2004 SharkWerks 3.9L 996 GT3 Project: HRE R40 Wheels

Christmas came a little early as last month SharkWerks picked up another shop car project. I've actually been hankering for a 996 GT3 for a while. There's something to be said for the rawness of the car and lack of electronic nannies. It's going to make for a very fun project and we've already mapped things out....

Say hello:


As you can see she's got the European RS tail. No it doesn't really save any weight but what the heck eh?


With GT3 seats going in and a welded-in roll bar from Tony/TCDesign we'll be safe and sound. You can't really see much of the roll bar from here but when the interior comes out I'll shoot some better pictures for you. It's honestly far nicer (not to mention more rigid) than the factory Tequipment set up.

The first order of business was to figure out the exhaust. The stock sound is a little drab compared to a 7GT3. Dropping the side mufflers and throwing on a straight pipe doesn't really give you the best sound IMHO even if it saves weight so that was a non-starter for us. We've always liked the sounds we've made on the 7GT3s with our bypass and our track exhaust. The trouble is that the headers, cats and mufflers on the 6GT3 are completely different from the 7GT3 in terms of design, route and fitment.

So off with that bumper:


Here's the factory headers, cats and mufflers (and heat shields).


Let's get a weight check. 14.1 pounds for the cats (X2):


Then there's the headers coming in at 7.34 pounds (X2):


Then in step the side mufflers weighing in at 23.34 pounds (X2):


That's a total of ~ 90 pounds there on the bum of the car.

I think you can see where I'm going with this... The 30hp power increase from the 6GT3 to 7GT3 can be attributed to a few key areas- higher compression as well as some to the better exhaust/header flow/design and tuning. I'm a big fan of the 997GT3 design as is Porsche Motorsports. Check out the 997 GT3 cup cars and you'll see the very same headers etc... and a cup exhaust not too different from ours. The headers and cats are also combined into one unit and flow a shorter distance saving weight too. So here's what we're putting back on the car in place of that 90 pound stock set up.

The 7GT3 header cat weighs in at 11.28 pounds (X2).


So factor the new headers cats (22.56 pounds) in combination with our Track Exhaust (11 pounds) and we now have a little less junk in our 6's trunk. Total weight = 33.56 pounds and a saving of ~56.44

Installing the 997GT3 header/cat combo... Obviously we're dealing with the same motor (and ports etc...) here so fitment to the engine isn't an issue. The hangers for the stock side mufflers do intrude a bit on the placement of the 02 bungs on the 7GT3 header/cat so we will be removing those as well. If I remember correctly each of those brackets (and there's one on each side) is around 2 pounds for those counting.


You can see the interference in the shot below. Since we're not utilizing the side mufflers we won't be needing those brackets/hangers:


On goes ze SharkWerks Track Exhaust:


Obviously we can't put back the original bumper. But to be honest it's really nothing more than a stock 996 C2 bumper with the same oval cut outs on either side so in comes a rear cup bumper with the center cut out. Notice NO MORE bumperettes...


Before sending it out for paint we did a quick test fit. There are a few things that the cup bumpers don't have that need to be cut... For example the 5mph bumper (which we are still going to use) needs to be modified as does a slit made for the license plate light (we made an LED unit).


The end result should sound similar to this:


There's a LOT more going on with this car and in the coming weeks... but I figure I'd give you this update for now

Here's some pictures of the roll bar by Tony@TC Design...



Out comes the engine...


and we'll be changing that pulley for sure

You can see the intake manifold is quite different to the updated 997 GT3 one (more of a single piece design).



Time to start stripping her down...





Time to play with ze cams!

With the motor undergoing surgery we're left with a few other things to do. Unfortunately when we got the car and inspected the brakes the zircon inserts for the pistons on the caliper were in bad shape and actually broken.... Rebuild time? Maybe... Instead we dusted off our Brembo GTR brake kit (which I've used many times on GT2's, GT3's and TT's). We actually saved some weight with these guys over the factory pieces thanks to the lightweight eight piston calipers and two piece rotors (slotted of course).





With the increase in size we had to test fit the wheels too:




And in the rear:

Ok so in-between the other 3.9 builds we've slowly been making progress on our 996GT3 build.

With the heads off we're down to the pistons now:


The heads...


No thanks to Mooty and JWGT2 she's had a fair amount of usage


Pistons out and removed we're down to the rods (same Titanium ones as in the 997GT3).

