3.6L Boxster GT Racer

[Eric523]

Originally Posted by jaykay

Eric,

Way to kick some cup car butt! Fantastic! Getting past/along side on corner exits....the corkscrew is just incredible!

Did I see some left foot braking in there? For corner balance just before and after the power comes on in certain corners? Does it help you get some more oversteer?

Will "they" let you vent the rear window?

Thanks! I'm sure they don't enjoy getting passed by a hairdressers car with a street M96 motor in it

Yes, I left foot brake every corner that I don't downshift. Actually, even on downshifting corners, I will move my left foot over to the brake pedal to take over braking after downshifting is done. It took me about a year of street driving and practice to really get the feel and coordination down to get it right, but it was well worth it. Now I can modulate equal or better to with my left foot over my right foot.

I do use a left foot tap to get the car to oversteer and control balance as well. If the car is pushing in a corner sometimes a lift off the gas will do it, but a tap of the brake that coincidences with this lift gives an even greater effect. Getting weight transfer off of the rear tires and on to the front can get some more grip up front and allow for a little slide in the rear.

Also, towards the middle of my in car camera at Laguna Seca I was having to pump the brakes with my left foot before entering each braking zone. I was suffering from brake pad "knock-back" with the high G corners and corkscrew. The flex in the caliper and rotor would knock the pads back away from the rotor so the first application of brake would be soft as they returned to the mating surface. Similar to the feel of overheating fluid but a different mechanical issue.

The hard top and rear window were originally built for my Boxster Spec car. At the time, we were not allowed to "vent" the rear window at all. I was also not doing 160+mph anywhere. So that was a big concern after watching the rear view camera at AAA Speedway for the first time. I will have a new roof and window set-up for next year for certain. The wing will also be reinforced.

[Eric523]

Originally Posted by san rensho

Fantastic driving. I noticed in the corkscrew you were spinning up the tires. IS that because the drop is so steep that you get so unweighted that you lose grip? Laguna Seca, car or moto, is definitely on my bucket list.

Thank you. The corkscrew is my favorite corner I have encountered on any track. I do get quite a bit of wheel spin going over the crest due to the lightening of the car. I could probably get out of the gas a bit to reduce this and save tires but it's so darn fun! I quickly regain traction at the bottom under the heavy compression. I tend to shoot out of this corner better than any of my competitors and I have made the race winning pass going into the next set of corners in 5 out of my 6 races at Laguna Seca. They aren't studying my videos well enough... Maybe they will figure it out next year.

[Eric523]

Some changes are in the works for 2013! I'll be coming out with some new items that should improve the lap times by a bit and change the look of the car. I'll share when they are completed

In the meantime, just bought myself another '98 Boxster to drive around on the street! Looking forward to being able to drive one more often now that the race car is so expensive to run.

[jaykay]

Can't wait to see them....maybe you could do a flat underside and diffuser for the rear of the car....would likely save some drag at least

Your flame shot picture is a keeper!

[Eric523]

getting a late start to the season this year mostly due to a heavy workload in the shop. The car will make the 2013 debut April 5-7 at the combined PCA/POC/Pirelli cup Festival of speed event. I've kept most of the progress under wraps from my competition to this point, but once the car gets some fresh paint next week I'll share some more news! If any of you are going to make the event, please stop on by and say hello.

Cage upgrades were on the list. Some of the recent accidents had me thinking more about the speeds this car is reaching now and it doesnt always have to be a mistake to get you in trouble. Added some more 4130 to the cage and also quite a bit of reinforcement to the seat brackets.









Upgraded the ABS system to a four channel TEVES stand alone unit. This is the street car M3 version which is a fraction of the Motorsport unit price. Same pump but the programming is not customizable.



Upgraded to some new 997 cup suspension parts front and rear. Installed some later model subframes that were quite a bit beefier than the '98 versions I was using before. While we were at it, the pick up points were raised a bit.





last but not least, adding some air conditioning!

[Kroggers]

Could you share some more details on the ABS unit you installed - why did you change from the factory Boxster one?

[Eric523]

Well, the unit is made by TEVES, the model is MK60 I beleive. It came installed on factory BMW M3 cars.
The reasons I upgraded the unit are:
- My stock boxster unit was only 3 channel. Which is one channel for each front wheel, and the rears shared a channel. So if one rear tire started to lock, the ABS affected both rears instead of just the one that was locking. Now, with a 4 channel, each wheel can be controlled individually.

- This unit is believed to have better programing for competition than the stock Boxster unit.

- This unit runs with inputs from brake pressure sensors, one for front and one for the rear, as well as a YAW sensor. I can send this brake pressure data into the CAN stream on my dash and log the numbers for driver feedback as well as technical feedback for the brake performance.

- This unit has its own diagnostic that I can plug into. I lost that function in my car for the stock unit when I removed the factory ECU and wiring harness.

