Lessons Learned about Road Racing

[Slow old poop]

I thought you might find these observations interesting. Somebody asked me if I had any tips or insights into prepping a DSM for road races, and this is what I told him:

1. It needs aero: ideally, a splitter and a wing (or maybe just a Gurney flap). It needs to cut through the air on the straights to reach top speed. I could only reach 145 or so at Road America, even with more horsepower than last year. Last year I had an air dam, and hit 143, but we broke it off in the grass a few weeks ago, and didn’t replace it. So, aero helps.

2. The car just doesn’t stick in the corners, even with Hoosiers, so downforce is needed. Maybe my car just sits too high. I could lower it if I flared the fenders, and that might help a lot.

3. Needs better suspension. I run Ground Control with camber plates, but it just doesn’t stick. I don’t know what to recommend for suspension, but there must be something better than Ground Control.

4. Baffle the gas tank. You’ll get fuel starvation in long lefts if you don’t. You can baffle or install a surge tank.

5. Run big brakes. I have Stoptechs, but the standard Stoptechs crack rotors on AWD cars, because of the extra weight. We had to put a 10mm spacer in the calipers so I could run a fatter (1.25 in.) rotor, and that did the trick. Haven’t cracked a rotor all year. Because of the expense in widening the rotor, plus the insane cost of Stoptech rotors ($220 each!), I’d recommend anything but Stoptechs.

6. Replace the ball joints and hubs in the front. These are weak to start with, and will lead to excessive pad knockback, especially with wide tires. I put in residual valves to help stop pad knockback, but I still get it.

7. Put in a custom cage. I have a Kirk bolt in cage, but we had to pay to get it widened because it really doesn’t fit. A good cage builder can fab you a cage for not much more than a bolt in. Make sure the cage is legal for NASA. They can get picky.

8. A really good wheel is the Cobra SVT replica, available at about $100 plus shipping. It’s a 17x9, so it will take 235x17 Toyo Prox tires or 245x17 Hoosiers.

9. Keep a set of rain tires handy. You will clean house if it rains.

10. Watch out for too much heat on the timing belt cover. Install a vent on the hood or shield the cover somehow. It gets really, really hot around the turbo, which melts the cover and takes out your timing belt (been there, done that).

11. When prepping the car this winter, replace every hose, clamp and wire. Invest in a new wiring harness. We have been plagued by electrical problems for two years, thanks to the ancient wiring. Be sure to replace the water hose behind the turbo because it’s a bi*** to fix when it leaks. Check or replace the coil pack (it’s probably shot anyway).

12. In fact, put the car up on jack stands and disassemble, clean and replace everything you can afford to replace. Pull the motor, trans, drivetrain, rear end and go through it all.

13. You can probably get away with installing DSMLink, because nobody can detect it unless they pull the ECU. That will let you tune the car perfectly. Install a wideband O2 so you can tune it properly. Install a Scanmaster so you can see knock. Install a tach with a shift light (boy, does that work good!)

13. Buy yourself a complete set of Helicoils and taps to cover all the bolt sizes on the car, because many of them will be tired iron, and you’ll be Helicoiling like crazy. I have a complete set of Helicoils, but I bought them the hard way—one at a time. Find a source of metric nuts and bolts, and buy a ton of them for use as replacements. Replace the flywheel bolts. Replace the transmission mounting bolts. Replace the intake manifold bolts. LocTite everything. I mean everything! Safety wire helps, too.

If anyone is prepping a car for 2008, I hope this helps. Ignore this advice at your peril.

Rich

 

[underradar92]

1. You may be making more hp, but with the added displacement and the same airflow regulators (cams, >intake especially, done @ 6000 rpm<, turbo, throttle body, etc.) it's all happening at lower rpm. What is your rpm @ 145? It may be at a point where the curve is dropping off already. All the cars I'm familiar with that run 150+ on that track are rocking 100-200 and more, hp than you. The maroon 3000TT (Jesse's car) was only? going 150, and we can only guess what Jack & Aaron are doing. FWIW, I saw 125/130. I wouldn't sweat the numbers.

