Used a mechanics stethoscope on the fuel injectors yesterday: all except #3 made a distinct tap-tap-tap. #3 made a very faint tap-tap overlaid with a whoosh-whoosh. It sounds very different, so today I will start on replacement.
My Chump Car 1989 Supra, #32
- Thread starter SiberianDVM
- Start date
1 hour job turned into 2 hour job when I forgot to hook up the 1/4" water line going to the bottom of the ICS valve, but finally: it works!!! Replacement of the #3 injector fixed the misfire & made it idle smoother. I can't wait to get it into the next race.
Beware of remanufactured injectors.
Beware of remanufactured injectors.
I didn't do the engine assembly following the long block rebuild, but I did buy the remanufactured fuel injectors. They all tested normal then, but this one apparently started failing right after we did the engine break-in runs.
Good deal. By the way, an injector balance test is quick and likely would have pinpointed this fast. Pull each injector clip one by one and check the idle drop. Need to be fast as the ECU will correct the idle speed back to spec. Can also be done by monitoring fuel rail pressure drop if you have the test gear.
Brakes:
We are still using the stock single piston calipers (NAPA remans), stock vented rotors (new NAPAs), stock master, ABS system, with Motul 660 RBF and Porterfield R4 racing pads. The system seems to work decently,with no rear end lockup, but it could stand some improvement as there is some ABS pulsing on heavy braking. Of course, CCWS changed the rules right after I stocked up on stock calipers.
Right now we are wearing out a set of front brake pads about every 14-18 hours and the rears are lasting 2-3 times as long. Front rotors are showing moderate wear and I am having them resurfaced every 2 races. So far the rear rotors look almost new after over 30 hours of racing.
Is heavy front and light rear wear normal on this car? Should I replace or clean the proportioning valve? Or just use a more aggressive rear pad? Should I look at adding some front brake cooling/ducting?
We are still using the stock single piston calipers (NAPA remans), stock vented rotors (new NAPAs), stock master, ABS system, with Motul 660 RBF and Porterfield R4 racing pads. The system seems to work decently,with no rear end lockup, but it could stand some improvement as there is some ABS pulsing on heavy braking. Of course, CCWS changed the rules right after I stocked up on stock calipers.
Right now we are wearing out a set of front brake pads about every 14-18 hours and the rears are lasting 2-3 times as long. Front rotors are showing moderate wear and I am having them resurfaced every 2 races. So far the rear rotors look almost new after over 30 hours of racing.
Is heavy front and light rear wear normal on this car? Should I replace or clean the proportioning valve? Or just use a more aggressive rear pad? Should I look at adding some front brake cooling/ducting?
Based on street driving its at least 2:1 longer wear on the rears.
You could look at using dual piston Previa calipers as they are a direct fit. Unclear if it would buy you anything though. I think you really need a bigger disk to make a difference.
previa
caliper assy: 47730-28200
pads 04491-28351 04665-28170
You could look at using dual piston Previa calipers as they are a direct fit. Unclear if it would buy you anything though. I think you really need a bigger disk to make a difference.
previa
caliper assy: 47730-28200
pads 04491-28351 04665-28170
Thanks. Probably even more than 2:1 in racing, so it's probably "normal" for this car. I may take the proportioning valve out and make sure it's not full of gunk and try to route some cooling to the front brakes.
I made it back from Daytona, mostly in 1 piece. This was our 3rd race, and the 1st that we DNF.
Our transponder failed before start; had to rent one and zip-tie it in place; lost 3 laps.
Heat was our enemy. Oil temp was over 260°F most of the day, except when it was raining. After about 4 hours, the clutch failed. Car stalled coming into pits and would not restart due to clutch interlock. With no P/S, I broke the weld on the steering wheel quick release. Once we got the car pushed to the garage, with a Vicegrip on the steering column, I found a bolt on the clutch pedal assembly had backed out and fallen into the floorboard, so I fixed that, then had to borrow a welder and fix the steering wheel. 30 laps lost.
