911tt

Track Night in America at AMP July 2019.


Greetings fellow Chevrolet Corvette enthusiasts! I just came into possession of a 2003 Z06 in Quicksilver Metallic. According to the Carfax, she’s been gently broken in by 9 previous owners over the course of 84,000 miles. I do suspect that at least a couple of those “owners” were actually dealers, but who am I to question?

She’s a lived well south of the Mason-Dixon and east of the Mississippi her entire life, which I hope means she’s never tasted road salt. She has, however, had a few modifications already, which we’ll get into in a moment.

First, a bit of background: After a series of nimble but modestly-powered imports (RX-8, Evo X, S2000) I found myself in a position to buy a dream car in the form of a 997 generation 911 Turbo. The car is absolutely fantastic, but in hindsight I think I bought an example that’s a little too nice. The result is I feel guilty about putting indiscriminate miles on it and I can’t bear the thought of tracking it for fear of an incident.


A former "daily." Great car, too small for a tall fella.

Obviously I was in need of a beater. A daily driver I could pile miles onto without guilt or shame. Something that I wouldn’t be afraid to park between a lifted F-350 and a slammed Civic at the local Applebee’s. The obvious choice would be some kind of crossover, or maybe a nice little pickup truck. But recently I had an idea. What if my daily driver could live a double life as a track toy?

The practically-minded folks out there are probably poking mental holes in this plan already, but five days into my scheme I am prepared to declare victory.

What could be a better daily than a 16-year-old Corvette? Depreciation is a thing of the past. She’s bullet-proof. And if by some freak anomaly something were to break, parts are cheap and plentiful. I could probably source a replacement engine in less time than it’s taken me to write this post. Not to mention the visceral joy to be found in taming a 405 horsepower beast each and every day.

Wait, did I say 405?

That leads me back to the car. She’s had a bit of work done. As I understand it, she was once owned by the proprietor of a reputable speed shop in the area, and he applied a laundry list of goodies in preparation for using her as his personal road-racing machine. For reasons unknown to me, he never finished the project and I’m told she never made it to the track, aside from an ill-fated drag strip excursion that resulted in a very expensive trans/diff rebuild. A fairy-tale? Maybe, but I like a good story.

Here’s the existing mod list as presented by the previous owner (and verified by me to the extent that I was able):

• "Custom" camshaft kit - unknown specs
• LS2 Throttle Body
• FAST 92mm Intake Manifold
• Halltech Venom Cold Air Intake
• Elite Engineering Catch Can
• Tune (at the shop that installed the upgrades)
• American Racing 1 7/8" Longtube Headers w Catted X-Pipe
• Brey-Krause Harness Bar
• GM T1 Sway Bars with C6 end links
• Bilstein B6 HD Shocks
• RPM Rebuilt Differential with 3.91 Gears
• RPM Rebuilt Transmission
• Monster LT1-S Twin Disc Clutch
• MGW Short Shifter w race ****
• Tick Performance Clutch Speed Bleeder

Claimed 435 HP / 399 LB-FT (dyno-tested at the wheels).

By my calculation that’s easily more than $13K spent on mods, so if you want to look at it that way, the base car cost me less than five grand!

This might be a good time to mention that I’ve never set foot on a track. Technically, I guess that’s not true. I did a brief stint in a 718 Cayman GTS at the Porsche Driving Experience in Atlanta. And I took an RX-8 around a tiny autocross course twice at a Mazda driving event almost fifteen years ago.

Anyway, my plan is this: Get my feet wet with some autocross and HPDE. Figure out what the car needs next. Figure out what kind of driving floats my boat. Take on projects. Have fun. Rinse, repeat.

I do have a few additional upgrades already lined up for the next couple of months:

• Seats (Sparco QRT-R)
• Harnesses (Schroth Flexi 2X2 6-Point)
• Wheels (Forgestar F4 18X11 +53 square in piano black)
• Tires (Michelin Pilot Super Sport 295/35/18)
• Helmet / HANS

I’m told my current wheels are fakes, which likely translates to heavy, of dubious construction, and definitely not my style. The tires are 2015 date code Bridgestone RE760s that don’t inspire a great deal of confidence.

