C5 Corvette Track Journey

nsogiba said:

In reply to theruleslawyer :

I had the same issue with the exhaust bolts on my C5. Just ended up doing headers from Huron Speed (don't know if they still offer that system). Maybe just torch/drill out those studs and replace? I get not wanting to throw more money at the problem. 

Yah. Sunday I broke out the torch and was able to get 2/3 studs replaced on each header. I tried drilling the remaining ones after they sheared flat. No luck. The angle I could get the drill in was weird. If I'm taking the headers out it will be for new ones. Its sealed for now. I think I'll probably get a set of speed engineering headers. They seem the go-to cheap header right now. There are incredibly cheap ebay headers, but reports are that fitment is a bit of a fight. another option is the newer 01+ headers. Supposedly they are good for 10hp over the 99 headers. Plus they are direct fit rather than requiring a lot of work downstream. And cheap. really cheap.

Also did the brake flush with SRF. I put 2l through. Pedal is a little squishier than I'd like. I'll have to try another bleed again. The wilwoods appear to have a valved bleeders which makes the motive power bleeder not push very much fluid. I pumped the pedal to speed up the rear, but I may have sucked air in?

If you're going to pull manifolds altogether, just do longtubes. I had a buddy with a C5 coupe with no exhaust mods - we went for a ride in my C5 FRC with longtubes and he said the acceleration delta was "significant". 

Buttoning things up this weekend.

• Got the AC working. Installed a new exterior temp sensor and recharged the system. the low pressure fill valve seems to be leaking, but that's a problem for future me. Resting the bottle on the header really helps counter the bottle freezing up.  It blows cold now
• Hood back on
• Degreased the engine to clean up any remaining goop from all the installs.
• Fixed a parking brake spring that had come loose. It was dragging on a test drive
• Oil changed
• Tightened the oil distribution block
• Checked fluid levels
• Setup Catalyst
• setup camera
• setup remote for camera
• Attempted to bleed the brakes again. The motive bleeder decided to leak this time. $40 of SRF all over the floor while attempting to get it all setup. I guess I'll just do it the old fashioned way.

All that's left for now is the alignment and brake bleed. I went to a car show out at Northstar Motorsports to do something other than work on the car for once and get a few miles on the car and give it a chance to leak.

Installed an auto-blip tonight. Pretty easy to do. Tap into power at the OBD, Clutch top switch, brake light switch, and then 3 throttle wires. When the brake and clutch are depressed at the same time you it'll blip. Duration and and delay are adjustable with the little control box below.

I went to my first track day with the c5 this weekend. I've been to autobahn south enough times that I'm pretty familiar with the line. My previous best in the F82 M4 was 1:38.21. First day out in the new c5 I ran 1:37.94. Down well over 100hp and losing time with shifts vs a DCT. (9c,8r F, 6c,6r R) 30 psi hot F/R

I started out the weekend in Intermediate to make sure I got a coach and since it was the first time on a new platform. I also haven't driven manual in a decade. Figured I'd take it easy. They promoted me to advanced for the second day.

The car has a ton of grip with 315 square. I can definitely feel the lower power though. A lot of cars I'd previously blow by on the straights now had to lift to let me pass in time. The race seats really help. First time using a hans and it makes you really feel locked in there. However this car is making all its time up in corners. It just leaves all the sedan based cars behind there.

1. Burning some oil in the braking zone. The engine is probably under a ton of vaccum and sucking some oil in. Reportedly it clears right up out of the turn, and doesn't impact a high G turn alone. I need to check the oil catch can. Maybe its full?
2. Brake has inconsistent feel. I bled the brake on track. Some people say it is indicative of two things- A leaky master cylinder or air in the ABS. The ABS I need to see if I can get or borrow a tool that can do ABS bleed. I ordered a new master cylinder. Even if it isn't the issue, it is a 25 year old part and probably worth freshening. Probably worth checking the booster vaccum lines too.
3. Check engine light. I ended my day since I couldn't get scanned at the track. Torque pulled O2 low voltage and a bunch of throttle position errors. O2 maybe I melted a harness? I guess we will find out. The TPS errors I suspect are related to the autoblip. I'll contact their support and see what they say. At least nothing major happened.
4. Some oil is leaking. I lost about 1-1.5L a day. Some of it burning, but I have a minor leak when hot. I'll have to chase it down this weekend. Probably just the new oil cooler needs tightened.
5. Grinding noise LR- Either I'm starting to lose a wheel bearing or maybe the axle nut needs torqued. I know SKF trackers are in my future.
6. The tunnel is freaking hot- I think I'll order a c6 tunnel plate and insulation kit and see if that keeps some heat out of the cabin.