Nobody wanted to drive the car with a suspect steering wheel, so I got in and did 30 minutes before the monsoon flooded the track. Nothing like going through the high bank at 125 mph at not being able to see anything due to the rooster-tails. Flat areas got flooded, cars were wrecking everywhere, so they red flagged it for a while.
The other drivers got their nuts back, and one hopped in when the red changed to yellow, then green. We did a few more hours (car ran good and was competitive when it wasn't broke), then the brakes went away. We took it to garage to change the front pads, and found that another bolt had fallen out, this time one holding on the front right brake caliper. Another 20 laps lost.
We fixed all that, then saw an oil leak and heard a strange noise coming from somewhere underneath. Jacked it up and looked/listened but couldn't find it, so we figured all our luck was used up, so we threw in the towel. Another 30 laps lost.
Due to our transponder difficulties , we're not sure exactly where we finished, but we think it was something like 64th of 108.
Frick.
Our transponder failed before start; had to rent one and zip-tie it in place; lost 3 laps.
Heat was our enemy. Oil temp was over 260°F most of the day, except when it was raining. After about 4 hours, the clutch failed. Car stalled coming into pits and would not restart due to clutch interlock. With no P/S, I broke the weld on the steering wheel quick release. Once we got the car pushed to the garage, with a Vicegrip on the steering column, I found a bolt on the clutch pedal assembly had backed out and fallen into the floorboard, so I fixed that, then had to borrow a welder and fix the steering wheel. 30 laps lost.
Nobody wanted to drive the car with a suspect steering wheel, so I got in and did 30 minutes before the monsoon flooded the track. Nothing like going through the high bank at 125 mph at not being able to see anything due to the rooster-tails. Flat areas got flooded, cars were wrecking everywhere, so they red flagged it for a while.
The other drivers got their nuts back, and one hopped in when the red changed to yellow, then green. We did a few more hours (car ran good and was competitive when it wasn't broke), then the brakes went away. We took it to garage to change the front pads, and found that another bolt had fallen out, this time one holding on the front right brake caliper. Another 20 laps lost.
We fixed all that, then saw an oil leak and heard a strange noise coming from somewhere underneath. Jacked it up and looked/listened but couldn't find it, so we figured all our luck was used up, so we threw in the towel. Another 30 laps lost.
Due to our transponder difficulties , we're not sure exactly where we finished, but we think it was something like 64th of 108.
Frick.
Just got back Monday from our 4th ChumpCar race: The Slightly More Than 12 Hours of Sebring; 14 hours to be exact, that was held on Saturday, Sep 26. I had plenty of time to get the car ready since the last race, so I had no excuses. This time we went with a team of 4, which was about the minimum that I would want for a 14 hour race. It's not the driving time that gets you, it's all the prepping, hauling, unpacking, setting up, repairing, fueling, tearing down, repacking, hauling home, and unpacking and unloading.
We all got there Friday, and set up in Pit 61 and Garage 61, right under the 1958 Ferrari banner, very close to pit out. Got the car in the garage, up on stands, and did the final checks (found 2 missing shock tower nuts!!) and brake bleeds. Also got the canopy set up along the pit wall, and all the gear laid out.
So, naturally, we had a monsoon. The next morning everything was soaking wet. It all dried eventually, but what a mess. Race day dawned clear, but was partly cloudy and steamy hot all day. During the time since the last race I had made some hood vents and altered the water thermostat a bit to try to keep the engine cooler, and it helped about 20° F for both the oil and water temps. The car would idle much better when coming in off a run and never stalled like it would before.
For this race I decided to try a new (to us) front brake pad compound, the Raybestos ST43 and a new set of Frozen Rotors front rotors. They worked well throughout the race. Still running Bridgestone RE-11 tires: the rears are still going strong after 3 races, the fronts decided to get washy about 12 hours into the race, but they already had about 8 hours on them from a previous race. Due to liberal use of Loctite, no brakes fell off this time.
