DE mods-a consensus?

[SLO-BOB]

nuff said

[Bill Verburg]

My formula for next season is pretty typical I think- R compound rubber, suspension work (I'm thinking JIC), Pole Position driver's seat, harnesses, and some aero aids (ala Jack Olsen design) because my car gets a little squirrely around 130 at RA. I have my ideas, but I'm looking for a majority rules type answer.

Sounds like a good list to me. Wheel/tire and suspension upgrades are the most bang for the buck. Seats, harnesses, rollbar are going to make the experience more enjoyable.

Aero aids are nice but I would put them lower on the list.

[Facey]

seeing as your running a stock c2, i'd kinda think there was some cheap hp to be had , probably in the form of headers and muffler complemented by an intake and re-chip....sometimes this can make a really big differance.

combine that with better rubber and better set-up suspension it could be tons of fun!

[don911]

From my own experience heading down that slippery slope....I see a lot of outflow of cash in your future.

Also, I wouldn't get hung up on lap times. I would set up for max fun and safety....There's no prize money or trophies so who cares if you're 2 seconds faster with R compound tires.

Also, look at the rules in your area if you plan on PCA DEs. Our area has an equal seat rule so anything on the drivers side has to be of equal protection on the pass side.

[Bill Verburg]

Originally posted by don911
From my own experience heading down that slippery slope....I see a lot of outflow of cash in your future.

Also, I wouldn't get hung up on lap times. I would set up for max fun and safety....There's no prize money or trophies so who cares if you're 2 seconds faster with R compound tires.

Also, look at the rules in your area if you plan on PCA DEs. Our area has an equal seat rule so anything on the drivers side has to be of equal protection on the pass side.

I agree 100% w/ these sentiments.

A car that feels like it is on tip toes is no fun(solution- lower, tighter suspension, ROW RS or equivalent is a good goal)
A car that can't hook up is no fun(solution- wheels and tires, lsd, brakes)
A seat that you are sliding out of is no fun.(solution- seats, harnesses, roll bar)

[304065]

Bob,

Here comes the rant again.

The best DE mods are those that enhance safety. In the middle are DE mods that make the car faster and represent a one-time expense. And the worst of all DE mods are those that make the car faster and represent a recurring expense that decrease safety.

Accordingly, if I were in your situation I would sell the C2 and get myself a 914 1.7. Just kidding, but I don't race a 2,2 liter because I'm allergic to big cylinders, I do that because it's more fun to learn to keep your foot off the brakes with 155 HP than it is to put it on them with 255.

So seriously, here's what you should do:

1) HANS device. Not the webbing thing and not that hydraulic shock thing, the original HANS.

2) DAS-sport Rollbar with SFI approved padding for helmet area. Forget the harness bar, all it will do is keep you upright in the seat when the roof caves in. Seat back brace with a minimum 12 square inches to keep the seat back from breaking if you back it in (911's tend to back it in)

3) Recaro SPG HANS version seats for driver and instructor.

4) Schroth five point harnesses for driver and instructor attached to BODY OF CAR with eye bolts.

5) Good data acquisition system. There are many choices, I use the DL90 which is no longer made, but the DL1 is very good, also the G2X or the AIM Mychron. The benefit to learning these facilitate is exponentially better than anything ever before. This will also help you getting on the power earlier and the brakes later, and you can actually see the difference lap-to-lap.

What is NOT on the list:

A) Race tires for a C2 means Fikse FM10's with 245/275 Hoosier R6 or MPSCs. These are like candy, fun for a minute, then gone. In that size, you're probably looking at $1000 per season for a single set and you need a second set of tires to drive to the track. They will improve your lap times by several seconds around that big track, but here's the problem: Hoosiers do NOT squeal before they let go, it's stick stick stick stick SPIN! For DE, you want a treaded street tire at the proper pressure that you can drive to and from the event on, that will give you plenty of squeal before it gives up the ghost.

B) High specific output engine mods. The 2,0 racers use engines that rev to 9,000 rpm that are good for a maintenance rebuild every 20 hours or so. I'm not suggesting you get an RSR 3,8 motor, but a perfectly stock C2 is more than powerful enough to keep up with the competition. Look in the PCA club racing record books for a guy named Oliver Zitzmann-- his C2 has won many, many races even against awesome drivers (and true gentleman racers) like Mike Piera in his 2,7 RS lightweight. Anyway, the point is that the K&N, mass airflow, custom chip route only diminishes engine longevity and delivers not much in terms of payback.

My point is, save your money for the high-dollar consumables when you enter that C2 in E-Stock.

Perhaps not the answer you were looking for, but it's been reinforced by my experience. Good luck, be safe and have fun.

[Formerly Steve Wilkinson]

What I find nice about Toyo RA1s is that they're DOT street-legal, and relatively inexpensive, so I can mount them in the driveway and drive to the track rather than trailering tires and a jack to the track. In fact, some people use them as competition rain tires.

[SLO-BOB]

Originally posted by john_cramer
Accordingly, if I were in your situation I would sell the C2 and get myself a 914 1.7.

That one almost made me blow milk out my nose!