Speaking of the new cooler, coolant temps stayed 230-240ish. The oil however was 285 and pretty much never moved. That's kind warm for an oil cooler, isn't it? I was expecting more mid 200's peak.

Poor man's ABS bleed:

• do a standard bleed
• drive car and do a couple stops hard enough to cycle the ABS. Depending on tires, you might have to do this in the rain or "off line" in the marbles somewhere. Big parking lot perhaps, or rainy day.
• do a launch hard enough to engage traction control. Again, marbles or wet pavement may be your friend.
• do another standard bleed

theruleslawyer said:

1. Burning some oil in the braking zone. The engine is probably under a ton of vaccum and sucking some oil in. Reportedly it clears right up out of the turn, and doesn't impact a high G turn alone. I need to check the oil catch can. Maybe its full?
2. Brake has inconsistent feel. I bled the brake on track. Some people say it is indicative of two things- A leaky master cylinder or air in the ABS. The ABS I need to see if I can get or borrow a tool that can do ABS bleed. I ordered a new master cylinder. Even if it isn't the issue, it is a 25 year old part and probably worth freshening. Probably worth checking the booster vaccum lines too.
3. Check engine light. I ended my day since I couldn't get scanned at the track. Torque pulled O2 low voltage and a bunch of throttle position errors. O2 maybe I melted a harness? I guess we will find out. The TPS errors I suspect are related to the autoblip. I'll contact their support and see what they say. At least nothing major happened.
4. Some oil is leaking. I lost about 1-1.5L a day. Some of it burning, but I have a minor leak when hot. I'll have to chase it down this weekend. Probably just the new oil cooler needs tightened.
5. Grinding noise LR- Either I'm starting to lose a wheel bearing or maybe the axle nut needs torqued. I know SKF trackers are in my future.
6. The tunnel is freaking hot- I think I'll order a c6 tunnel plate and insulation kit and see if that keeps some heat out of the cabin.

1. The catch can was pretty full. I also found the hose pretty loose to the TB. I bet it was leaking.
2. Replaced the master cylinder and bleed a ton on the brakes.
3. I took out the the positaps and soldered in the wires instead. o2's look okay.
4. I found the oil block to be leaking. It looks like the temp sensor and a plug. I added some thread sealant, cleaned the surfaces well and reassembled. I was tired and frustrated last time I put it together. Good news is the heat has formed the hoses to their new shape a bit and now it wants to stay in the correct location so getting the screws in is easy.
5. I had a spring in the parking brake loose. not 100% sure it fixed it yet, but I'd bet on the G forces causing the shoe to swing out and rub the inside of the rotor.
6. I added an insulation kit. Its pretty!

I also managed to get 2 more bolts into the headers. I just drilled out the threads completely and used a through bolt. I also finally bought a cordless ratchet. OMG why did I wait so long? Instead of fighting bolts where you get a couple clicks of swing- ziiiiiiip and its out.

In reply to theruleslawyer :

Cordless rachets are great, especially when they can fit into an odd place. 

Track Day #2 is in the books.

It was my first time out with the car at Blackhawk Farms. I had signed up for Intermediate 2 in order to give myself a little more pace buffer while I learned the track in a new car. The track org did something a little different today. They offered transponders for free to hopefully drum up a bit more interested in TT and other timed events. They posted standing throughout the day. I ended up #2 for times at the event. There were two other Corvettes there. A c6z and a c5z. Mid-day the fastest laps list had 10/14 as Corvettes, and 7/14 were me. I'm not going to post any other's people names out of respect for insurance issues with timing, etc. Eventually the c6z put together a lap in the afternoon and beat me by almost 2 seconds. It was kinda funny to watch him on the main straight. I'd enter it fairly close to him and he would be in the brake zone when I was maybe halfway down the straight. I'm not sure what he had done to the car, but it was fast.