Mark was 1st out at 0900. We wanted to try to minimize our pit stops by having 1:55 drive stints and 5 minute fuel stops/driver changes. Due to our excess points, we had 5 penalty laps, so we started in 92nd position, out of 93 starters. Six cars did not start the race. Mark was instructed to drive conservatively and to save the car, avoiding mayhem. During this 1st stint, he ran mostly 2:55 laps, with one at 2:52, and we moved to 80th place.
Jimmy was up next, from 1100 to 1300. Same instructions: save the car. He did a great job, with the car running smoothly, and ran his best lap of 2:50. The car was taking about 13-14 gallons of fuel after each stint. Now we were up to 66th.
Steve was next to go about 1300. Sometime during his run there was a red flag due to another car hitting a wall, and then the driver getting out of the car and collapsing before being taken away by ambulance. The cars were all stopped out on the track for a while, then brought to pit lane while things were sorted out. With the engine turned off, it was very hot inside even with Coolshirts (we need some forced air blowing in the drivers face), so the drivers were permitted to get out and drink some water. They went back out for about 15 minutes of yellow and green before Steve came in. Sometime during this mess, Steve got a 1 minute stop and go penalty for passing under the yellow. WTF? EVERYBODY passes under the yellow!!! We were now up to 52nd, at about 1500 (3PM).
My turn. I was a LOT less nervous than this time 2 years ago, when Sebring was my first ever WTW race, in a rented seat in Miata. That time I almost puked before getting in the car. Still, I had the butterflies. But I built this car, and it is a tank. It took me 30 minutes to get the hang of the car and the track, then I started feeling better and actually started fighting for positions. Sebring has 3 long straights followed by difficult turns, and I was getting the old girl up to 105-115 mph at times. The brakes felt good, but the front tires were only so-so. T5 was slick, and I was not the only car having trouble there: I drove off line to the right through the grass twice to miss cars that were spinning in front of me. About 45 minutes into my run, it started raining in T7, T8, & T9. I knew it would get really slick going into the hard braking zone at T7, so I started easing up going through T6. Other drivers did too, but there are always the 10% who don't get the memo. Over the next 30 minutes the carnage was heavy, and I spent most of my remaining drive time under FCY. Car was running good; ended my stint in 46th place at 1700 (5PM). My best time was a 2:58. We added 1 quart of oil.
I have no idea how many exactly, but cars are being loaded onto trailers and going home. Some are wrecked, some are just broken down. The late 70s Camaro pitted next to us has gone home after a failed transmission. After our DNF at Daytona I want to finish this one badly, and I have chewed at least 10 pieces of Nicorette gum. I would kill for a cigarette. While walking to the men's room, I stopped to talk to a girl sitting and smoking a cig. The secondhand smoke was fabulous.
Jimmy was back in the car from 1700 to 1900. The rain had stopped but was predicted to come back. Heavy clouds overhead made it seem darker than it was. Some cars were starting to turn on their headlights. Jimmy starts to pick up the pace and runs a 2:46, then a 2:40. He radios in that he is in a clear section of track with no traffic, so he is able to do his thing. Temps are 210° water and 230° oil so I tell him to watch them and to back off if they go any higher. At 1830 Jimmy radios in that he has to pit, as the car has stumbled coming through T17 and the gas gauge is on E and the reserve light is on. We scramble to put on our Nomex and helmets so we can fuel. Did we short fuel last time? We put in another 5 gallons and send him back out to finish his stint. That cost us 5 minutes and 2 positions. We are now in 38th, down from 36th.
Mark is back in from 1900 to 2100. He will be racing in full darkness, but he has 8000 lumens of LED headlights and doesn't complain, at least until about 2000 when he says the front tires are going away. I had checked the pressures and the tread and all looked good, but they have a lot of racing hours on them now. We tell him to drive to the condition of the car. He sets his best lap of the race, and then radios in that he is low on fuel!! So we bring him in and give the car another 10 gallons and lose another 5 minutes and 2 positions. We are in 28th position.
