AJ-GT3

This forum has been my go to place for anything GT3 related. The guys here are extremely kind and helpful compared to some other forums (other cars though). I love how you guys don't lecture newbies to "RTFM" and "use the search function" crap. Classy and respectful.

I have owned my car for close to 4 years and it only has 10k miles. I've tracked it multiple times and I love it to bits.

The reason why I decided to join is that I am kind of starting to consider modding the car. Problem is that there is not much data and hard evidence with numbers about what works better so I will have to rely on the collective wisdom of fellow members.

I am looking to improve my times on big tracks mainly. I have MPSC2s already as my first mod and they transformed the car on track. Now I am looking for the next set of mods.

I am an OK driver, I know I can be better with more seat time so I will be co-developing my skills along the way.

I'm looking at this as a complete project from stock. I know that many of you added the mods one at a time but I would like to have some sort of a road map.

1-Headers/exhaust: Dundon makes good long tubes and I believe I have read some good dyno gains. They are quiet expensive though. Cargraphics have some too. What other headers should i consider? any dyno gains table or info?
What about exhaust? Sharkwrks? bbi? cargraphics? its very confusing which system gives the highest HP/TQ gains. Sound needs to be reasonable too as I don't want to **** off cops.

2-Intake: I have read that dyno figures for Fabspeed intake are not representative to real life due to heat entrapment in real life. I have also seen converting to RS intake with a lower profile fan to clear the new intake.

3-Tune: Whats the best solution for tuning the ECU? Cobb? or custom tune? is it needed? safe? i certainly prefer plug and play solutions vs sending the ECU.

4-Shorter final drive: From my research, I believe one of the most important reasons the GT3 is slower than the RS (and 991 GT3) has to do with the final drive ratio. I am thinking about moving to a 32:8 from Carnewal. Anyone running those? Are they easy to swap?

5-Flywheel: lighter flywheel worth it?

6- Wheels and tires: what can be done here?

7-Finally, How can I dial back the understeer? can wider front tires be fitted?

Did I miss anything?

I know that I have come with a zillion questions and i believe some or all of them have been answered somewhere but I am trying to get a holistic advice on a stock car in order to develop a plan.

Thank you in advance for your support.

RennOracle

This might sound out of place, but just get an RS, prices aren't so off and with all you will spend you could get an RS.

Even if you do all of those mods, that will become 15k-25k very fast your gt3 won't still be as good as an RS.

And if you still want to do the mods (LWFW, tire size, shorter final drive aren't needed), you will need headers, LSD (the Gt3 will need too), maybe intake and a tune and it will be even faster.
As for suspension, plenty around, Tractive + DSC right now is the ones to get, or just get someone that actually knows something about suspension (in Porsches mainly) and either do KW (cheap, proven and 'fast') or go with Ohlins (but for the price, better go with tractive).

In economy mode, dundon headers+tune, LSD, KW (I would go with manthey because they can just tell your suspension guy wtf to do regarding alignment, so no one will **** up) and be done with it.

996FLT6

I suggest honing your skills as a driver vs mods to car. At 10k miles - you haven't modded yourself 1st. I get a coach 1st. As far as car goes get a nice track alignment and make sure your lsd hasn't grenaded if stock internals. Mike

Ten Years

Nice car, and nice photo! Just beautiful. I really love these cars in Guards Red. Pretty rare for a 997.2 GT3!

I'm sure the other more experienced members will help you with the other items you've mentioned, but I can offer you my HRE wheels I just took off of my new 997.2 GT3. I do love them very much, but I just don't have the space to store another set of wheels and tires right now, and I'm enjoying running the OEM wheels for now. (Again, the car is brand new to me; it's fun to experience it kind of "factory" first.)

These definitely sit a little more flush than the stock wheels. And the MPSC2 are near new:

https://rennlist.com/forums/parts-ma...b-fitment.html





Anyway, best of luck. Let me know if you have any interest. Thanks.

