986 Forum - The Community for Porsche Boxster & Cayman Owners

986 Forum - The Community for Porsche Boxster & Cayman Owners (http://986forum.com/forums/)
-   Boxster Racing Forum (http://986forum.com/forums/boxster-racing-forum/)
-   -   3.6L Boxster GT Racer (http://986forum.com/forums/boxster-racing-forum/37148-3-6l-boxster-gt-racer.html)

Eric523 12-05-2012 03:23 PM

Quote:

Originally Posted by jaykay (Post 318738)
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 12-05-2012 03:27 PM

Quote:

Originally Posted by san rensho (Post 318766)
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 12-05-2012 03:30 PM

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:D

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 12-05-2012 04:57 PM

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 03-23-2013 10:40 PM

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.

http://i1089.photobucket.com/albums/...8014574B93.jpg

http://i1089.photobucket.com/albums/...8028E3C7A9.jpg

http://i1089.photobucket.com/albums/...80505FA515.jpg

http://i1089.photobucket.com/albums/...8067ED25B3.jpg

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.

http://i1089.photobucket.com/albums/...7F785BAB5F.jpg

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.

http://i1089.photobucket.com/albums/...7F7138A6DD.jpg

http://i1089.photobucket.com/albums/...7FB767EF0D.jpg

last but not least, adding some air conditioning!

http://i1089.photobucket.com/albums/...7F6403A14E.jpg

http://i1089.photobucket.com/albums/...7F5AF03E2C.jpg

http://i1089.photobucket.com/albums/...7F50ADC7C9.jpg

Kroggers 03-24-2013 08:32 PM

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

Eric523 03-24-2013 08:58 PM

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 03-24-2013 09:21 PM

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...

http://i1089.photobucket.com/albums/...AD781706ED.jpg

http://i1089.photobucket.com/albums/...AD84BA8396.jpg

http://i1089.photobucket.com/albums/...AD7ECBA054.jpg

DFW02S 03-25-2013 10:32 AM

Wow, nice work!

insite 03-26-2013 04:43 PM

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

Eric523 03-31-2013 07:10 AM

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 03-31-2013 07:34 AM

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

http://i1089.photobucket.com/albums/...AC8109F636.jpg

http://i1089.photobucket.com/albums/...AC5DE01CA9.jpg

http://i1089.photobucket.com/albums/...AC45999751.jpg

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.

http://i1089.photobucket.com/albums/...AC2ACE5161.jpg

http://i1089.photobucket.com/albums/...AC31A0288C.jpg

insite 04-01-2013 04:18 AM

so when are you bringing it to road atlanta

Eric523 04-01-2013 02:06 PM

Quote:

Originally Posted by insite (Post 334453)
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 04-01-2013 02:29 PM

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?


Quote:

Originally Posted by Eric523 (Post 334584)
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 04-01-2013 02:36 PM

Quote:

Originally Posted by insite (Post 334589)
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 04-09-2013 11:48 PM

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

New carbon dash, removed 15lbs
http://i1089.photobucket.com/albums/...143D2D3FBC.jpg

new carbon/kevlar seat, new carbon 996 cup doors, new wireless steering wheel that controls Motec display and modes, and a radio button.
http://i1089.photobucket.com/albums/...140A9021E9.jpg

new prototype race roof with windows
http://i1089.photobucket.com/albums/...251F2EF81E.jpg

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.
http://i1089.photobucket.com/albums/...31B166411A.jpg

In the mix with a handful of cup cars and RSR's throughout the weekend.
http://i1089.photobucket.com/albums/...25644930C6.jpg

Best battle was with this 3.9L 400hp 993RSR from Rothsport Racing.
http://i1089.photobucket.com/albums/...25430B9A7F.jpg

New carbon front fenders, headlight replacement covers, late 996 GT3 bumper and cup splitter
http://i1089.photobucket.com/albums/...F3F3991659.jpg

carbon 996 cup doors, cup lexan windows, cup mirrors
http://i1089.photobucket.com/albums/...F17C904D39.jpg

insite 04-10-2013 03:38 AM

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

Homeboy981 04-10-2013 04:15 AM

Eric523,

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

Got any driver openings? :cheers:

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 04-10-2013 04:24 AM

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

Eric523 04-10-2013 06:31 AM

Quote:

Originally Posted by insite (Post 336173)
incredible. did you make that top, or buy it? never seen one like that.

we made it. Made a quick thread on it here : http://986forum.com/forums/boxster-racing-forum/44139-new-boxster-hard-top-prototype.html

Eric523 04-10-2013 06:35 AM

in car video from Festival of Speed : GT Boxster at Festival of Speed on Vimeo

jaykay 04-10-2013 09:52 AM

Sweet video...love the part where you kept momentum and it bouncing off the limiter to try and suprise the rsr out of the chicane section.