Steve will finish the race from 2100 to 2300. One stint is enough for me these days. We add another quart of oil. Check the tire pressures and let 2 psi out of the fronts. He takes off and I chew my finger nails. Steve is hauling ass. After 10 laps we are up to 24th. After 20 laps, still 24th. Then Steve radios in that he thinks a headlight fell off the car.
The car definitely looked weird coming down the front straight, so we tell him to pit next lap and I go looking for tools. When he comes in, the left headlight is dangling by the cord, but still shining! I duck taped it back in, as the retaining ring is somewhere out on Sebring, and he is gone in 2 minutes. Still 24th position.
At 2245, Steve radios in that he is low on gas and must pit. The car is sputtering on T17. I know we have been getting full fills, because I have been doing it. So in we come with 15 minutes to go. Since the fuel stop is a minimum of 5 minutes, we put in 10 gallons. This extra stop drops us to 25th.
And that's where we finished. At Sebring, they allow the crews to come out to the race fence on the last lap to cheer them in. If you ever get a chance to get that close to race cars at WOT, any race cars, even tired old race cars, then DO IT. It gave me goose bumps to see and hear our old girl go by at 110+ mph, that 3" open pipe sounding glorious.
Now if i can just figure out a way to get another 300 pounds out of this fat bitch.................
We all got there Friday, and set up in Pit 61 and Garage 61, right under the 1958 Ferrari banner, very close to pit out. Got the car in the garage, up on stands, and did the final checks (found 2 missing shock tower nuts!!) and brake bleeds. Also got the canopy set up along the pit wall, and all the gear laid out.
So, naturally, we had a monsoon. The next morning everything was soaking wet. It all dried eventually, but what a mess. Race day dawned clear, but was partly cloudy and steamy hot all day. During the time since the last race I had made some hood vents and altered the water thermostat a bit to try to keep the engine cooler, and it helped about 20° F for both the oil and water temps. The car would idle much better when coming in off a run and never stalled like it would before.
For this race I decided to try a new (to us) front brake pad compound, the Raybestos ST43 and a new set of Frozen Rotors front rotors. They worked well throughout the race. Still running Bridgestone RE-11 tires: the rears are still going strong after 3 races, the fronts decided to get washy about 12 hours into the race, but they already had about 8 hours on them from a previous race. Due to liberal use of Loctite, no brakes fell off this time.
Mark was 1st out at 0900. We wanted to try to minimize our pit stops by having 1:55 drive stints and 5 minute fuel stops/driver changes. Due to our excess points, we had 5 penalty laps, so we started in 92nd position, out of 93 starters. Six cars did not start the race. Mark was instructed to drive conservatively and to save the car, avoiding mayhem. During this 1st stint, he ran mostly 2:55 laps, with one at 2:52, and we moved to 80th place.
Jimmy was up next, from 1100 to 1300. Same instructions: save the car. He did a great job, with the car running smoothly, and ran his best lap of 2:50. The car was taking about 13-14 gallons of fuel after each stint. Now we were up to 66th.
Steve was next to go about 1300. Sometime during his run there was a red flag due to another car hitting a wall, and then the driver getting out of the car and collapsing before being taken away by ambulance. The cars were all stopped out on the track for a while, then brought to pit lane while things were sorted out. With the engine turned off, it was very hot inside even with Coolshirts (we need some forced air blowing in the drivers face), so the drivers were permitted to get out and drink some water. They went back out for about 15 minutes of yellow and green before Steve came in. Sometime during this mess, Steve got a 1 minute stop and go penalty for passing under the yellow. WTF? EVERYBODY passes under the yellow!!! We were now up to 52nd, at about 1500 (3PM).