Down the road I expect there will be cooling-related upgrades, maybe some braking, maybe some coilovers, but I think my focus needs to be primarily on safely getting my feet wet and just learning to drive the thing effectively.

If any of you grizzled track rats have advice for this wet-behind-the-ears noobie, I’d love to hear it.

Next time I’ll share some initial driving impressions vs. the 911 and go over a few of the minor issues I’ve already experienced. I really love reading build threads of all kinds and I am very excited to have one of my own for a change.


They sense that the pack has a new alpha.


Getting to know her garage-mates, thankfully she did not make a mess on the floor.

Kubs

Congrats on your purchase! I think your direction is good. Focus on safety items (seat, belts, fresh fluids, new tires, brake pads for track use) and get a good alignment. Focus on learning the car and how it handles before making any big changes (ie more power, coil overs, etc.). When replacing the tires get somethin cheap but not super sticky like a Firestone Firehawk Indy 500. The Super Sports are good tires, but come at a price. You're going to be tearing them up a good bit while learning. You're not going to be setting any records your first time out, and using soft tires can actually mask some bad habits which will rear their ugly head as you start to go faster. Having the car slide a little is not a bad thing and will help teach you proper technique and car control. Being smooth is key with all inputs. Steering, throttle, braking, all need to be super smooth and transition from one to the other smooth.

911tt

Thanks! I picked the PSS because I had a set on my Evo X and really enjoyed them. I wanted something great for the street while I look for my first opportunity to get on the track / autocross course. I'm told there's a 7-10 week lead time on the Forgestars though, which means I'm stuck with the old Bridgestones for a while. There are some track night in america events around here in the coming weeks, but I'm not sure if I trust the old tires enough for that.

fleming23

You have lots of good shops around your areas too. Enjoy the car and maybe I'll see it at the track some day.

911tt

Well that didn't take long! I'm signed up for a Track Night in America event at AMP April 3rd.

In other news, my headlight repair kit showed up. I got the rat-a-tat-tat motor noise on the driver's side literally the second time I turned on the headlights. The kit I got has aluminum gears and I figure I'll knock out both sides while I'm at it.

anth115

Great start to the thread; I'm glad you carried that detailed writing style over from S2ki or wherever!

Good suggestions above re: fluids, alignment etc.
For HPDE I highly recommend instructed events like BMWCCA or through PCA (if they still allow non Porsches). After your safety, maintenance/fluids, and alignment preparations, HPDE will by far provide the greatest ROI. Best of luck with the build.

captain awesome

So you're basically right were I was two years ago. The very first thing you're going to want with any car on track is high temp brake fluid. Stock Z06 pads (if you're still running those) can handle track duty for 1-3 days depending on how hard you brake, then they get cooked and aren't even good for the street anymore. So dedicated track pads should be a consideration as well. Any brake pad is fine for Autocross.

If you plan on doing any serious track duty with this car an oil cooler is an absolute must. On an 80° day in Michigan (not even that hot with regards to southern states) my oil temps were pushing 280° and i'd have to back it off and do 1-2 cool down laps before I could push the car again. After an oil cooler, i rarely see oil temps above 250°, even on a 95° day.

everything else will come with skill. as you push the car harder, you will start to notice other things that need to be upgraded. radiator, trans cooler, diff cooler, better rotors, higher temp brake pads, big brake kit, stickier tires, etc...

another thing to note is camshafts. you said it's not stock, but you dont know the specs. I would try to find out if you can. Camshafts over .570 lift really work the valvetrain on track and valve springs need to be replaced annually so you don't grenade your motor. Many track junkies, myself included, will go as far as to replace the stock ls6 valve springs every 2-3 years as a preventative measure.

there's also a TON of info here, if you haven't read it already. https://www.corvetteforum.com/forums...e-learned.html

911tt

Thanks for the input guys.

What's the list of fluids you'd recommend I replace right off the bat? I assume engine oil and brake fluid. I'm told it has royal purple oil / trans / diff fluid, but don't know when, probably within the last couple thousand miles.