Lots to learn from just watching your stuff

Dr.Strangepork 04-22-2013 08:46 PM

Quote:

Originally Posted by Eric523
Been sharing a bit of my GT class Boxster build over the last few months. After a year and a half in the BSR I decided to make a jump to GT class power/weight racing. Considered selling the BSR and trying to get a cup or build a 911 car, but the Boxster platform has been so much fun to drive.

Fantastic thread. What are the rules in GT class? Does the car just have to fall within a certain power to weight range and you can do whatever else you want to it?

Dragonwind 04-24-2013 02:43 AM

Thanks for keeping this updated Eric! I love what you've done.
Chris

Eric523 04-24-2013 07:46 AM

Quote:

Originally Posted by Homeboy981 (Post 336180)
Eric523,

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

Got any driver openings? :cheers:

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:

Thanks! On the exhaust stuff, yes we do like to merge the two sides together. With the suspension subframe and longer 6 speed transmission case, there isn't much room to do any merging further forward in the car. We can't run any pipes underneath because of the low ground clearance either. The pipes I have now are a little longer than absolutely necessary, but that is because we wanted to be able to insert the largest mufflers possible in that straight section in the back leading up to the merge. Every once in awhile we run tracks that have a maximum decibel reading, and the option of adding mufflers there was a goal.

I think there is a few pictures of the intake set-up earlier in the thread. Basically some 3" aluminum pipe running from the throttle body into the rear trunk by the coolant tank. The right side air scoop on the side of the car has been modified to feed air through the right rear quarter panel and into the trunk. A larger cone filter, some sensors, hoses and hose clamps...nothing particularly fancy.

I was the only Boxster that far up front. There was one other 3.4L conversion Boxster there that weekend but it was a few seconds back. There is a Cayman in my class that has some side intakes too but we ran pretty good gap on that car as well.

Eric523 04-24-2013 08:00 AM

Quote:

Originally Posted by Dr.Strangepork (Post 338889)
Fantastic thread. What are the rules in GT class? Does the car just have to fall within a certain power to weight range and you can do whatever else you want to it?

Thanks. Very few rules in the GT class so we can pretty much do what we want.

We have 3 types of tire to choose from: Slicks, DOT <100TW, and DOT>100TW
Cars with slicks must run the most weight, less for <100TW, then even less for >100TW. I've chosen slicks, as does most everyone in the higher classes because the DOT's overheat on the higher HP/higher grip cars. We also have a great contingency program with Yokohama, which is why I have so many of their stickers on my car. Last race weekend, I won a full set of 4 valued at around $2k for my class wins.

Class with Slicks

GT1 less than 7.01 lbs/hp
GT2 7.01-9 lbs/hp
GT3 9.01-11.5 lbs/hp ** I ran 316rwhp and 2850lbs last race (restricted hp and added ballast)
GT4 11.51-14 lbs/hp
GT5 14.01-16.5 lbs/hp
GT6 above 16.5 lbs/hp

Weight is including driver and fuel and you must meet weight at any time during qualifying or the race. We always get weighed in after the race (top 3 finishers).

Only rules are:

-Car are limited to one wing (no front wings attached to the hood). Wings must be single element (no multi element wings). No active or in car adjustable aerodynamic devices.

-All engine swaps must be of the same manufacture.

-all tube frame cars must take the slick weight requirements

-maximum of 350lbs of ballast

-switchable ECU's must be declared, inspected, and explained

Eric523 05-08-2013 09:11 PM

fresh dyno certification runs for the POC event at Buttonwillow this weekend. The boss programmed a drop of about 10 HP to lighten the car 90lbs.

http://i1089.photobucket.com/albums/...04DEC1FC40.jpg

The girlfriend's pink one is coming out to race this weekend too!

http://i1089.photobucket.com/albums/...04F79D8414.jpg

Crono0001 05-08-2013 10:36 PM

Lucky girlfriend :p

Eric523 05-15-2013 08:56 AM

very lucky girlfriend, very fast too!