TheSilverFox

Great advice. Spend $10k on coaching then mod.

That being said love the Dundon headers. Highly recommend

boostedt0y

Nice car...I also have a red 7.2 gt3 I use primarily on track. If you have the mod itch I'd do the following


Pin/weld coolant lines
Side muffler delete to lose ~40lbs off the rear
Guards lsd
Rear toe links
Good brake pads and fluid (I like endless me20 pads and endless fluid)
Good tires (I like nt01 as price isn't bad and very durable)
18 in wheels in 18x9 front and 18x12 rear (I have BBS E07)
Rear roll bar (I have BBi)
Harnesses
Track alignment and corner weight
Cup lip
Bucket seats if you don't have gt2 buckets

After the baseline above, I'd spend money on seat time and maintenance.

You can also add other mods depending on how much you want to spend, but the above setup has treated me well.

On my car I added the cup shifter and cables, fabspeed headers with high flow cats and custom Cobb tune), adjustable front thrust bushings, dsc, bmc drop in filter. I'm running the dual mass flywheel. I'm worried about the cam bolts backing out so I've kept the dual mass flywheel.

If you want to go further than the base mods listed above, I'd add monoballs to remove all rubber in the suspension and coilovers such as mcs, jrz, tractive. If you want to keep going then regear the trans. After that cup aero.

AJ-GT3

As expected... very helpful guys. Truly appreciated.

I will do some more research.

Thanks again.

SwayBar

My suggestion would be to get a dedicated set of track tires and wheels, track brake pads/fluid, and a proper alignment.

A competent driving coach will help drop your lap-times much more than adding hardware to the car.

Mr. Adair

Just to play point counter point the OP said he WANTS to spend money on upgrades. I am sure he knows he can improve more with coaching and track time but let's not forget the joy of proper mods. Let the man spend his money

WheelsB

Welcome to the forums OP.

I can offer you my knowledge on both the exhaust and wheel portions of your quest for a faster vehicle.

In regards to exhaust, you will be hard pressed to find a system that offers a better blend of power gains, sound, weight shedding, durability, and quality than you will find from iPE and Akrapovic's performance exhaust systems.

iPE -

You Tube

Akrapovic -

You Tube

For wheels, you have almost a limitless amount of options. Usually HRE, BBS, and Forgeline are the top options among Porsche owners because of their blend of quality and lightweight construction. My personal favorite, the R101 Lightweight by HRE, is fully custom from the color down to the offset down the the widths. Here's a look at that gorgeous wheel:



Feel free to email me directly at David@WheelsBoutique.com if you'd like to learn more about the exhaust & wheel options. Would love to earn your business and be able to say that I am part of this great project

FruitFly

Lots of great advice here. I am currently mid-mod on my 997.1.

I started with LSD, Cup Wing, Cup Splitter, R7's on BBS, Short Shift, Roll Bar, 5 point harnesses, Sportster Buckets and full clear bra.

I took off the PCCBs and put onsteel rotors. Little sacrifice on threshold breaking, but annual maintenance $'s dropped significantly.

I strongly agree with SwayBar and suggest R7's on dedicated wheels. Huge step up in grip/contact.

The down force the Cup wing provided is also very much a big plus.

Next steps for me are adding the DCS and suspension bits. Then on to exhaust after the center splits. Not going touch the engine though (except for pins & wetter water) as I don't see huge upside and would rather have a second track day car.

As for driving and coaching. I would suggest spending some time in SpecE30 and learning on a momentum car. I did this for a few years and the seat time has been invaluable. There are lots of Arrive and Drive programs out there to rent cars from ($1500-$2500 a weekend for a full race weekend). IMO you will learn faster going slow. Learning to heal toe correctly is better done in a rental car, too.

Please keep us informed as to your progression and choices. Would love to hear what you do/choose.

Jamie@dundonmotorsports

Hi AJ, Welcome.