That's a great note on valve springs, it wouldn't have occurred to me. Previous owner didn't want to go to the trouble to remove the camshaft to figure out the specs and I can't say I'm inclined to do it either. Is there a way to determine which springs are being used just by looking at them?

I definitely plan to get instruction before I do any driving in real anger. The track night in america stuff sounds like it will be a lot of fun as long as I can keep it well within my limits, which shouldn't be a problem.

Kubs

Here is a list of everything I recommend for C5's

Engine oil for street/track:
https://www.amsoil.com/shop/by-produ...-EA?zo=1934716

Power Steering Fluid:
https://www.amsoil.com/shop/by-produ...-EA?zo=1934716

Transmission:
https://www.amsoil.com/shop/by-produ...-EA?zo=1934716

Differential:
https://www.amsoil.com/shop/by-produ...90/?zo=1934716

Brake Fluid:
https://www.amsoil.com/shop/by-produ...-EA?zo=1934716

AND0

This is a great thread with lots of good info buried in there.
C5 track HDPE lessons

For first time
Good Alignment is critical
New brake fluid and clutch master cyl fluid replace
Watch power steering fluid too. Change to the Good Redline fluid if can.
Consider changing out coolant to mostly water with coolant conditioner and only a minimum of antifreeze. Nothing beats water for heat transfer and heat capacity.
Hard tires are not necessarily a problem, but if overheated they can chunk and break down.

Other than that get some instruction and see what develops.
Beginners usually don't need oil coolers and XP20 brake pads.

wrkdWS6

Nice car and congrats. You will have a lot of fun doing a TNIA event with that car. Lots of good info has already been provided but I do disagree with what's been said about cams with over .570" lift needing annual valve spring replacement if tracked. That is blanket statement. I felt inclined to post so people don't immediately feel paranoid if they read this thread and happen to track their car with cams exceeding .570" lift. The lift is not the issue, it is the aggressiveness of the lobes used. You can have a .625" lift cam that's easier on the valve springs than a .550" lift cam. My C5Z with a .610" lift cam does not eat valve springs despite being tracked and having the **** kicked out of it on a daily basis. Comes down to the aggressiveness of the lobes, if the proper valve spring is being used, proper installation, etc. Always good to check valve spring pressures here and there especially those that have cams with aggressive ramp profiles that literally beat the **** out of the springs by slamming the valves shut or those that race their cars. You can check the spring pressures of each and every spring with the right tool if you wish. I recently bought an old school Harley with unknown aftermarket cams, etc. and it's just been a PITA not knowing exactly what has been done internally over the years. I'm going to tear the motor apart one of these days because the unknown is killing me but my motivation levels are not just there yet. I do agree it would be beneficial to know what cam is in there. As a start, you could pop off a valve cover and post a pic of what you see inside. I and others may be able to ID the springs to some degree, it's not always easy tho and at the end of the day it won't tell us much since it's only one piece of the puzzle but it's a start.

TrackAire

Congrats on the new ride....C5's make great track cars and are fun to drive on the street. Plus your car looks great....very clean. Here is my advice on keeping a very comfortable daily driver that will also kick butt on the track.

I would suggest running two sets of rims and tires, one for the track and one for the street. The number one factor in a smooth comfortable ride for the street is which tire you decide to run. Since you already have a set of rims and getting the Forgestars, you are set. You can now decide which rims to run on the street and get a very streetable tire that works well as a daily driver and even if you see rain. Your track tires can now be more "disposable" in the regards that they can be of a very track oriented design and usually you can buy cheaper tires to burn up on the track. The Firestone Firehawk Indy 500's mentioned before are a very decent track tire that are pretty inexpensive. The better the track tire, the worse it is on a daily driver and vice a versa. If you do 6 to 10 track type events or autocrosses a year, then it is definitely worth having two sets of tires and rims IMO. Trying to run one set of tires for both usually means a pretty big compromise in daily driving comfort and on-track performance.