5. TCE set me up with 1.25 rotors, that's one option on a 1g.

6. Floating rotors go a long way towards solving that one.

10. Agreed. Ducts, shields and vents, are your best friends in road course work.

14. Safety wire is also quite helpful.

I know nothing of the rest of the list, so I cannot comment.

What does your car weigh, race ready?

 

[RusherRacing]

Here are a couple

Replace nuts and bolts with factory replacements. They are actually stronger than Grade 8's.

If you have spare parts bring them to the track they don't do you any good sitting in your shop 4 hours away.

DSM's are heavy so strip that un needed weight, weight reductions is one of the best bangs for the buck

Make sure you have atleast one dedicated friend that you trust to help you wrench because you can't be afraid of wrenching if your racing, and wrenching by yourself sucks. Don't always "trust" the shop to get thing right. Make sure the car is the way you want it before you go flying down a straight at 150mph

If it "could" come loose it will!

Not only vent the front of the car do it correctly. Seal everything except where you want the air to go. Through the brakes intercooler/oilcooler/radiator and out through the hood vent. Run a lower temp thermostat and a higher PSI cap. Also wrap that turbo , manifold and downpipe in some DEI wrap. It will really help your under hood temps.

Drain the overflow tank before every race.

TCE brakes are good, actually I would say the best on the market.

Jon @ TRE really knows his trannies

Have a big bank roll

And most importantly HAVE FUN!

 

[wortdog]

Yeah, Grade 8 bolts should really only be used for putting shelves together or something

Most of the OEM bolts seem to be roughly equivalent to AN bolts, or if you want to do even better there's always NAS bolts and the ARP stuff, many of which you can buy pre-drilled for safety wire.

 

[absolute_DSM]

Last year I had an air dam, and hit 143, but we broke it off in the grass a few weeks ago, and didn't replace it. So, aero helps.

Rich

I told you that day that its road racing, not rally!


Subscribed

 

[talonTSIDriver]

10. Watch out for too much heat on the timing belt cover. Install a vent on the hood or shield the cover somehow. It gets really, really hot around the turbo, which melts the cover and takes out your timing belt (been there, done that).

Holy crap, I have never heard of that before. Good to know!!!

 

[mavisky]

If you can afford it run race gas and run street level boost settings. Not race gas horsepower, but it'll prove to be much more reliable as well as much less susceptible to knock.

 

[D_Eclipse9916]

If you can afford it run race gas and run street level boost settings. Not race gas horsepower, but it'll prove to be much more reliable as well as much less susceptible to knock.

This is definitely what I do, its expensive but its less expensive and time-consuming than a new motor or breaking shit.

The usual things like making sure to torque your wheels with an actual torque wrench, avoid red mist, and that carbontrix vent certainly helps at least get hot air out, not necessarily helpign coolant temps.

Also block off anything in the front that allows air through if its not already being used...

For example I took out my foglights, but there is nothing blocking them so I tape over them every event. This last event, I didnt have time to put in my oil cooler, so I blocked off with loads of tape the opening. This helps the air be forced through radiators and the holes you WANT it to go in. I noticed my temps drop WAAAAYY more dramatically through doing this than a carbon trix vent or when I went to an aluminum radiator.

For Example (oh and yes I did own the gt40) :
http://img139.imageshack.us/img139/4882/18ql9.jpg


Heat shield everything and anything along with ducting, this is another thing I have been working on slowly. IF your in HPDE, dont drag race every straight, I typically just pop it into 5th at 30% on the straights unless I really need to pass someone but usually 30% is enough to pass those slower cars anyway as they slow down for you in HPDEs.


Brakes, COMPRESS those ZONES. You burn up your brakes applying your brakes slowly and then moving into them over longer distances. Be on them as short and hard as possible. This will save your brakes rather than halfway using the brakes all the way down the straight.