A 997GT3 head vs 996GT3 head... almost identical... very minor port difference.


The major difference is the 997GT3 has twin squirters vs single for the 996.

Ok and here we go deeper into the meat and potatoes.... Splitting the case:



Same crank... and GT3-R oil pump (extra pick up) as on the 997GT3...


Same titanium rods...


Before doing any more work we give the case a good bath...



Looking better...



The case now ready for some work



Also sent out the LSD to Gaurd for some work

Back over to assembly now...

In goes the crank, GT3R oil pump, all new bearings and of course the Ti rods....


The EVOMS head stud kit installed:


There was an short break as we moved over to the new shop and James' new engine room. In go the Sharkwerks big bore pistons/liners:



Coming together... and the block starts to grow:




Now we get to the all-important cam shafts:



Timing the cams (these require different timing blocks from from the 997GT3):



More to follow shortly but we're getting closer...

James got the engine is all back in the car:



Dan also installed the SharkWerks FE kit since we're using 996GT3 European buckets:


The cup bumper is now working/fitted with our 997 GT3 Track Exhaust set up as well (yes it's loud!).


Put away for the night after having been run a little for break-in...



A couple of important changes before we take her out on the break-in drive and tuning session:



I have to say she sounds like no other 996GT3 that's for sure. Very 997GT3'ish with some extra mustard.

So we're back home now after a week-long tuning escapade in 115 degree heat (gotta love Arizona in July). I've got to thank Todd, John, Rodd, Ian and the entire staff for being so bloody helpful. In that heat the last thing anyone really wants to do is run the dyno hour after hour and day after day...

Anyways we're taking baby steps here and this first round of tuning we managed to eke out a few ponies. We're up to a peak of 430rwhp but if you look at the graph below showing a bone stock 996GT3 it's at least a good idea of where we're at. We're not revving out to 8800 yet either but Todd feels there's still some headroom left. We've got some room to lean out yet as well so it's possible we'll see an additional 15-20 hp when we return later on this month (or next lol!) for round two. My favorite so far has to be the torque hike from 4300rpms.



Here's the sound of the SharkWerks track exhaust on the 996GT3 revving to 8400rpms.

Here's a behind the scenes look into our experience tuning the 996 GT3. The day James put the final touches on the car, Alex and I made the decision to leave to Arizona (a 12+ hour drive through Los Angeles) around 9 PM. Driving that kind of distance through the desert, in the summer, with a freshly assembled motor would normally be a little unnerving, but we knew with James' attention to detail that we were in good shape.

Todd from EVOMSit sent us a base file (since this was the first 3.9L 996 GT3 and had modified camshafts / race exhaust etc.) and we crossed our fingers as James turned the key - but the car started up beautifully and idled great.



The hours flew by (who doesn't enjoy driving a GT3?) and before we knew it, we were through LA. Nothing stopped us on our trip, but we did find things we did not like about a base tune that would require Todd's fine tuning and dyno time. Nothing beats one-on-one time with Todd for this kind of driveabilty. So en route we made mental notes - a weird low-throttle hesitation here, a flat spot in the power curve there.

In particular, the most noticeable problems with a non-custom tune were at low to mid throttle - sadly where most of a freeway drive is spent. The car would buck a bit when holding speed up hills or gently accelerating (even though it ran decent at wide open throttle). Todd said to keep track of all the imperfections so we could address them one at a time and create a tuned car that ran as good or better than stock. Driving a car like this for 12 hours is a challenge at the least, often frustrating and uncomfortable. We were pretty eager to get out of the car by that point because the fun factor wore off about an hour into the drive.

And soon we were greeted by Arizona sunshine.



When we reached EVOMS headquarters in Scottsdale, we immediately strapped the GT3 down and got to work.



EVOMS has their tools and SharkWerks has ours:


A baseline pull showed a good increase in torque over a stock 996 GT3 and plenty more topend power, but it was clear that Todd could squeeze more out of her. He set up his emulator, so that he could make realtime changes without removing the ECU from the car, and focused on one part of the power curve at a time. Todd logged the changes and constantly watched to see what was happening at different RPMs.

Todd installed two eproms into our ECU as well so that we had a true "dual-mode" if you will. One full map for for 91 octane and one for 93octane that we can switch between (more on this later):



If there was a dent in the power curve (even if it also existed on a stock 996 GT3 as can be seen in the dyno baseline graph below), Todd would make a few changes and run another dyno, and again until he eliminated it.