Here's the #2 lap

And a passing compilation if you have 25minutes to waste. Unfortunately my camera stopped recording for the most interesting track battle of the day. I probably have it on my Catalyst. The video quality is just ass. I'll post it later if I find it.

• Brakes were much better. I also put the new hawk er-1 pads in this time. Same pedal engagement every time with only the typical ABS activation sink.
• Tunnel temps seemed lower. I didn't measure, but I wasn't baking as much today.
• I'm still consuming oil. About 1qt for the day. Acceptable for all day at redline for a 90k engine.
• The LR wheel is still grinding. I think it really is the bearing. I ordered a set of MPI hubs for the car. Reported they work well in the rear. I might need the more expensive SKF X Trackers for the fronts once they start making noise.
• I think the PS pump is leaking. I was down a minor amount of fluid. I think I saw some drips last time I was under the car. Just a couple ounces had to be put in near the end of the day. Not real surprising as the PS pump is a known weak link in these cars on track.
• I'm getting a CEL for the O2 still. Low voltage in the post-cat O2 on both banks. Seems like there is a laundry list of possible causes. Likely there is still a bit of a leak at the header flange. I could slather them in copper RTV. Its not a problem other than I don't like a CEL popping up on track.

Post track day inspection

• Oil in catch can is probably like 1/2 qt. So I'm not actually burning a ton. No notable leaks up on the lift.
• Installed a new hub in LR. Used a MPI hub which are $250 vs $400 for the skf x trackers. Test drive verified the noise is gone. I have a second for the other rear when it goes.
• PS pump inspection shows there is a leak. I ordered a turn one hp2 unit to replace
• Ordered parts to do the harmonic balancer. It wobbles a little bit. Not critical, but I should take care of it soon.
• Installed new plugs, wires, and boots. The old ones looked badly eroded, but all a nice gray.
• Removed the air system hoses to give me a bit more room to work
• Removed the side air dam. There is a LG motorsport video out there where he talks about them only existing for fuel economy. They create lift. I care more about lift than fuel economy
• Changed the coolant out for distilled water and some water wetter. Hopefully that will bring down my temps a bit.

I also ordered a set of front cooling ducts that turn your fog light holes into much more useful air intakes.

https://www.instagram.com/p/C4wBTMTyUa9/?img_index=1

Last night I finished up the turn one hp2 pump install.

Removal isn't too bad.

1. Remove the accessory belt
2. Remove the alternator (15mm and 13mm for the hot wire)
3. Fully remove the belt
4. Drain the PS fluid
5. Take the lines off the PS reservoir
6. Remove the PS reservoir upward off the bracket. It just snaps in.
7. Use a pry bar to snap the factory PS pulley
8. Unscrew the high pressure line from the pump (16mm)
9. Remove the 4 bolts (13mm) from the pump and remove.
10. Remove the 4 bolts holding the PS bracket to the engine (15mm)

You probably want to replace the high pressure steering line at this point. At a minimum have orings on hand. Its 18mm to remove and you'll never have better access. You might consider replacing the accessory pulley on the bracket. I used a c6 pulley. the turn one pulley works too, but is like 3-4x more

Reassembly is a lot more complex the assembly with the pully going on back on is a lot larger.