Yeah your springs have heavy rates, ya those cool wide tires are cool, but protect em, keep the height up so even at full compression around a corner so you dont scrape your tires. If you look at my pic, you can see thats at full compression and it looks like im lowered....now look at how much ACTUAL leeway I have...

http://img150.imageshack.us/img150/8206/66469015gv3.jpg

BTW For you guys using 1.25, how expensive are those replacement rotors, im running the 13x1.10 inch thick kit right now and I dont seem to have too much of a problem, but once I get into heavy time-trialing who knows.

 

[underradar92]

My Coleman sourced 1.25" thick rotors are around $150.00-ish each.

 

[Evan K.]

Holy crap, I have never heard of that before. Good to know!!!

It looks like this when that happens You can see how far down the upper timing cover sagged. Keep those turbo bolts tight!

http://www.youtube.com/watch?v=l3fhhnU88bA

 

[silver bullit]

Some really good info in here.

 

[talonTSIDriver]

It looks like this when that happens You can see how far down the upper timing cover sagged. Keep those turbo bolts tight!

[video clip above]

Wow, does anyone fab up some sort of aluminium upper timing cover? I am really supprized (and thankful) I have not run into that problem. I do not have any hood vent currently, and have seen coolant temps in the 220-230's before.

Thanks for the warning guys, you may have saved my engine!!!

 

[schemauer]

I'll add some miscellaneous ramblings here as well. Note that some of this will jive with other's posts, while some of it won't. Take it for what it's worth!!

First off I've driven almost every variant of DSM on the track. My first track events were with a bone stock FWD turbo Laser. Then a stock AWD Laser, then a '95 Eclipse that had lot of mods. All of these were also used on the street. I bought the former Archer Racing Talon two years ago to use as my track car. This was a car built by Archer and Chryler Motorsports that ran for one season in '93 and won a championship in a very competitive class. It's 100% race car and not in any way street legal. Also - I like to work on my cars - but what I don't like is bringing an ill-prepared car to the track and laying on my back all weekend under it. For me this gets old very quickly. OK....

I think there also needs to be a determination first off if the car will be track only - or also would need to stay street legal. My best suggestion for anyone would be to first buy a car to use strictly for the track. This will save you lots of headaches right off. If you don't do this do not even toy with the idea of creating a mega-hp street/track car. It's true that anything can be done with enough budget, but this otherwise will be a very frustrating experience. In my opinion a fairly stock, reliable, sorted car is much more fun than one with 500 hp and nothing but breakdowns.

I've now run the Archer car for two summers of open track events. This is the most fun I've ever had at the track. I've not had any issues with the car, nothing has come loose or broken. This car only has ~218 hp at 15psi on race gas. Stock brakes (upgraded pads only), stock body, 16x8 wheels w/245 tires, stock engine (it even had the original head bolts when I took it apart last year) and conservative tune with an old AFC. It runs a simple Eibach/Bilstein coil-over suspension with an adjustable rear sway bar - no front sway bar. FWD. My point is it's a very simple yet lightweight and structurally stiff car. Full cage. And it is very fast. The only "A group" cars it will not run with are the heavily modified, well driven Vettes and such and mega-dollar track monsters. It will lap Road America in about 2:42, which is 3-4 seconds faster than my '95 AWD did with lots more horsepower.

It does not have any hood ducting or brake cooling. Stock radiator and one stock rad fan.

As was mentioned in a previous post, braking technique is critical. Threshold braking for the shortest time possible. 90% of drivers brake WAY too early - most because their big brake kits allow them to!!

The stock engine bay heat shielding is there for a reason.

Preparation is the key. Safety wire everything. Loctite every fastener as it goes back on the car. Use new fasteners of the proper grade. NEVER re-use flywheel bolts, p plate bolts, manifold-to-turbo bolts, etc.... With the exception of one radiator hose, I also do not use any parts-store parts on either the Archer car or my other DSM. Too many times tolerances are incorrect, parts don't fit, or are of poor quality. Cheap parts are cheap parts.

I think the perfect track car would be something like a stripped 1g; full properly constructed cage, coil-over suspension, engine stock at about 14-15 psi on race gas.

 

[mavisky]

Schemauer, I agree as well with your suggestion, and oddly enough that's the exact same setup that won Greg Collier two Super Unlimited Championships in a row. He may not have been breaking track records, but the car was consistent, reliable, and at the time well sorted enough that he could make almost every single race/event and the series points started adding up.