1-Headers/exhaust: Dundon makes good long tubes and I believe I have read some good dyno gains. They are quiet expensive though. Cargraphics have some too. What other headers should i consider? any dyno gains table or info?
What about exhaust? Sharkwrks? bbi? cargraphics? its very confusing which system gives the highest HP/TQ gains. Sound needs to be reasonable too as I don't want to **** off cops.

We're happy to help! We have a complete package for the 997.2 GT3, Race Headers, Dual Cone Carbon Intake, Plenum and Cobb Tune. On the RS this was good for 40whp gains, on the 997.2 GT3 it's about the same. The important thing here is to get a system that works together. For keeping the sound levels down and the power up, look at one of our Orange Lifetime Center Mufflers, they keep the dB's down! All of our systems are valved so there is no drone at low RPM, or cruising. We have a 30 day if you don't like it send it back, no questions and a lifetime warranty (including tracking).

http://www.dundonmotorsports.com/997...eaders-package
http://www.dundonmotorsports.com/por...n-fiber-airbox
http://www.dundonmotorsports.com/por...center-muffler


2-Intake: I have read that dyno figures for Fabspeed intake are not representative to real life due to heat entrapment in real life. I have also seen converting to RS intake with a lower profile fan to clear the new intake.

See above, can also do just a panel filter (BMC or K&N) to get a few more ponies, but only needed once the exhaust side is opened up.

3-Tune: Whats the best solution for tuning the ECU? Cobb? or custom tune? is it needed? safe? i certainly prefer plug and play solutions vs sending the ECU.

The car adapts pretty well to mods. So if you wanted to do just race headers for example the car will adapt fairly well without a tune. Cobb is a convenient option as you can log with it, and we can revise the tune easily (and free) as you upgrade the car with more mods.



4-Shorter final drive: From my research, I believe one of the most important reasons the GT3 is slower than the RS (and 991 GT3) has to do with the final drive ratio. I am thinking about moving to a 32:8 from Carnewal. Anyone running those? Are they easy to swap?

4.0 LSD is a nice upgrade, needs to be installed by a competent shop as the lash has to be reset.

5-Flywheel: lighter flywheel worth it?

This is one I would caution you on. The 997.2 GT3/RS has a crank harmonic (vibration) that causes the exhaust cam bolts to back out. We sell a harmonic damper for this and recommend it to all. Especially needed if you go to a lighter flywheel

6- Wheels and tires: what can be done here?
18" or 19" are possible to use. CL limit your options a little bit. We're partial to BBS as their quality is one of the best in the business. E07's are a nice option for a cup car look and E88's are a classic 911 option.

http://www.dundonmotorsports.com/por...07-for-991-gt3
(these are available in 18" and to fit the NB 997.2 as well)



jamie at dundonmotorsports.com
18" E07 on 997.2 GT3



7-Finally, How can I dial back the understeer? can wider front tires be fitted?
This is more setup and driving style. Would want to talk about your alignment and sway bar settings. Sometimes it's car, sometimes it's driver over driving the fronts asking for too much out of them. There are some nice easy upgrades for cars with PASM. A DSC suspension tuning box has been very helpful for our drivers, most picking up 1.5-3 seconds in before/after installation. Also tire temps are more even and wear more even side to side.

http://www.dundonmotorsports.com/por...control-module

Give me a ring or email to discuss. I tend to agree that going a bit at a time as you learn the car is a good route. And prioritizing welding the coolant fittings and other maintenance first. That said there are some mods that are best done with the engine/trans out so suitable to do while doing coolant welds and the like (LSD/final drive come to mind).

ngng

is it only a .2 issue? or both .1/.2?

Jamie@dundonmotorsports

mostly a .2 issue, good thing to have on a .1, but not a must have like on a .2

AJ-GT3

Thanks a lot guys.... really helpful.

I appreciate all the experience of actual users who have tested these mods in real life.