[KTL]

YSafety equipment is certainly very important, and is more critical when deciding what you plan to do with the car. That is, do you plan to use this car to run in an organized race series? If so, you must obviously be sure to do the safety mods in accordance with the appropriate rules. Otherwise you end up doing changes multiple times (start with harness bar, then roll hoop, then more dedicated cage), so do the safety mods right the first time. For example, in PCA-Chicago region, you're limited what run group you can run in by safety equipment (and of course your ability). If you're just out there to have fun and learn the car, then stock safety equipment gets you around well. You can utlilize your stock belt to hold you in the seat a bit better with some tricks. Problem is slippy leather seats stink for zooming around the track.

Just remember that the tire and safety changes (going faster) will bring upon other issues to be dealt with. R compound tires are going to tax your brakes more. So be sure to have appropriate pads and fluid. Don't skimp here. Use race pads like Pagid Yellow, PF97, Porterfield R4 and cooling ducts (ducts may not be necessary to avoid fade, but they'll make your pads, rotors, seals last longer) to save your brakes. And keep in mind that street tires can get you around pretty quickly- just not the ES100.........

I agree with the comment about the tires being able to get you to/from the track. That's one big upside to the street tires. But MPSC, RA-1 and Hankooks have a tread depth that'll get you around on the street for a while. Drawback is that when tread gets shallow you're getting a little risky- your call. And as far as sizes, i'd stick with the 16's (if that's what you've got) to save some $.

IMO the jury is out on suspension mods. Ride height and alignment settings for track use are a must, but stiffer springs, adjustable sway bars, bushings, custom valved shocks, et al. are not urgently necessary. These cars are very capable from the showroom floor (much unlike your Yukon XtraLarge) and are more forgiving with stock suspension equipment. Stiffen it up and you can have a hard time finding the car's limits make it difficult to get the car to drive like you want it to, as well as reduce your lap times.

[SLO-BOB]

Kevin-racing isn't on my radar right now. It's all I can do to find the time for DEs let alone racing. Not to mention I am working a hard on improving the driver even more so than the car. There's a long way to go!

[Formerly Steve Wilkinson]

I have to admit that what scares me a bit is that I drive on the street about 70 percent of the time in a car basically set up for DEs, with a DAS rollbar. Yes, it's padded with approved padding and I have a big, custom-built seatback brace for my Recaro, but I'm terrified of getting rear-ended, since this has become the accident du jour, thanks to makeup-applying, cellphone-using, child-slapping drivers. (My wife was rear-ended in her Boxster at 40 or 50 by some moron in a Ford Excursion who was dealing with the kids in the back seat rather than driving.)

I've even installed LED tail/brake lights and a CHMSL in my '83.

But I suspect that big rollbar is a deficit rather than an asset for a non-helmet-wearing street driver, never mind the padding.

Oh, and tow hooks, by the way, are a very useful asset for DEs. Those towtruck guys don't have time to worry about your perfect front spoiler, or whatever, when all they want to do is jerk you out of the way so the other 149 drivers can continue to have fun. You don't get the option of insisting on a flatbed.

[Grady Clay]

Bob,

Great discussion.

John is right on tack with the safety equipment. I wouldn’t hesitate to include the highest level of protection. This may save your life on the street.

I would add a #6 to his list. That would include making the car more responsive to the driver. One of the most important things you learn at a DE is what your 911 won’t do. It won’t stop on a dime. It won’t go around corners as if on a rail.

How do you learn this – safely? You have the 911 so you can drive at 10/10ths and “save your ass from the alligators.” That is your 911 tells you what it is doing and when you exceed 10/10, you can properly recover with no more than an increase in heart rate and lap time.

Tires that “talk” to you are a good first step but soon you won’t need the audible indicator. You will “feel” the changing grip. Your instructor gave good advice about stiffening. Having your 911 react to your inputs will allow you to “test the waters” around maximum performance and still recover from exceeding it. A softly sprung car can be driven close to equally fast but requires more skill to avoid large inputs. A skilled driver can avoid having to make such corrections. For a learning driver the quicker reaction of the 911 to driver inputs allows for your recovery techniques.

Driving at and around the limit of traction is all about recovery. Michael Shoemacher makes 10 mistakes per lap. His mistakes usually aren’t large and his recovery techniques are almost invisible. Our mistakes are gross and occur hundreds of times per lap. What you are learning is how to recognize the mistake sooner and apply a recovery technique sooner so only your lap time suffers. You don’t ever exit the track backwards.

The down side of a faster reacting 911 is you need to carefully work up to the limit and not assume you can do the correct things first time out. Of course this is true for any car. You don’t want to try and learn with something as fast reacting as a CGT or an RS Spyder. You want some temporal latitude – just not as much as a softly (relative) suspended stock 911.

A 911 is one of the few cars in the world were you have the option of easily adjusting the car’s characteristics to you changing driving skills. John is correct; using a 914 1.7 (or a 924/944) is a good learning option. The same safety and suspension rules apply.


OK, back to your specific questions.