Don't worry about the reproduction rims....you might be surprised to find they are not that heavy. I've run two different sets of reproduction rims on my track Mustang for four years and the current owner has been running them for the last 3 years....7 years in total with no issues at all. All rims can crack, from OEM to high end "race" rims. Regardless of which rims you decide to track on, after every event it's a good practice to remove the rims from the car, wash them and inspect them for cracks, etc. If you do decide to coat the Z06 reproductions for track use, do not use plasti-dip as this will hide stress cracks until it is too late.

I can tell you this.....I've gone bonkers on my C5 Z06 with full AMT monoball A-Arms, LG Coilovers, LG rear tie rod kit, solid rod end swaybar links, AMT motor mounts, roll bar, etc. If any car should ride rough or harsh, it is mine. People that ride in my car cannot believe how smooth it is on the road with all the modifications I've done to it. Even purposely running over Bot Dots on the highway, the car does not feel any more harsh or rough than the stock set up. Increased noise and drone will often give the impression of a rough ride, etc. So loud exhaust, lack of insulation or stuff making noises can give the illusion that the car is harsh when really it's just loud. I can drive over normal roads and irregularities and not spill my coffee. The key for a decent street ride is the tire design and tire pressure. My street tires are 315/30/18 BFG Rival S square on 18 x 10.5 Speedlines....not exactly the best tire for street comfort but at 28 psi cold tire pressure they are very nice. Don't over inflate your tires on the street or the car will ride like crap regardless of what you've done to it.

I look forward to seeing what other mods you do.

911tt

I've heard good things about Amsoil but I've never ponied up for it. With that said, NOTHING is too good for my new baby and I'm fully prepared to become a fluid snob

911tt

Thanks, that demystifies things for me a little. I obviously have some research to do because I only have a very basic understanding of what a camshaft does, let alone why a particular upgrade behaves differently than a stock one. I know that this car doesn't like to run at low speed below 2K RPM without lugging, but it screams like a scalded ape up to red line.

My hope is that the guy who selected and installed the camshaft did so with road racing and therefore longevity in mind. I will take a picture of whatever lurks beneath the valve cover soon.

911tt

Everything you said makes a lot of sense. The thing is I am more vain than I would like to admit, and I really don't care for the look of the chrome repros, so I'm just looking for excuses to justify replacing them. Hopefully I can get a bit of cash for them here or on craigslist. I think it is very likely that if, after a couple of track outings, I confirm that this is something I want to pursue further, I will go after a set of dedicated track wheels/tires and use the Forgestars as my daily street setup.

I did not know you could run 315s on the stock rears. I like the idea of picking up a set of Speedlines for track purposes but I was thinking a slightly wider wheel was desirable? I haven't don't a lot of reading on that topic so I'm not sure what's generally accepted as the standard approach. I don't have any concern about fitting into a particular class at the moment, especially given all my motor mods, but I suppose that could change.

Speaking of tire pressure, during my test drive I had trouble keeping the rears from spinning, which I assumed was due to hard old tires. I got it home and the previous owner had filled the rears to 38 psi cold. Fronts were at 28. I can tell you it hooks up a lot better without the rear tires being overfilled by 30+%.

911tt

This was supposed to be a post about my headlight fix, but a) I don't have a whole lot to contribute over what's already been said and b) some new **** has come to light man! (watch The Big Lebowski if you don't get this reference).

So let's gloss over the headlight thing.

I was showing the Z06 to my 5-year-old and thought it would be cool to demonstrate the flip-up headlights. I turned them on, they flipped up and came on. I turned them off, and they flipped back down. Then I decided to get fancy and repeat the process. On. Good. Off. Goo... CLACK CLACK CLACK CLACK. The driver's side headlight flipped back down but then the motor continued to run constantly making a horrid racket.

I didn't freak out because I figure with these cars there are probably some known issues that some guy on ebay has a fix kit for and sure enough that was the case. I disconnected the driver's headlight harness, manually cranked it down, and prepared for my first wrenching session on the car.

First of all, this thread was extremely useful. If you run into the same issue I'd say it's a no-brainer as far as DIY fixes go.