1. Remove the throttle body. The tb motor gets in the way. 3 10mm bolts
2. Assemble the pump. You'll need to press the pulley onto the new pump. Its a special tool you can rent from autozone. make sure to transfer the hose.
3. Make sure the high pressure line threads into the new pump. I'd tighten it down all the way a couple times I make sure the threads are clean and formed.
4. put two bolts into the holes on the bracket. The bolt near the pulley is the short one. These two are captive.
5. bolt the pump to the bracket with 4 bolts(13mm). The new pulley allows you to bolt through it
6. slide the assembled bracket and pulley into place
7. Thread the high pressure pump in and tighten(16mm). This is blind and a PITA.
8. put a bolt  loosely into one of the PS reservoir bracket holes to hold the weight of the assembly while you get the 2 captive bolts started.
9. Tighten the two captive bolts (15mm) A stubby wrench really helps, but you only get 1/6 of a turn due to space.
10. remove the bolt from 8.
11. bolt the PS reservoir bracket back one with 2 15mm bolts
12. reassemble the throttle body
13. put the reservoir back in place. Make sure to use the hose clamps
14. bolt the alternator back in place 2x 15mm 1x 13mm
15. Put the belt back on.
16. Fill with PS fluid.
17. Turn the wheels back and forth a few times to cycle the fluid a bit.
18. check PS fluid
19. Turn over the car without spark. (clutch in and throttle 100% will do this) Trying to run the pump a bit without the full speed engine.
20. check fluid
21. Start the engine and turn the wheels back and forth.
22. shut it down and check the fluid. Its probably stabilized now. I'd leave it with the wheels fully to one side. It allows any bubbles to stay trapped on the right side of the PS rack seals.

Good luck. This was a major PITA. FWIW its a good time to do rack work in general as you'll have have really good access to the lines that are super hard to reach when you need to take out the rack. Combo it with a harmonic balancer change.

Back to Autobahn today.

Today was really frustrating.

Session 1 was great. Ran a 1:37.50, but I forgot to put a memory card in my camera. :\ I was running in advanced group and very little interaction with traffic.

Session 2 my car was badly miss firing. I went back to the paddock after 2 laps. After poking around a bit I found the cylinder 7 plug wire managed to pop off. The boot melted inside the plug hole. I got it reattached and the engine seemed okay. A couple rips outside the track to test.

Session 3 I was a couple minutes late and by the time I got to the pits they had black flagged the session. I never found out what happened.

Session 4 I got about 4-5 laps in before the miss fire came back. Then a black flag all which turned into a red flag. First for that for me. Again I never saw the cause. Usually a red flag is pretty serious.  I got back to the paddock and found the 7 wire shorted against one of the headers.

I still had one session, but I gave up early in frustration. I think I got in less than 15 laps all day. I also think I bumped the suspension out of alignment. Not a ton, but the cams are known for slipping on these cars. I have a set of camber lock outs from AMT already. I just need to install them. I finally ran into Phil Jue, who I have been chatting with on various forums for awhile.

Finally the punch list

• Get a new set of plugs and see if it fixes the miss fire. I ordered a set with ceramic boots so hopefully this doesn't happen again.
• Check on the alignment
• Install the fog light air ducts I got
• Do the harmonic balancer. Also got parts for that. Its not critical.

Bummer about the problems both for you and for others!   
 

curious about an earlier statement you made about side skirts being for mileage...   what skirts?? 
 

glad to hear you're enjoying the car though.  I have so much fun with mine on track. 

jfryjfry said:

Bummer about the problems both for you and for others!   
 

curious about an earlier statement you made about side skirts being for mileage...   what skirts?? 
 

glad to hear you're enjoying the car though.  I have so much fun with mine on track. 

I'll let the man himself tell you.

I ordered new set of wires and it cleared up the missfire. The idle stumble went away too. Nice bit is these have ceramic boots that won't melt and have integrated fiberglass insulation to protect them from headers.

https://tonsperformance.com/products/sleeved-9070c?_pos=4&_sid=72c8dc2e0&_ss=r

I also put the 2nd MPI hub on the passenger rear. Not because it was making noise, but having the different design on one side changed the rear enough to feel in the alignment. I figured I might as well even it out since I had the part. Underbody inspection revealed one exhaust manifold lost two nuts at the flange somehow. I also applied RTV to stop a slow seep at the transmission and diff junction. Saturday I'm headed out to an autocross with the car. It'll be interesting to see how I place in the new car since this is the group I won the championship with in the M4.

First real autocross today. NS-2r are not an autocross tire. They take awhile to get enough heat into them to stick. Run 4 before they felt 'okay' and they were barely warm to the touch. The first run was embarassing. The er-1 pads like a bit of heat in them as well. I slide through a cone wall at the end of a straight. In any case I ended up 2nd in class and 6th in raw time for all entrants. The tires did better in the warmer afternoon.