I picked the components up from used parts dismantlers and eBay mostly...

[Eric523]

Sunday afternoon project after watching the F1 race today? Carbon dash installation! Quite the task with the new double a-pillar bars on the cage...

[DFW02S]

Wow, nice work!

[insite]

Eric, this is getting out of hand in a hurry. Incredible work; thx for sharing this.

[Eric523]

thanks. it is definitely getting out of hand now.The current version will be very Boxster RSRish. Only thing missing will be the 4.0L motor that is in the works for next year!

[Eric523]

Repainted the interior and exterior of the car. Needed to get the new bars in the cage painted, and the interior was showing some use after two years.

Every panel except the rear quarter panels are new, so they needed paint as well







Changed out the steering column for a later 987/997 version. This later column has an electronic steering angle sensor installed. This will give me more driver feedback data and it was nicer to use a factory part instead of trying to add aftermarket sensors. The column is mounted lower and moved to the right towards the center of the car.

[insite]

so when are you bringing it to road atlanta

[Eric523]

Originally Posted by insite

so when are you bringing it to road atlanta

haha, that would be quite the ride! About 4500 miles round trip from my place. Hopefully it wouldn't end up like the last PCA event there with all of the nice machinery going down on the first lap I would have likely been 2 or 3 rows behind them, right in the thick of the mess!

However, I may make the trip to COTA next year if it is available again. Timing just didn't work out this time around.

[insite]

Yeah, that was quite a spectacle! It WAS pretty wet.....
Announcer was awesome. Pace car in, pack rounding turn 12 "and we are GREEN! GREEN! GREE....oh ****************!!!". Hilarious. One od the gilsdorfs drove his rookie event in that race (his brothers decorated the car w/ tampax livery). He crossed start/finish backward.....and hit the wall. Great weekend despite the weather.


Question about your car. You mention removing the ps pump. Did you go electric, convert the rack, or use a manual rack? How's it drive?

Originally Posted by Eric523

haha, that would be quite the ride! About 4500 miles round trip from my place. Hopefully it wouldn't end up like the last PCA event there with all of the nice machinery going down on the first lap I would have likely been 2 or 3 rows behind them, right in the thick of the mess!

However, I may make the trip to COTA next year if it is available again. Timing just didn't work out this time around.

[Eric523]

Originally Posted by insite

Yeah, that was quite a spectacle! It WAS pretty wet.....
Announcer was awesome. Pace car in, pack rounding turn 12 "and we are GREEN! GREEN! GREE....oh ****************!!!". Hilarious. One od the gilsdorfs drove his rookie event in that race (his brothers decorated the car w/ tampax livery). He crossed start/finish backward.....and hit the wall. Great weekend despite the weather.


Question about your car. You mention removing the ps pump. Did you go electric, convert the rack, or use a manual rack? How's it drive?

Yeah, there are quite a few stories floating around about the debacle.

I removed the stock pump. Installed the electric cup/rsr style unit in the front trunk. It drives great! With the big slicks on the front, the steering still feels very similar to my stock street car. I thought I would hate it, but it gives enough feedback, and the lower effort is nice on the hot three day weekends.

Edit: there is a picture of the elec pump in the front trunk in post #45

[Eric523]

finally got the thing back together for the big Festival of Speed event at AAA Speedway.

New carbon dash, removed 15lbs


new carbon/kevlar seat, new carbon 996 cup doors, new wireless steering wheel that controls Motec display and modes, and a radio button.


new prototype race roof with windows


New 280/650/18 front slicks, went to a wider 10.5'' wheel on the front. Now 18x10.5'' square with 280/680/18 rear and 280/650/18 front.


In the mix with a handful of cup cars and RSR's throughout the weekend.


Best battle was with this 3.9L 400hp 993RSR from Rothsport Racing.


New carbon front fenders, headlight replacement covers, late 996 GT3 bumper and cup splitter


carbon 996 cup doors, cup lexan windows, cup mirrors

[insite]

incredible. did you make that top, or buy it? never seen one like that.

[Homeboy981]

Eric523,

WoW! Now THAT is a serious car! Thanks for even letting me view it here!

Got any driver openings?

Just a thought….but why not go with a dual exhaust straight out the back? It occurs to me, and I'm not a mechanic or a racer car driver. In your exhaust setup at the rear with the bends going back to center, you could shave another 3 lbs. in exhaust tube weight alone. I'm sure you need to 'marry' the pipes to balance it out but could you do that with an "X-tube" type setup closer to the headers or a "bleed" tube of lessor weight and diameter?

Also, would like to see your intake system…IF you happen to have one of those pics.

Were you the only Box represented in the field? Didn't see any other 'side' intakes.

Keep up the good work…and keep us posted! :dance:

[Crono0001]

God. That's not even a boxster anymore. It's like a mid-engine 911 :P