98
Instructor
Thread Starter
This is what we do. With the FAST we can and do adjust the rev limiter and also can pull a little timing out to be safe. We can do it at any pit stop, so if a driver is abusing the car we can control it. Just lessons learned after going through 3 motors.
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confab (04-16-2019)
#100
Melting Slicks
All that stuff you pulled off if I were you ... you can sell on the forum C4 parts page and the proceeds you can use to buy things for your racecar.
I noticed that you had a 35th anniversary emblem on your car. That too is worth money ... it also means it's an 1988.
I noticed that you had a 35th anniversary emblem on your car. That too is worth money ... it also means it's an 1988.
Last edited by 3D-Aircrew; 04-16-2019 at 10:35 AM.