Last night was my first time trials event. I was at Autobahn North, which is normally the configuration reserved for members during the day. However this was an evening event, which was another first. Drivers meeting was 4:45 and first car off about 5:15. Only 3 sessions, but only 3 run groups as well so its a pretty rapid fire event to run, cool down, do stuff to the car and run again.

I ran a 1:11.14 which was good enough for first (1/1) in my class, but 3rd fastest time overall. Not a huge accomplishment, but I was only a few tenths off a c7 GS on slicks. Setup- F 9c 8r R 6c 6r, 30psi target. Other drama was the first session I had like 5 plug wires come loose. Am I doing something wrong here? did I get spark plugs with too small of end balls?

Not a lot of work since the last update. Changed the oil. I installed one AMT motor mount. I got the drivers side in and too a break for the night. I ended up seeing a set of shorty headers on closeout for $200 that will fix my broken stock exhaust manifolds. Cheaper than updating to the 01+ manifold like I was planning on doing. I don't expect to make a ton of power with them, but hoping for 10-15 given I had the older log style headers since its a 99. Anyhow I waited to do the other mount until I do those since I need to drop the headers anyways to access the bolts for the motor mount. Save a little time that way.

Today I finished up with the AMT motor mounts. The stock ones were actually in good condition. The previous owner must have done them at some point. Removing the headers made the job so much easier.

Next up was the $200 hooker shortie headers. They look a lot nicer than the log style 99 headers. I went with new O2 sensors as well since the old ones looked really crusty.

Install wasn't hard. The passenger side they come out the top pretty easy. The driver's side I had to remove the alternator and coil packs to get it in. I had new multi-layer steel gaskets ready to go as well.

Next up was converting to a front breather. You get a set of aluminum ducts and bolt them to the radiator shroud. If you want one- https://www.instagram.com/p/C4wBTMTyUa9/?img_index=1 DM this guy.

After that its mostly a matter of sliding them back in over the radiator. You need to to trim any foam that sticks out below the bumper support for them to fit.

Final product. Its not a lot to look at, but hopefully the extra air will lower my oil temps. Its also prep for a spliter as these cars are bottom breathers and splitters really hamper their cooling ability.

I also need to figure out what to do for a front tow hook. Mine was mounted inside the fog light hole. I could punch a hole in the duct. I think I might try to find a more elegant solution though. Nice to be using the holes for something though. Stock all they do is slow the car. A lot of racers cover them up as its worth a few mph on long straights.

More air never hurt! Nice to see this moving along

Another day, another PB. It was a relatively cool day out at the track starting at 60 in the morning and up to about 80. The first session the previous session had someone drag oil halfway around the track so it was a delayed. Then another break down in my session got it black flagged. I'm a little disappointed I didn't have more time in the cool morning.

I had a few new upgrades. The new motor mounts provided more NVH, but I'm not sure what else. The shorty headers sounded cool, but my vmax didn't really change. I think the car really needs a tune at this point however. The o2 was throwing some errors and the transition to closed to open loop operation was rough. The new ducts were a win. Oil temps were down 15F or so. A much more tolerable high 260's to low 270's. The coolant was down about 20F to around 208F. That's barely what it runs at on the highway. Either way a big win in the cooling dept.

Brakes were acting a little weird. Fine on track where I'm braking with high rpm and closed throttle. Kinda soft at low rpm around the paddock. General googling is pointing at a leak in the booster or the hose to it. Threw a new set of ER1 pads on before the event.

I have a cam ready to go in when I have time. I'm looking to put minimal dollars into the ls1, so I have ls6 springs which are cheap as heck. A "truck" cam Its really designed to max out the cheaper ls6 springs and the cam itself is inexpensive. While its open, a melling 10296 high flow, high pressure oil pump and a harmonic balancer. I'm hoping it'll get me 50hp and keep the low end torque.

The new PB of 1:35.97. That's fairly moving for Autobahn south. If you look at the Savage Geese leader board, that would put about what a f87 M2 or the new Nismo Z does on re71rs with a pro driver.

The best track battle of the day was with a ZL1. He obviously had a lot more power, but I'd reel him in on corners.