Alot of the parts I'm putting on my car aren't in the name of huge hp, but big reliability.

My motor is internally stock with a smallish 18g turbo running reasonably low boost levels and making no more than 300hp. Stock brakes ( I will be adding ducting for peace of mind), front mount to keep knock away, air to oil cooler, power steering cooler, and upgraded radiator. None of which will make me go faster, but should keep me on the track. Now while these aren't "needed" parts I consider them luxuries of reliability and wouldn't neccesarily say that they aren't needed, but spend accordingly.

Remember in order to finish first, you first must finish.

I will say that I strongly believe that the path I'm taking is the wrong way in one aspect, but the right way in another. Going road racing for the first time with a very capable car can build bad tendencies. Mainly relying on the car to make the lap times and not the driver. My car has abilities that would allow me to still run a decently quick lap time even if I'm not taking the fast line. One thing I think I am doing right is avoiding what I call the Hail Mary buildup. I've seen it many times on the local and national scene. An owner has a little fun in a stock car and begins stockpiling parts for the Hail Mary buildup. At the end of the buildup the car has 20-30 brand new and untested parts on it and any minor issues will have to be weeded out one at a time over the course of multiple events. What's worse is that often these parts are related so you get failure cross-talk meaning that you could have multiple problems in different areas, thereby making it harder to diagnose and repair in a timely manner.

So in re-cap. Start stock, add reliability before performance, and run small autox events if you have to to cheaply test out your new parts. This will maximize your time on track, your reliance on your brain instead of the car, and in the end make both you and your car more competitive.

 

[talonTSIDriver]

Schemauer, I agree as well with your suggestion, and oddly enough that's the exact same setup that won Greg Collier two Super Unlimited Championships in a row. He may not have been breaking track records, but the car was consistent, reliable, and at the time well sorted enough that he could make almost every single race/event and the series points started adding up.

Alot of the parts I'm putting on my car aren't in the name of huge hp, but big reliability.

My motor is internally stock with a smallish 18g turbo running reasonably low boost levels and making no more than 300hp. Stock brakes ( I will be adding ducting for peace of mind), front mount to keep knock away, air to oil cooler, power steering cooler, and upgraded radiator. None of which will make me go faster, but should keep me on the track. Now while these aren't "needed" parts I consider them luxuries of reliability and wouldn't neccesarily say that they aren't needed, but spend accordingly.

Remember in order to finish first, you first must finish.

I will say that I strongly believe that the path I'm taking is the wrong way in one aspect, but the right way in another. Going road racing for the first time with a very capable car can build bad tendencies. Mainly relying on the car to make the lap times and not the driver. My car has abilities that would allow me to still run a decently quick lap time even if I'm not taking the fast line. One thing I think I am doing right is avoiding what I call the Hail Mary buildup. I've seen it many times on the local and national scene. An owner has a little fun in a stock car and begins stockpiling parts for the Hail Mary buildup. At the end of the buildup the car has 20-30 brand new and untested parts on it and any minor issues will have to be weeded out one at a time over the course of multiple events. What's worse is that often these parts are related so you get failure cross-talk meaning that you could have multiple problems in different areas, thereby making it harder to diagnose and repair in a timely manner.

So in re-cap. Start stock, add reliability before performance, and run small autox events if you have to to cheaply test out your new parts. This will maximize your time on track, your reliance on your brain instead of the car, and in the end make both you and your car more competitive.

Very well said. I posted this link once before and I think it deserves a repost:
http://farnorthracing.com/autocross_secrets3.html

Driver will make the biggest difference in lap time than any mod you can do to your car. If you are on a budget, dont spend money on aftermarket suspension and engine mods, just make sure your car is in good running order and spend the money on track time. More track time will make you faster.

 

[turbosax2]

I really appreciate all of you guys sharing your lessons on this thread. This really helps educate noobs like me

 

[eclipsh]

Personally, I'm going the route of replacing old, worn-out parts with upgrades as I go. It is expensive but it beats buying parts twice.