I got a double kit from ebay using aluminum gears. Its contents were nearly identical to the one in the guide.



After getting the headlight motor out and cracking it open (which I imagine you could botch pretty badly if you're not careful) I discovered that water had definitely intruded into the assembly.



The thing is, my motor assembly seems to have a vent hole in it, so it's not exactly surprising that water got in. The guide emphasizes how important it is to get a water-tight seal when you glue the cover back on, but I'm not sure why if the design includes a hole. Anyway, I couldn't abide by the rust, so I took a steel brush, some sandpaper, and eventually a dremel wire wheel to the thing.



I spent 15 more minutes on it after this and it looked nearly perfect. I'm pretty sure it's already rusting once more but I don't intend to ever crack the case open again so ignorance is bliss. Plus it's really satisfying to take a rusty part and make it all shiny.

Reassembly was actually much easier and faster than disassembly and I even managed to do it all without dropping any parts into the abyss. I will say that if you tackle this job you should ignore the advice about disconnecting the battery. You already need to unclip the motor harness so there's really no point unless you like resetting your clock for some reason.

Hooked the battery back up, manually adjusted the driver light to be in the down position, turned the lights on, and everything worked perfectly, EXCEPT I saw something pop off and fall into the blackness below the headlight assembly. After searching with a flashlight for about 10 minutes I finally realized it was the headlight adjuster hole plug. Searched another 10 minutes and decided I'd already wasted $9 worth of my life so I ordered a replacement from Amazon.

Job done! I never feel like I fully own a vehicle until something goes wrong and I fix it, so I was feeling very proud of myself.

...

That is until yesterday when I got home from a work lunch and had to park in the driveway since my garage access was blocked. I happened to glance at the garage floor where the Corvette is usually parked and saw some drips of oil. Uh-oh. I had clearly tempted the fates and lost by bragging in my first post.

I didn't have time to look into it last night but when I woke up with indigestion at 3 o'clock this morning it dawned on me that I have not checked/emptied the catch can. Took some tums, went back to sleep, and headed down in my bathrobe when I got up to take a closer look.

The catch can (Elite Engineering EC2, which has a capacity of 11 oz) was full! ****. I should note that the can was really only 2/3-3/4 full when I removed it but it looks like that's effectively full because the filter seems to dip down into the reservoir space. Hopefully I'm wrong.

As you may have noticed, I'm not an expert, but I immediately guessed that this was bad. That guess was partially confirmed when I googled "what happens if you drive with the catch can full?" and the top result was a post on this forum where the basic tone was, "If you're too stupid to check and empty your catch can on a regular basis you really shouldn't have one in the first place." I can't say I disagree with that sentiment and reading the thread filled me with an odd combination of shame and dread.

I really have no idea how full the can was when I got the car. I've probably run 1.5 tanks of gas through it in the last week (I'll need to check the mileage) and there have been quite a few WOT pulls in 2nd and 3rd. Maybe some 4th. I definitely haven't gone much over 100. Anyway.

I figure the possible scenarios are:
1) Can was already full or nearly full when I got the car and the previous owner wasn't diligent enough about emptying it
2) Can was low or empty when I got it and I've managed to fill it over the course of a couple hundred aggressive miles
3) I'm not experienced enough to correctly guess the actual likely scenario

I'll note the mileage, drive it some more, and check the can level. From what I understand I really shouldn't be filling it very quickly during street driving and if I am I have a big problem.

If anybody has advice on this front I'd love to hear it.


Since I was already in my bathrobe I figured it would be a good opportunity to roll around on the cold concrete floor with a flashlight and my iphone to see if I could figure out where the oil drips on my floor came from. That effort was fruitless (although entertaining for my wife), but then I discovered I could see oily surfaces from above.

Here's the picture I took:


I think what we're seeing is the top of the front leaf spring completely covered in oily sludge. Below that you can see drips on the concrete. Using the old "touch it with your finger" method, I deduced that it's close to a quarter inch of dirt held together by a generous amount of motor oil. If my tastebuds are correct, it is indeed Royal Purple (which tastes like grape). I'm going to build some ramps today so I can get my jack under it and get this thing off the ground. Hopefully I can confirm a drip or seepage coming from somewhere specific, but I also saw that the end of the steering column was coated in the same sludge.