Eric523 05-15-2013 08:58 AM

Here is a video from qualifying on Tuesday. Was about 3- 4 seconds a lap ahead of second place on Saturday so I decided to run up a class on Sunday. Unrestricted the motor and went for it at +600lbs or down 60rwhp in the GT2 group.

It was pretty darn hot out there, 100°+ ambient temps and 150° track temps, so it was a little slippery...

Buttonwillow GT2 Quali in HRG GT Boxster - YouTube

Eric523 05-15-2013 09:01 AM

http://i1089.photobucket.com/albums/...43BBF04F9B.jpg

http://i1089.photobucket.com/albums/...43C2B565EA.jpg

http://i1089.photobucket.com/albums/...43C7816879.jpg

Eric523 06-05-2013 03:24 PM

some photos from last weekends event taken by Max Flieger.

http://i1089.photobucket.com/albums/...erinterior.jpg

http://i1089.photobucket.com/albums/...terexhaust.jpg

http://i1089.photobucket.com/albums/...rattribute.jpg

Eric523 01-06-2015 03:10 PM

Haven't posted in this thread in what seems like forever.

Lost a motor on the banking of Auto Club Speedway and started planning a new ultimate Boxster engine... It has taken quite some time to get everything together but things are starting to move again.

Bought a 3.8L X51 crate motor. Had a scarred cylinder 3.8L engine sleeved for an increase to 4.0L. Going to use the 4.0L case, worked X-51 heads, X-51 intake, custom 13.4:1 JE Pistons, Carillo rods, GT3 rod bearings, and our new dry sump system. Sold my Pectel ECU and will be making the switch over to the Motec M1 series. There will be a bit or wiring involved in that swap also.

I've finally got the custom pistons in hand from JE. They spent some time scanning the cylinder heads and we clayed the motor to get the valve pockets filled up as much as possible. Their milling process also took out a lot of weight, so we are down to 386 grams.

http://i1089.photobucket.com/albums/...er40Piston.jpg

http://i1089.photobucket.com/albums/...r40piston2.jpg

The dry sump system still has some work left, but it should be pretty trick. More photos when we are further along with assembly. Might be the first one of it's kind on an M97 engine? We may actually end up over 400rwhp and live for awhile...

Also had time to get the custom roof mold done. Selling off the prototype and making some production models now. Hopefully they will offset some of the cost in getting that thing built. The new version is a lot lighter! It is a mix carbon, fiberglass, and foam stiffener.

http://i1089.photobucket.com/albums/...roofproto2.jpg

http://i1089.photobucket.com/albums/...rroofproto.jpg

rastta 01-06-2015 04:15 PM

Damn - that's going to be pretty damn quick unrestricted. Can only imagine what a worked over 4.0L could do in my Boxster.

Eric523 01-06-2015 04:18 PM

Quote:

Originally Posted by rastta (Post 430936)
Damn - that's going to be pretty damn quick unrestricted. Can only imagine what a worked over 4.0L could do in my Boxster.

I don't think anything without a turbo will be running away from me. That's the plan anyway...

Can't wait to find out!

j.fro 01-06-2015 05:46 PM

Droooool!!:p

El Vikingo Tropical 01-07-2015 05:35 AM

whaoooo
 
You are making real killer. ..
I have been reading about your car for some time and it has been an inspiration for me.
So now I'm just to beguine to build my own unit.
I have found a cheap roller chassis from a Cayman to start my little project but with a 3.8L engine.

Tank you!

Regards
Jan

jimk04 01-15-2015 11:43 PM

Eric, I've followed all your posts on here and Renntrack so it's good to see you posting about your Boxster again.

Will be following this closely.

Welcome back!

The Radium King 07-17-2015 09:47 AM

Eric!!! pls tell us about the engine and the dry sump - how's it coming along?


All times are GMT -8. The time now is 03:48 PM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2025, vBulletin Solutions, Inc.
Content Relevant URLs by vBSEO 3.6.0
Copyright 2025 Pelican Parts, LLC - Posts may be archived for display on the Pelican Parts Website