Tires make more difference to a 911 than anything else. As for lap times, you get most “bang for the buck.” I agree, it is (addictive) candy. For your purposes you don’t need the ultimate grip but predictable behavior at the limit of traction and beyond. Recoverability should be the goal. I won’t presume to know the current best tire options.

Stiffer springs, shocks to match and lowering all improve the responsiveness. An oft ignored condition is the 911 should never be on the bump stops. The stiffer springs and sway bars will help that but you want to make sure the combination keeps the suspension compliant. If you ride on a bump stop during cornering, that end of the car suddenly looses traction and bad things happen.

The only engine mods should be toward improved cooling and anything else that will protect the life of the machinery. I greatly favor the “Rubbermaid Solution”
for cheep and effective engine cooling for DE events.

The same is true for the brakes. Remove the dust shields. Add more air through the wheels. Have fresh fluid always. Don’t use the pads past ½. Cool the brakes (and engine) on the cool-off lap.

The seat (and other driver equipment) are the heart of your personal safety, they are also an asset in allowing you to control the 911. The net result is you can simply hold the steering wheel lightly and shift with three fingers. No gorilla grip.

A good set of criteria you might consider are:
Do nothing that can’t be easily undone. Have your “restoration-to-original” parts safely labeled and stashed away.
Use PCA Club Racing safety specs as your basic goal and include HANS and other.
Keep the 911 suitable for the street.

If you find yourself wanting to extend your performance experience, get a fully set-up dedicated race car.

Best,
Grady

[rattlsnak]

Aside from the safety stuff, C2's rock with stiffer suspension, sticky tires, and chip/exhaust. (the car aready has ABS and coilovers,) Thats all you need. You dont need to go buy expensive race wheels, the wheels you have now are easily found for $400.00 a set.

[SLO-BOB]

Originally posted by Grady Clay
One of the most important things you learn at a DE is what your 911 won’t do. It won’t stop on a dime. It won’t go around corners as if on a rail.

How do you learn this – safely? You have the 911 so you can drive at 10/10ths and “save your ass from the alligators.” That is your 911 tells you what it is doing and when you exceed 10/10, you can properly recover with no more than an increase in heart rate and lap time.

Precisely the topic of conversation I was having this a.m. with my wife right after I had to "threshold" brake to avoid some lunkhead who turned left in front of me from the oncoming side. While the 911 won't stop on a dime, it will stop plenty fast. Having spent time learning threshold braking at the last BMWCCA drivers school I was able to grasp the concept of hauling my car down FAST and apply it.

It amazes me how many people that own these cars do not attend driver's schools. I thought I knew my way around my car....until I went to school and found out just how little I did know. I'm still at the bottom of the "going fast" food chain, but I'm learning.

I will also say I LOVE the 911 in all it's forms. It's just a fabulous car. I had BMWs before, which are nice cars in their own right, but the 911 feels like home. In class I laugh to myself as the other students (mostly in M3s) speak of the dreaded "911 oversteer" that will send any hapless victim bass-ackwards off of a turn. I guess it's one of those cars you either love, hate or simply don't understand.

On water cooling-that's inspired. I live in Wisconsin where, unfortunately, high temps are often accompanied by high humidity. Fortunately many events are during cooler weather. None the less, I will consider the "Rubber-Maid" solution.

I truly appreciate the advice-it all makes perfect sense.

[304065]

Bob, you and I have something in common. . . .

1975 2002 Sold
1988 M5 Sold
1991 318iS Sold
1985 325E Sold
1988 3,2 Carrera (218 HP) Sold
1991 3,6 Carrera 2 (247 HP) Sold
1971 2,2 E (155 HP)
1966 2,0 Normal (130 HP)

Guess which one is the most fun to drive? Hint: It starts with 1966

[KTL]

Bob,

Unfortunately I wasn't at Blackhawk last week, but should have been. Instead I attended a tuner-sponsored event at Autobahn CC in Joliet, IL. Quite a fiasco. I would have rather driven the extra four hours to-from Blackhawk to avoid the hassle we experienced. Good learning experience nonetheless though- how NOT to run a DE event. ..........

[SLO-BOB]

Kevin-That's a shame. It was a great time at Blackhawk. There was little shame in getting blown away by Randy Pobst who was the guest of honor. Great weather, fun people, fun track. Hard to ask for more.

A guy I know from Milwaukee area had a blue RSA that I hear lives at Autobahn. I hear it's a nice track-when organized properly.

You have one more chance the weekend of Oct 7th at blackhawk.

[Craig 930 RS]

SLOBOB:

Having about a thousand cutomers, probably about 200 of which drive C2s ...... I've heard a lot of information as to what works in the real world for your car.

My recommendations for car improvements in the near future?

1)ES100s feel squirrely on track, period. Do yourself a big favor and go for RA/1s - game over, no doubt in your noggin'

2) Lowering with corner balance & street/track alignment
Does more for your car feel than any other single *adjustment*

3) Decent brake pads. Of course ;-)
C2 brakes are good, but - now I hear the flames comin' - are juuuuust adequate in a C2 -- ie: RUN WITH FRESH FLUID. Keep the brakes you have.

Go out, have fun. I guarantee you that it will take a few years for you to be up to the level of your car as prepared per the above.