So there may be some exciting new adventures in my future. I'll keep you posted. As always, input, insight, and (constructive) insults are equally appreciated.

acroy

Welcome, thanks for the write-up, and congratulations on the purchase. I am biased, having a Machine Silver Z myself! My background was similar: Several RX7s, an RX8 etc. I tried to love the S2K but couldn't. I very nearly bought a Rossion Q1 but backed out at the last minute when I came to the realization I would be too scared to ever drive it.... thus the Vette, which is fun to drive, fun cheap & easy to work on (relatively), and I don't mind actually using it.

You have a ton of good info above already. My comments:

- of everything you mention, I'd beware the valvetrain! Due to that largish unknown cam. Inability to drive smoothly under 2k, plus the power level, suggests to me it's a pretty big cam (and may not be tuned well). I suggest considering spec'ing your own cam/valvetrain based on your planned use. The cost is moderate, the amount of work is a chore, but then you will have peace of mind.

- Oil leaks: good luck. Usually these are a hassle but not a disaster

- Oil in the catch can: suggest doing a leakdown test, verify the vacuum the engine is pulling, and verify the PCV setup. I recently had a PCV adventure of my own.

- track wheel/tire setup: lots of options there. A known good solution is to run 'square' with 4 OE rear wheels. This allows the tires to be rotated, and when combined with appropriate alignment, really balances the car. There are some interesting track-worthy semi-off-brand tires out there (Maxxis, Federal, etc). A lot of people immediately go to the stickiest tire they can; but as the wise man says sticky tires just 'allow you to make mistakes faster'. A relatively long-wearing, slightly less sticky tire will reduce cost, and may have more progressive (gentler, predictable) break-away behavior. Reduces stress on suspension & wheel bearings, g-forces are a bit lower so less likely to have oil starvation issues, etc. Sticky tires are 'faster' but I actually had more FUN on the track on 200TW Star Specs than on slicks.

- continuing on this topic: TrackAire has more experience than I and a lot of good advice! one take-away: Tires sizes are NOT consistent. The '315' BFG tread width is 11.7". The '295' Toyo T1 is 11.6"... It is worth doing the research on this, as the variability is w-i-d-e. The rear wheel well is 11.5" deep, anything more than that will poke.

good luck!!

Matt_27

Based on the oil on the leaf spring and what I can see around the back of the harmonic balancer, there is a chance it's your front crank seal that is leaking. Mine was doing the same thing. I can also see that your balancer bolt was replaced with an ARP bolt probably when the cam was done, but the balancer is still stock. If the balancer rubber degrades and starts the whole unit wobbling it can lead to higher crank runout and therefore a leaky seal. Replacing the balancer with an ATI unit and installing a new crank seal would be a good idea. Steering rack needs to get moved out of the way to access the balancer. While you're in there it's easy to do the oil pump, timing chain, and camshaft .

wrkdWS6

^^I agree on the ATI balancer. IMO, an ATI 0% or 10% underdriven harmonic balancer and a timing chain dampener (RDE makes one) is a must have for a car that’s tracked. Don’t want to snap a chain or a have wobbly balancer out there, seen it first hand. Good time to port the LS6 oil pump if it hasn’t been. Slippery slope haha.

911tt

Thanks! I'd rather keep the current cam and tune, but as I get more comfortable tearing into this thing I may find myself willing to take on that project. You make a good point on the tires. My entire goal is to have fun (as opposed to being competitive, which may come in time). I'll have an update on that front shortly.

That makes sense. I'll try to verify where the leak is coming from but either way the balancer seems like a smart move.

Slippery slope indeed!

I have more reading to but I feel like I'll be able to get this sorted out on my own without too much trouble. I think I've got a plan formulated for what to do leading up to my TNIA event next week, I'll have a post shortly.

Thanks for the advice guys!