 

[123abc]

Personally, I'm going the route of replacing old, worn-out parts with upgrades as I go. It is expensive but it beats buying parts twice.

That's the way I'm going. FMIC to replace the stock rubber pipes, suspension bushings, shocks, all the little stuff.

Some very good information in this topic, I vote for a sticky.

 

[underradar92]

Personally, I'm going the route of replacing old, worn-out parts with upgrades as I go. It is expensive but it beats buying parts twice.

This is the path I took, it works well, if applied with a focus on reliability over speed. Looking at my mod list doesn't uphold this idea too well, I s'pose.

Luckily I've got very smart friends who were doing track days before I started, so I was able to learn from their struggles.

Anyone looking to do front-mount intercoolers, pay close attention to the airflow around it and thru the radiator.

I actually advocate a street driven (at least a little bit) car, so as to have the ability pre-sort the car before sacrificing an entry fee, at least for a non-competition car. Not sure that's the best route, it works in my case though.

 

[schemauer]

I second the last few posts. Case in point. The Archer car has a pretty stock engine running conservative boost. But it does have an external oil cooler, tranny cooler and a full complement of gauges and warning lights to monitor everything, adjustable brake bias and a big adjustable rear sway bar. It frustrates me a bit to read discussions about how big of a turbo a person should buy for their track car when they probably don't even have the basics covered. Rather spending money on the "next best turbo" it should be spent on redundancy, safety and reliability.

Jim, good point on the front-mounts. I'd seriously consider an upgraded side mount over a front mount for most applications. My '95 GSX had the small Greddy front mount and I did everything I could to keep the water temps down on the track. The Archer car has stock bodywork, no ducting and only one rad fan with a stock radiator. Water and oil temps are never an issue.

 

[underradar92]

I had initially planned on a bigger side mount, but for whatever reason, went with the FM. I was so concerned with coolant temps that I made walls inside the nose plastic so the airflow has to go thru the A/C condensor and radiator, not into the wheelwells. So far I have no cooling issues whatsoever.

I don't even have a fan in the engine compartment, just 2 10" pusher fans between the IC and condensors! Nor do I run the heater.

 

[pagosa dsm]

I second the last few posts. Case in point. The Archer car has a pretty stock engine running conservative boost. But it does have an external oil cooler, tranny cooler and a full complement of gauges and warning lights to monitor everything, adjustable brake bias and a big adjustable rear sway bar. It frustrates me a bit to read discussions about how big of a turbo a person should buy for their track car when they probably don't even have the basics covered. Rather spending money on the "next best turbo" it should be spent on redundancy, safety and reliability.

Jim, good point on the front-mounts. I'd seriously consider an upgraded side mount over a front mount for most applications. My '95 GSX had the small Greddy front mount and I did everything I could to keep the water temps down on the track. The Archer car has stock bodywork, no ducting and only one rad fan with a stock radiator. Water and oil temps are never an issue.

Do you have photos of Acher's suspension?I would like to have a photo of the rear sway bar, and measurements of the bar.You also said it does not have a front bar. Any photos would be appreciated.
Thank you Rick

 

[schemauer]

The front suspension is stock items with the exception of the coil-overs and poly bushings.

The rear sway bar I don't have pictures of, but it is round tubular bar mounted to the back side of the rear supsension crossmember. Probably about a 1/2" OD bar. The mounts look like stock DSM mounts with rubber bushings. On each end of this tube is welded about a 3/4" tube that extends 90 degrees of the sway bar towards the rear of the car about 12". What you might call the swaybar links then attach via a clamp to these two 3/4" pieces, with the upper ends bolted to the frame of the car. The lower ends of the two links, when loose, can slide back and forth on the 3/4" bar, allowing adjustability.

If you really want them I can get pics. I have no idea how to post them here, but I could e-mail them.

 

[schemauer]

OK I lied - I actually got a pic of the front coilover attached.

 

[schemauer]

OK let's try this again. Here is a pic of the front of the car. Tranny cooler on driver's side, oil cooler on passenger side.