My turn. I was a LOT less nervous than this time 2 years ago, when Sebring was my first ever WTW race, in a rented seat in Miata. That time I almost puked before getting in the car. Still, I had the butterflies. But I built this car, and it is a tank. It took me 30 minutes to get the hang of the car and the track, then I started feeling better and actually started fighting for positions. Sebring has 3 long straights followed by difficult turns, and I was getting the old girl up to 105-115 mph at times. The brakes felt good, but the front tires were only so-so. T5 was slick, and I was not the only car having trouble there: I drove off line to the right through the grass twice to miss cars that were spinning in front of me. About 45 minutes into my run, it started raining in T7, T8, & T9. I knew it would get really slick going into the hard braking zone at T7, so I started easing up going through T6. Other drivers did too, but there are always the 10% who don't get the memo. Over the next 30 minutes the carnage was heavy, and I spent most of my remaining drive time under FCY. Car was running good; ended my stint in 46th place at 1700 (5PM). My best time was a 2:58. We added 1 quart of oil.
I have no idea how many exactly, but cars are being loaded onto trailers and going home. Some are wrecked, some are just broken down. The late 70s Camaro pitted next to us has gone home after a failed transmission. After our DNF at Daytona I want to finish this one badly, and I have chewed at least 10 pieces of Nicorette gum. I would kill for a cigarette. While walking to the men's room, I stopped to talk to a girl sitting and smoking a cig. The secondhand smoke was fabulous.
Jimmy was back in the car from 1700 to 1900. The rain had stopped but was predicted to come back. Heavy clouds overhead made it seem darker than it was. Some cars were starting to turn on their headlights. Jimmy starts to pick up the pace and runs a 2:46, then a 2:40. He radios in that he is in a clear section of track with no traffic, so he is able to do his thing. Temps are 210° water and 230° oil so I tell him to watch them and to back off if they go any higher. At 1830 Jimmy radios in that he has to pit, as the car has stumbled coming through T17 and the gas gauge is on E and the reserve light is on. We scramble to put on our Nomex and helmets so we can fuel. Did we short fuel last time? We put in another 5 gallons and send him back out to finish his stint. That cost us 5 minutes and 2 positions. We are now in 38th, down from 36th.
Mark is back in from 1900 to 2100. He will be racing in full darkness, but he has 8000 lumens of LED headlights and doesn't complain, at least until about 2000 when he says the front tires are going away. I had checked the pressures and the tread and all looked good, but they have a lot of racing hours on them now. We tell him to drive to the condition of the car. He sets his best lap of the race, and then radios in that he is low on fuel!! So we bring him in and give the car another 10 gallons and lose another 5 minutes and 2 positions. We are in 28th position.
Steve will finish the race from 2100 to 2300. One stint is enough for me these days. We add another quart of oil. Check the tire pressures and let 2 psi out of the fronts. He takes off and I chew my finger nails. Steve is hauling ass. After 10 laps we are up to 24th. After 20 laps, still 24th. Then Steve radios in that he thinks a headlight fell off the car.
The car definitely looked weird coming down the front straight, so we tell him to pit next lap and I go looking for tools. When he comes in, the left headlight is dangling by the cord, but still shining! I duck taped it back in, as the retaining ring is somewhere out on Sebring, and he is gone in 2 minutes. Still 24th position.
At 2245, Steve radios in that he is low on gas and must pit. The car is sputtering on T17. I know we have been getting full fills, because I have been doing it. So in we come with 15 minutes to go. Since the fuel stop is a minimum of 5 minutes, we put in 10 gallons. This extra stop drops us to 25th.
And that's where we finished. At Sebring, they allow the crews to come out to the race fence on the last lap to cheer them in. If you ever get a chance to get that close to race cars at WOT, any race cars, even tired old race cars, then DO IT. It gave me goose bumps to see and hear our old girl go by at 110+ mph, that 3" open pipe sounding glorious.
Now if i can just figure out a way to get another 300 pounds out of this fat bitch.................
What a fantastic read! I'd love to do something like this one day. Any updates? We need more pics too!
I loved the read! Any interior pictures? Theres tons of way to reduce weight. You can get that car under 3000lbs easy.
Subscribed. Are you still competing? I may be joining you in the series in the next few years God willing.
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