Jackie Ding and PhD racing was out there again. I chased the PhD Supra for awhile.

I have another track day coming next weekend. My parents are coming into town and my dad wants to do a ride along with me. He's never been on the track before so I need to make sure to video his reaction.

• Flip my tires on the rim. The outside edge is getting worn. I might get a few more track days out of them.
• Check into the brake booster. I have a few parts on order
• check and make sure I didn't knock loose a hose somewhere with all the work I did on the car last weekend

Last weekend I was out at Blackhawk Farms again, this time with Northwoods shelby club. Two weekends in a row is a lot for me. However my folks came out from Idaho and I took them to the track with me. My dad got to ride on the track for the first time with me. At least they can understand what I'm doing a little better. Unless you've been on a track you can never understand how big the forces are relative to what you're used to on the street.

Anyhow, no time for changes. It was check the car and time for a pad swap. I had killed my front pads. due to some vague shipping dates I ended up with 2 compete sets of er-1 pads trying to get a new set. I guess I'll use them eventually. I moved the rears up to the front to accelerate their wear. I'll find out if ECS stands by their warranty on pads soon. I also did get the tires flipped at crown customs. I hope it gets me through the end of the season on this set.

No new PB's this weekend. However this was my first time out on more than a damp track. It was raining pretty good at the start and tapered off a bit towards the end. Most of the cars packed it up after a couple laps. I stayed out the whole session. You can watch me fumble my way through trying to figure out the wet line.

The only other event of note was me chasing a Rx8 that spun off in front of me. He was back lapping after a short check-in, so no harm done. He definitely had more grip than me. I think he was on Hoosiers. I'd out brake him somehow. Given the spin I have to wonder if he disabled ABS.

Nothing major to track down. The car was relatively hot this weekend, but a slower track and more time at high RPM explains it. The brakes are still pretty inconsistent feeling. They brake fine, but its not a good feeling having your pedal feel change all the time.

I'm pondering going to manual brakes FDF makes a kit that changes the pedal ratio for you. Probably $700 all in. I just looked up using an electric pump off a newer accord- ibooster https://www.evcreate.com/ibooster-donor-vehicles/ There is more development work to do here, but it would give me a boosted pedal that doesn't depending on vacuum, so no variable feel. I think it might actually be cheaper than the manual brakes, but I'd have to figure it out myself rather than have a bolt on setup. The pump is easy. I think I know where I can get a kit to adapt a wilwood MC to the ibooster. I'd need to figure out a bracket to adapt the pump, the linkage to the pedal, and probably redo some brake lines. Wiring looks pretty simple.

Time for a valvetrain upgrade. I'm hoping to raise the rev limit a little bit to avoid the really short trips to 4th gear on some of the local tracks. I'm also prepping for a cam.

• LS6 springs. Super cheap compared to the .660 springs. Should allow 6500rpm easy.
• TSP valve seals- These are the later style seals, but I was getting a puff of smoke on high vacuum with downshifts and this was suggested to fix it. with 90k+ miles its probably time anyways.
• Michigan motorsports trunnions. These will keep the needle bearings from escaping with the higher lift and rpm.
• new gaskets, etc.

I also did a new fuel filter and donut gaskets. Just maintence stuff.

Here's the cam I'm planning on putting in.

https://sdparts.com/i-24138755-sdpc-sdr51902-ls6-power-max-plus-camshaft-upgrade-for-5-7l-6-0l-6-2l.html?srsltid=AfmBOop1srNMz4dWJ71g-Q3AG3JQ2r4OAp0B9wvv6T652nIZgVfh0Aac#!model%3DCORVETTE%7C%7Cmake%3DCHEVROLET%7C%7Cyear%3D1999

I also discovered the drivers side valve cover has been updated to a 2014 unit. There were improvements to the amount of oil the PCV system would suck up over the years.

Another autocross today. No issues with the car. Valve train and new O2 seem to be working out. Oh I didn't mention that in the last update. The cheap no name brand O2 I got off amazon were running terrible. +45% fuel trims. I put new Denso units in while I was doing the valves. Back to -0 to -5% trims.

Anyhow, I ended up 2nd in class. 4th on raw time. Super tight course. I never left 1st gear.