The dyno did not have a chance to rest for several days nor did James' new 3.9L motor. We must have made 200+ wide open throttle pulls throughout the week in 108F degree heat, each time to squeeze a tiny bit more of out the car or eliminate a potential safety issue. Todd would have us watch the logs while he watched the emulator, and we would tell him "Right now!" when a certain undesired event happened so he could pinpoint the cause.

This video below shows a brief look into the Matrix of Porsche tuning (take the red pill obviously). With the emulator is installed on to our car's ECU and thus we were able to make "on-the-fly" changes and precision tuning.



If you watch this second video below you can also see us doing a dyno run with the emulator hooked up so that we could then see the EVOMSit changes in action to verify what areas of specific maps were being used (cuts out any guesswork). There are obviously certain targets/calls that one wants to achieve but it really does take a lot of time, effort and energy but the end results were worth it.



"Obsessed" is the word I would use to describe Todd's commitment to creating a perfect file and I have never seen such attention to detail from a tuner before. He simply would not let us leave without a perfect running car.

By the end of the trip, the car had picked up an additional 25 HP from its baseline tune file, 30 ft/lb torque, and had a much smoother usable powerband. The biggest noticeable difference vs a stock 6GT3 is in the initial low-end grunt. The change in tq (look at the graphs) almost give it a V8-like response.

When we finally left the Phoenix area late Thursday night, I had the pleasure of driving the first round. As I merged onto the freeway near EVOMS, and "gently" brought the car up to cruising speed, it was obvious that Todd's ~50-hours of tuning were not at all wasted.

The GT3 was so smooth now, incredibly responsive to even the slightest throttle inputs. As smooth as stock? Smoother even perhaps. Look at the dyno and you can see how it looks at wide open throttle, but the real magic was performed in the low load and mid throttle. We were very happy indeed...


It even got slightly better mileage thanks to his light-load level adjustments.


Todd wanted to create a file that is 100% ready, that anyone would be happy with both in a daily driver or a track-only race car. And after a couple trips to Arizona and back I'm confident this 996 GT3 could be driven by anyone.

More videos and pictures will come soon as we dig through all our flipcams and cameras.

HRE R40 Wheels on Project NOPSM

The SharkWerks gang has always been keen on weight savings and not just adding power. Hence, if you're going to change wheels we always think it's fine it they "look nice" but we've always wanted something that's forged, strong and yet lighter than what you're taking off. (Less is more in terms of unsprung weight and rotational inertia for optimal acceleration, handling and braking performance). Designed specifically for track and street applications we've partnered with HRE to outfit our 3.9L 996GT3 project with their new 18 inch R40 one-piece forged (using 6061-T6 forged aluminum) wheels in crazy blue (a la GT3RS in Ze Europe). The R40 is available in 18” diameter and widths ranging from 8.5” – 12” in Multi-lug and Center Lock versions (soon-ish). Note the rattle-gun friendly open dish shape for fast wheel changes! The R40 wheel was derived from and used on race cars that won the 2010 Grand-Am GS Championship.

Let's start off with the factory 996GT3 wheels (also pleasing on the eye) which on the 996GT3 were considered somewhat "light". The stock rears with stock 295/30/18 Michelin Pilot Sport 2 tires mounted are 56.5 pounds:


After the tire is removed the wheel itself comes in at 28.5 (not too shabby):


And over to the fronts with the stock tires mounted (48 pounds):


No doubt these aren't the lightest tire but here's the front wheel with the tire off (25.2 pounds):


Here's the front 18x8.5 HRE wheel weighing in at 18.3 pounds:


And now mounted with the same stock tire (40.5 pounds):


Over to the rear 11 inch wheel coming in at 20.2 pounds:


And with the tire installed it comes in at 47 pounds (check the machining on the inside of the spokes):


What we have here folks is a pretty neat weight cut of 8.3 pounds per corner in the rear and 6.9 pounds per corner in the front. That's a total of 30.4 pounds. It all starts to add up with the 54 pounds taken off of the rear, the light-weight seats, battery, brakes etc... With the wheels themselves being comparable in price to a new set of these factory GT3 wheels lighter is the way we're going

Rear wheels installed:


Front wheels installed. And yes we've got the 8-piston Brembo GTR brake kit to fit with plenty of room to spare. For those of you with PCCB's 18s is not an issue:


On her way home: