3.6L Boxster GT Racer - Page 5 - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Eric523 · 07-17-2015, 10:13 AM

Yep, it has been quite a while... Project has been on the back burner of life, unfortunately. Should be moving into a new home next week, getting married in November... plenty of other things taking up time and budget!

But, there has been some progress! The 4.0L engine is mostly assembled now.

Consists of:
-2005 997 S 3.8L engine case, bored out and sleeved with steel liners for 4.0L displacement
-Custom JE pistons for 4.0L displacement(101mm), reduced valve pocket size for higher compression(13.4:1), bank specific pin offset (allowing for reduction of valve pocket depth), reduced weight by 3D under-cutting (385grams), and reduced friction from race spec piston ring stack
-Carillo rods and Carr bolts
-997 X51 intake manifold
-997 X51 cylinder heads, ported in-house and smoothed over
-Custom HRG dry sump conversion, pump mounted at p/s pump location
-High flow rate spec injectors
-LN classic ceramic IMS bearing
-high grade custom rod bearings
-Custom crankshaft oiling prep

We're now working on the oil tank construction. We've cut open a 2009 GT3 Cup car tank for some investigation and ideas of what we need to do to make ours work.

Next will be some re-wiring on the engine and parts of the car harness for the conversion from the Pectel/Cosworth SQ6 ECU over the Motec M1

Eric523 · 07-17-2015, 10:15 AM

pistons...

Eric523 · 07-17-2015, 10:21 AM

in other news, we've built a "mini me" for a customer in a lower GT class (GT5 in the Porsche Owners Club Cup Racing Series). This car has a 2.5L engine in it, just some light upgrades over a Boxster Spec car...

Eric523 · 07-17-2015, 11:05 AM

wow, looking at the dates on the old posts is depressing. Been too long without the car running

For some more optimistic info, there are other items in the works for the car:

Switching to center-lock wheels. Sold my jongbloeds to a client awhile back and picked up three sets of '09 GT3 cup BBS wheels. Got some new wheel halves made in the correct sizing and will increase the rear size a little bit more to move from 280 width to 300 width slicks.

To go along with the center-lock wheels, I've got a cup car set of air jacks that still need to be installed. Basically just to make servicing the car easier at the track and cut down on some time. Getting a jack under this thing when it is slammed is difficult, even worse when you're in a hurry.

Need to refresh the gearbox. Took it apart for inspection and found some pitting on the 3rd gear. So that will need to be replaced and everything will be freshened up for the increase in power. We'll install some new Guard transmission stub axles and one of their limited slip units. I had been using 993 G50 units before with upgraded discs.

The roof weight has been reduced significantly from our initial prototype. The new lighter version still needs final prep work and paint before installation. Probably going to lose another 25-35lbs over the initial prototype I raced with before and used for our mold.

There will likely be some new aero bits added before we go back out again, those are still TBD. Might wait until we test a bit with the new motor and see where our balance is at.

Eric523 · 07-17-2015, 11:22 AM

for the sake of some more content and reminiscing on when the car was running... found some photos I don't think I shared before.

Eric523 · 07-17-2015, 11:28 AM

https://www.youtube.com/watch?v=yHVExRLQUlg

GTA Time Attack competition at Chuckwalla Valley raceway.

My first day entering the series, we decided to run two days before the event and kind of surprised everyone on the entry. Had an open weekend and wanted to get out in the car. Downside was the time of year (mid-July) and temperature in the desert (well over 100 degrees ambient temps, track was about 170 when they shut it down in fear of tearing up asphalt).

Ended up first overall one day, and second overall the other. We took first in Unlimited RWD class and set the Time Attack track records in both directions that weekend in 2013. As far as I know, they still stand.

Eric523 · 07-17-2015, 11:57 AM

Other than slow progress on the Boxster, I haven't been out of Porsche racing completely. Most of my time at the track has been spent coaching. I have a half dozen racer's I teach about one weekend a month with trackside coaching, data analysis, and spotting on the in car radio systems during qualifying and racing sessions. It sure is a LOT cheaper than racing yourself.... (if anyone is interested in coaching sessions, primarily CA but can travel, PM me)

(coaching office)

I've had some behind the wheel time during data collection, car set-up sessions, teaching new tracks, and co-driving in endurance races. Even got a chance to sneak in a Boxster spec race when a client offered me his car.

Thought I'd share some other photos and videos while I'm here...

Boxster Spec race (data on screen is off). No practice, no qualifying, just hopped in for the race and started at the back. The white car decided to do the same (he finished 1st place in the championship every year since I left).

https://youtu.be/Xo00_mPyPN0

The most exciting car I get to drive... a 2009 GT3 cup converted to GT3R with a 4.0L engine. Photos from Willow Springs at the Tribute to Le Mans 4 hour endurance race. I got to qualify and run about 300 miles, first stint during the day and another stint to finish later in the dark of night. We came in second place by under 2 seconds after 4 hours to the former Dempsey Racing GT3.

Smallblock454 · 07-22-2015, 04:23 AM

Thanks for the video. So all 986 guys now order a 997?

Regards
Markus

jaykay · 07-22-2015, 01:46 PM

Great video, I think I have to give up my 944 ideas and race a Boxster! Always wonder about the run cost differential.

Your passing technique is fearsome!! Stick the nose in from so close so the guy can't even move to defend....love it

That half off pass on the green car was unbelievable...no prisoners! Don't think I will ever be able to pull that